Table of Contents

Filed Pursuant to Rule 424(b)(3)
Registration No. 333-154418

 

Prospectus Supplement to Prospectus dated November 3, 2008

8,500,000 Shares

Common Stock

 

 

We are offering 8,500,000 shares of our common stock. Our common stock is quoted on the Nasdaq Global Select Market under the symbol “COLB.” On August 5, 2009, the last reported closing sale price of our common stock on the Nasdaq Global Select Market was $12.99 per share.

The shares of common stock are not savings accounts, deposits or other obligations of a bank or savings association and are not insured by the Federal Deposit Insurance Corporation or any other governmental agency.

Investing in our common stock involves risks. See “Risk Factors” beginning on page S-8 to read about factors you should consider before buying our common stock.

 

 

Neither the Securities and Exchange Commission nor any state securities regulator has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

 

 

 

		Per Share			Total
Public offering price		$	12.25		$	104,125,000
Underwriting discounts and commissions		$	0.6125		$	5,206,250
Proceeds to Columbia Banking System, Inc. (before expenses)		$	11.6375		$	98,918,750

The underwriters also may purchase up to an additional 1,275,000 shares of our common stock within 30 days of the date of this prospectus supplement to cover over-allotments, if any.

The underwriters expect to deliver the common stock in book-entry form only, through the facilities of The Depository Trust Company, against payment on or about August 11, 2009.

Keefe, Bruyette & Woods

D.A. Davidson & Co.

Prospectus Supplement dated August 5, 2009

---

Table of Contents

ABOUT THIS PROSPECTUS SUPPLEMENT

You should rely only on the information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus. We have not, and Keefe, Bruyette & Woods, Inc., and D.A. Davidson & Co., as underwriters, have not, authorized anyone to provide you with different information. You should assume that the information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed since such dates.

This prospectus supplement is a supplement to the accompanying prospectus that is also a part of this document. This prospectus supplement and the accompanying prospectus are part of a registration statement that we filed with the Securities and Exchange Commission, or the SEC, using a “shelf” registration process. Under the shelf registration statement, we may offer and sell shares of our common stock described in the accompanying prospectus in one or more offerings. In this prospectus supplement, we provide you with specific information about the terms of this offering. Both this prospectus supplement and the accompanying prospectus include important information about us, our common stock and other information you should know before investing in our common stock. This prospectus supplement may also add, update and change information contained in the accompanying prospectus. To the extent that any statement that we make in this prospectus supplement is inconsistent with the statements made in the accompanying prospectus, the statements made in the accompanying prospectus are deemed modified or superseded by the statements made in this prospectus supplement. You should read both this prospectus supplement and the accompanying prospectus as well as additional information described under “Where You Can Find More Information” in the accompanying prospectus before investing in our common stock.

 

S-1

---

Table of Contents

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, including information included or incorporated by reference, may contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements include, but are not limited to, statements about our plans, objectives, expectations and intentions that are not historical facts, and other statements identified by words such as “expects,” “anticipates,” “intends,” “plans,” “believes,” “should,” “projects,” “seeks,” “estimates” or words of similar meaning. These forward-looking statements are based on current beliefs and expectations of management and are inherently subject to significant business, economic and competitive uncertainties and contingencies, many of which are beyond our control. In addition, these forward-looking statements are subject to assumptions with respect to future business strategies and decisions that are subject to change. In addition to the factors set forth in this prospectus supplement, the sections titled “Risk Factors,” “Business” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” from our 2008 Annual Report on Form 10-K and the other documents incorporated by reference in this prospectus supplement, the following factors, among others, could cause actual results to differ materially from the anticipated results:

 

•

local and national economic conditions could be less favorable than expected or could have a more direct and pronounced effect on us than expected and adversely affect our ability to continue internal growth at historical rates and maintain the quality of our earning assets;

 

•

the local housing/real estate market could continue to decline;

 

•

the risks presented by a continued economic recession, which could adversely affect credit quality, collateral values, including real estate collateral, investment values, liquidity and loan originations and loan portfolio delinquency rates;

 

•

interest rate changes could significantly reduce net interest income and negatively affect funding sources;

 

•

projected business increases following strategic expansion or opening of new branches could be lower than expected;

 

•

competition among financial institutions could increase significantly;

 

•

the goodwill we have recorded in connection with acquisitions could become impaired, which may have an adverse impact on our earnings and capital;

 

•

the reputation of the financial services industry could deteriorate, which could adversely affect our ability to access markets for funding and to acquire and retain customers;

 

•

legislation or changes in regulatory requirements could adversely affect the businesses in which we are engaged, our results of operations and financial condition; and

 

•

the efficiencies we expect to receive from investments in personnel, acquisitions and infrastructure could not be realized.

Please take into account that forward-looking statements speak only as of the date of this prospectus supplement or, in the case of any accompanying prospectus or documents incorporated by reference in this prospectus supplement or the prospectus, the date of such document. We do not undertake any obligation to publicly correct or update any forward-looking statement whether as a result of new information, future events or otherwise.

 

S-2

---

Table of Contents

 

S-3

---

Table of Contents

 

S-4

---

Table of Contents

 

S-5

---

Table of Contents

 

S-6

---

Table of Contents

 

S-7

---

Table of Contents

RISK FACTORS

An investment in our common stock involves certain risks. Before you invest in our common stock, you should be aware that there are various risks, including those described below, that could affect the value of your investment in the future. The trading price of our common stock could decline due to any of these risks, and you may lose all or part of your investment. The risk factors described in this section, as well as any cautionary language in this prospectus supplement, provide examples of risks, uncertainties and events that could have a material adverse effect on our business, including our operating results and financial condition. This prospectus supplement also contains forward-looking statements that involve risks and uncertainties. These risks could cause our actual results to differ materially from the expectations that we describe in our forward-looking statements. You should carefully consider the risks described below and the risk factors included in our Annual Report on Form 10-K for the year ended December 31, 2008, as well as the other information included or incorporated by reference in this prospectus supplement and the accompanying prospectus, before making an investment decision.

Risks Associated with Our Business

We cannot accurately predict the effect of the national economic recession on our future results of operations or market price of our stock.

The national economy and the financial services sector in particular are currently facing challenges of a scope unprecedented in recent history. We cannot accurately predict the severity or duration of the current economic recession, which has adversely impacted the markets we serve. Any further deterioration in the economies of the nation as a whole or in our local markets would have an adverse effect, which could be material, on our business, financial condition, results of operations and prospects, and could also cause the market price of our stock to decline. While it is impossible to predict how long these recessionary conditions may exist, the economic downturn could continue to present risks for some time for the industry and our company.

The current economic recession in the market areas we serve may continue to adversely impact our earnings and could increase our credit risk associated with our loan portfolio.

Substantially all of our loans are to businesses and individuals in Washington and Oregon, and a continuing decline in the economies of these market areas could have a material adverse effect on our business, financial condition, results of operations and prospects. A series of large Puget Sound-based businesses have implemented substantial employee layoffs and scaled back plans for future growth. Additionally, acquisitions and consolidations have resulted in substantial employee layoffs, along with a significant increase in office space vacancy in downtown Seattle. Oregon has also seen a similar pattern of large layoffs in major metropolitan areas and a continued decline in housing prices. A further deterioration in the market areas we serve could result in the following consequences, any of which could have an adverse impact, which could be material, on our business, financial condition, results of operations and prospects:

 

•

loan delinquencies may increase further;

 

•

problem assets and foreclosures may increase;

 

•

collateral for loans made may decline further in value, in turn reducing customers’ borrowing power, reducing the value of assets and collateral associated with existing loans;

 

•

securities and loans may become other than temporarily impaired, requiring a write down through earnings to fair value, thereby reducing equity; and

 

•

low cost or non-interest bearing deposits may decrease.

 

S-8

---

Table of Contents

Our loan portfolio mix, which has a concentration of loans secured by real estate, could result in increased credit risk in an economic recession.

Our loan portfolio is concentrated in commercial real estate loans and commercial business loans. These types of loans, as well as real estate construction loans and land development loans, acquisition and development loans related to the for sale housing industry, generally are viewed as having more risk of default than residential real estate loans or certain other types of loans or investments. In fact, the FDIC has issued pronouncements alerting banks of its concern about heavy concentrations of commercial real estate loans. These types of loans also typically are larger than residential real estate loans and other commercial loans. Because our loan portfolio contains a significant number of construction, commercial business and commercial real estate loans with relatively large balances, the deterioration of one or a few of these loans may cause a significant increase in our non-performing loans. An increase in non-performing loans could result in a loss of earnings from these loans, an increase in the provision for loan losses, or an increase in loan charge-offs, which could have an adverse impact on our results of operations and financial condition.

A further downturn in the economies or real estate values in the markets we serve could have a material adverse effect on both borrowers’ ability to repay their loans and the value of the real property securing such loans. Our ability to recover on defaulted loans would then be diminished, and we would be more likely to suffer losses on defaulted loans.

Our Allowance for Loan and Lease Losses (ALLL) may not be adequate to cover future loan losses, which could adversely affect our earnings.

We maintain an ALLL in an amount that we believe is adequate to provide for losses inherent in our portfolio. While we strive to carefully monitor credit quality and to identify loans that may become non-performing, at any time there are loans in the portfolio that could result in losses that have not been identified as non-performing or potential problem loans. We cannot be certain that we will be able to identify deteriorating loans before they become non-performing assets, or that we will be able to limit losses on those loans that have been identified. As a result, future significant increases to the ALLL may be necessary. Additionally, future increases to the ALLL may be required based on changes in the composition of the loans comprising our loan portfolio, deteriorating values in underlying collateral (most of which consists of real estate in the markets we serve) and changes in the financial condition of borrowers, such as may result from changes in economic conditions, or as a result of incorrect assumptions by management in determining the ALLL. Additionally, banking regulators, as an integral part of their supervisory function, periodically review our ALLL. These regulatory agencies may require us to increase the ALLL which could have a negative effect on our financial condition and results of operation.

Nonperforming assets take significant time to resolve and adversely affect our results of operations and financial condition.

Our nonperforming assets adversely affect our net income in various ways. Until economic and market conditions improve, we expect to continue to incur additional losses relating to an increase in nonperforming loans. We do not record interest income on non-accrual loans, thereby adversely affecting our income and increasing loan administration costs. When we receive collateral through foreclosures and similar proceedings, we are required to mark the related loan to the then fair market value of the collateral less estimated selling costs, which may result in a loss. An increase in the level of nonperforming assets also increases our risk profile and may impact the capital levels our regulators believe is appropriate in light of such risks. We utilize various techniques such as loan sales, workouts and restructurings to manage our problem assets. Decreases in the value of these problem assets, the underlying collateral, or in the borrowers’ performance or financial condition, could adversely affect our business, results of operations and financial condition. In addition, the resolution of nonperforming assets requires significant commitments of time from management and staff, which can be detrimental to performance of their other responsibilities. There can be no assurance that we will not experience further increases in nonperforming loans in the future.

 

S-9

---

Table of Contents

Fluctuating interest rates can adversely affect our profitability.

Our profitability is dependent to a large extent upon net interest income, which is the difference (or “spread”) between the interest earned on loans, securities and other interest-earning assets and the interest paid on deposits, borrowings, and other interest-bearing liabilities. Because of the differences in maturities and repricing characteristics of our interest-earning assets and interest-bearing liabilities, changes in interest rates do not produce equivalent changes in interest income earned on interest-earning assets and interest paid on interest-bearing liabilities. Accordingly, fluctuations in interest rates could adversely affect our interest rate spread, and, in turn, our profitability.

The FDIC has increased deposit insurance premiums to restore and maintain the federal deposit insurance fund, which has increased our costs and could adversely affect our business.

The FDIC recently adopted a final rule revising its risk-based assessment system, effective April 1, 2009. The changes to the assessment system involve adjustments to the risk-based calculation of an institution’s unsecured debt, secured liabilities and brokered deposits. The potential increase in FDIC deposit insurance premiums could have a significant impact on Columbia.

On May 22, 2009, the FDIC imposed a special deposit insurance assessment of 5 basis points on each insured institution’s total assets less Tier 1 capital. This emergency assessment will be calculated based on the insured institution’s assets at June 30, 2009, and collected on September 30, 2009. Based on our June 30, 2009 assets subject to the FDIC assessment, the special assessment will amount to approximately $1.4 million. This special assessment is in addition to the regular quarterly risk-based assessment. The FDIC has announced that an additional special assessment in 2009 of up to 5 basis points is probable.

The FDIC deposit insurance fund may suffer additional losses in the future due to bank failures. There can be no assurance that there will not be additional significant deposit insurance premium increases in order to restore the insurance fund’s reserve ratio.

We cannot predict the effect of recently enacted and possible future federal legislation on the U. S. economy and the banking industry; there can be no assurance that these measures will successfully address the current recessionary conditions.

In October 2008, Congress enacted the Emergency Economic Stabilization Act of 2008 (“EESA”), which provided the Treasury with broad authority to implement action intended to help restore stability and liquidity to the U.S. financial markets. Pursuant to the EESA, the Treasury has the ability to purchase or insure up to $700 billion in troubled assets held by financial institutions under the TARP. In October 2008, the Treasury announced it would initially purchase equity stakes in financial institutions under the CPP of up to $350 billion of the $700 billion authorized under the TARP legislation. Columbia is participating in the CPP. The EESA also increased the amount of deposit account insurance from $100,000 to $250,000 effective until December 31, 2013.

In early 2009, the Treasury also announced the Financial Stability Plan which, among other things, provides a new capital program called the Capital Assistance Program, establishing a public-private investment fund for the purchase of troubled assets, and expands the Term Asset-Backed Securities Loan Facility. The Treasury also recently announced plans to create a federal Consumer Financial Protection Agency. This legislation is in the early stages, and it is not possible to predict whether such legislation will be enacted. Due to the recessionary condition of the national economy, it is possible that additional legislation affecting the banking industry may be enacted in the near future. The full effect of legislation recently enacted and broad legislation that may be enacted in the near future on the national economy and financial institutions, particularly on mid-sized institutions like us, cannot now be predicted. There can be no assurance that these measures will successfully address the current recessionary conditions.

 

S-10

---

Table of Contents

A continued tightening of the credit markets and credit market volatility may make it difficult for us to maintain adequate funding for loan growth, which could adversely affect our earnings.

A continued tightening of the credit market and the inability to maintain adequate liquidity to fund continued loan growth may negatively affect our asset growth and, therefore, our earnings capability. In addition to deposit growth and payments of principal and interest received on loans and investment securities, we also rely on borrowing lines with the Federal Home Loan Bank of Seattle (“FHLB”) and the Federal Reserve Bank of San Francisco to fund loans. However, the FHLB has discontinued the repurchase of its stock and discontinued the distribution of dividends. Based on the foregoing, there can be no assurance the FHLB will have sufficient resources to continue to fund our borrowings at their current levels. In the event of a further downturn in the economy, particularly in the housing market, these funding resources could be negatively affected, which could limit the funds available to us making it difficult for us to maintain adequate funding for loan growth. In addition, our customers’ ability to raise capital and refinance maturing obligations could be adversely affected, resulting in a further adverse impact on our business, financial condition and results of operations.

If the goodwill we have recorded in connection with acquisitions becomes impaired, our earnings and capital could be adversely impacted.

Accounting standards require that we account for acquisitions using the purchase method of accounting. Under purchase accounting, if the purchase price of an acquired company exceeds the fair value of its net assets, the excess is carried on the acquirer’s balance sheet as goodwill. In accordance with generally accepted accounting principles, our goodwill is evaluated for impairment on an annual basis or more frequently if events or circumstances indicate that a potential impairment exists. Such evaluation is based on a variety of factors, including the quoted price of our common stock, market prices of common stock of other banking organizations, common stock trading multiples, discounted cash flows, and data from comparable acquisitions. There can be no assurance that future evaluations of goodwill will not result in impairment and ensuing write-downs, which could be material, resulting in an adverse impact on our earnings and capital.

Our ability to access markets for funding and to acquire and retain customers could be adversely affected by the deterioration of other financial institutions or the financial services industry’s reputation.

Reputation risk is the risk to liquidity, earnings and capital arising from negative publicity regarding the financial services industry. The financial services industry continues to be featured in negative headlines about the global credit crisis and the resulting stabilization legislation enacted or proposed to be enacted by the U.S. federal government. These reports can be damaging to the industry’s image and potentially erode consumer confidence in insured financial institutions, such as our banking subsidiary. The deterioration of other financial institutions or the further deterioration of the reputation of the financial services industry could adversely affect our ability to access the markets for funding and to acquire and retain customers.

We may grow through future acquisitions, which could, in some circumstances, adversely affect our profitability measures.

We may engage in selected acquisitions of financial institutions in the future, which may involve the issuance of additional common stock. Any such acquisitions and related issuances of stock may have a dilutive effect on earnings per share and the percentage ownership of current shareholders. There are risks associated with our acquisition strategy that could adversely impact our profitability. These risks include, among others, incorrectly assessing the asset quality of a particular institution being acquired, encountering greater than anticipated costs of incorporating acquired businesses into our company, and being unable to profitably deploy funds acquired in an acquisition. Furthermore, we cannot provide any assurance as to the extent to which we can continue to grow through acquisitions.

 

S-11

---

Table of Contents

Substantial competition in our market areas could adversely affect us.

Commercial banking is a highly competitive business. We compete with other commercial banks, savings and loan associations, credit unions, finance, insurance and other non-depository companies operating in our market areas. We also experience competition, especially for deposits, from internet-based banking institutions, which have grown rapidly in recent years. We are subject to substantial competition for loans and deposits from other financial institutions. Some of our competitors are not subject to the same degree of regulation and restriction as we are. Some of our competitors have greater financial resources than we do. Some of our competitors have severe liquidity issues, which could impact the pricing of deposits in our marketplace. If we are unable to effectively compete in our market areas, our business, results of operations and prospects could be adversely affected.

We operate in a highly regulated environment and may be adversely affected by changes in federal, state and local laws and regulations, including rules and policies applicable to participants in the CPP.

We are subject to extensive regulation, supervision and examination by federal and state banking authorities. Any change in applicable regulations or federal, state or local legislation could have a substantial impact on us and our operations. Additional legislation and regulations that could significantly affect our powers, authority and operations may be enacted or adopted in the future, which could have a material adverse effect on our financial condition and results of operations. The rules and policies applicable to recipients of capital under the CPP have been significantly revised and supplemented since the inception of that program, and continue to evolve. Further, our regulators have significant discretion and authority to prevent or remedy unsafe or unsound practices or violations of laws by financial institutions and holding companies in the performance of their supervisory and enforcement duties. The exercise of regulatory authority generally may have a negative impact, which may be material, on our results of operations and financial condition.

Risks Associated with this Offering and Our Common Stock

The market price of our common stock may decline after the offering.

The price per share at which we sell the common stock may be more or less than the market price of our common stock on the date the offering is consummated. If the purchase price is greater than the market price at the time of sale, purchasers will experience an immediate decline in the market value of the common stock purchased in this offering. If the actual purchase price is less than the market price for the shares of common stock, some purchasers in the offering may be inclined to immediately sell shares of common stock to attempt to realize a profit. Any such sales, depending on the volume and timing, could cause the price of our common stock to decline. Additionally, because stock prices generally fluctuate over time, there is no assurance that purchasers of our common stock in the offering will be able to sell shares after the offering at a price that is equal to or greater than the actual purchase price. Purchasers should consider these possibilities in determining whether to purchase shares in the offering and the timing of any sales of shares of common stock.

Our profitability measures could be adversely affected if we are unable to effectively deploy the capital raised in this offering.

As described below under “Use of Proceeds,” we may use the net proceeds of this offering to fund internal growth, selective acquisitions that meet our disciplined acquisition criteria, or the repurchase of all or a portion of the Series A Preferred Stock issued to the Treasury, and for general corporate purposes. Although we are periodically engaged in discussions with potential acquisition candidates, we are not currently a party to any purchase or merger agreement. There can be no assurance that we will be able to negotiate future acquisitions on terms acceptable to us. Investing the proceeds of this offering in securities until we are able to deploy the proceeds would provide lower margins than we generally earn on loans, potentially adversely impacting shareholder returns, including earnings per share, net interest margin, return on assets and return on equity.

 

S-12

---

Table of Contents

The Series A Preferred Stock diminishes the net income available to our common shareholders and earnings per common share, and the Warrant may be dilutive to holders of our common stock.

The dividends accrued and the accretion on discount on the Series A Preferred Stock reduce the net income available to common shareholders and our earnings per common share. The Series A Preferred Stock is cumulative, which means that any dividends not declared or paid will accumulate and will be payable when the payment of dividends is resumed. The Series A Preferred Stock’s dividend rate will increase to 9% per annum five years after its original issuance if not earlier redeemed. If we are unable to redeem the Series A Preferred Stock prior to the date of this increase, the cost of this capital to us will increase substantially on that date, from 5.0% per annum to 9.0% per annum. Depending on our financial condition at the time, this increase in the annual dividend rate on the Series A Preferred Stock could have a material negative effect on our earnings and could also adversely affect our ability to declare and pay dividends on our common shares. Shares of Series A Preferred Stock will also receive preferential treatment in the event of the liquidation, dissolution or winding up of Columbia. Additionally, the ownership interest of the existing holders of our common stock will be diluted to the extent the Warrant is exercised. The shares of common stock underlying the Warrant represent approximately 4% of the shares of our common stock outstanding as of June 30, 2009 (including the shares issuable upon exercise of the Warrant in our total outstanding shares and not including the 50% reduction in the number of shares subject to the Warrant which we expect would occur if we raise at least $76.9 million in this offering or in this offering and one or more qualified offerings prior to December 31, 2009). Although the Treasury has agreed not to vote any of the shares of common stock acquired upon exercise of the Warrant, a transferee of any portion of the Warrant or of any shares of common stock acquired upon exercise of the Warrant is not bound by this restriction.

Finally, the terms of the Series A Preferred Stock allow the Treasury to impose additional restrictions, including those on dividends and including unilateral amendments required to comply with changes in applicable federal law.

Holders of the Series A Preferred Stock have certain voting rights that may adversely affect our common shareholders, and the holders of the Series A Preferred Stock may have interests different from our common shareholders.

In the event that we fail to pay dividends on the Series A Preferred Stock for an aggregate of at least six quarterly dividend periods (whether or not consecutive), the Treasury will have the right to appoint two directors to our board of directors until all accrued but unpaid dividends have been paid; otherwise, except as required by law, holders of the Series A Preferred Stock have limited voting rights. So long as shares of the Series A Preferred Stock are outstanding, in addition to any other vote or consent of shareholders required by law or our amended and restated articles of incorporation, the vote or consent of holders owning at least 66 ²/3% of the shares of Series A Preferred Stock outstanding is required for:

 

•

any authorization or issuance of shares ranking senior to the Series A Preferred Stock;

 

•

any amendments to the rights of the Series A Preferred Stock so as to adversely affect the rights, preferences, privileges or voting power of the Series A Preferred Stock; or

 

•

consummation of any merger, share exchange or similar transaction unless the shares of Series A Preferred Stock remain outstanding, or if we are not the surviving entity in such transaction, are converted into or exchanged for preference securities of the surviving entity and the shares of Series A Preferred Stock remaining outstanding or such preference securities have the rights, preferences, privileges and voting power of the Series A Preferred Stock.

The holders of Series A Preferred Stock, including the Treasury, may have different interests from the holders of our common stock, and could vote to block the foregoing transactions, even where considered desirable by, or in the best interests of, the holders of our common stock.

 

S-13

---

Table of Contents

We may not be able to continue paying dividends on our common stock at recent levels or at all.

In January 2009, we declared a quarterly cash dividend of $0.04 per share, paid February 25, 2009. In April 2009, we declared a quarterly cash dividend of $0.01 per share, paid May 20, 2009. On July 22, 2009, we declared a quarterly cash dividend of $0.01 per share, payable on August 19, 2009 to shareholders of record on August 5, 2009. The decision to reduce the quarterly cash dividend as compared to recent quarters was based on the board of directors’ review of Columbia’s dividend payout ratio and dividend yield balanced with our desire to retain capital. The payment of cash dividends is subject to Federal regulatory requirements for capital levels and other restrictions. In this regard, recent guidance from the Federal Reserve may have the effect of limiting our ability to pay dividends to the extent that our earnings do not support the payment of dividends. There can be no assurance that we will be able to continue to pay quarterly cash dividends.

In addition, pursuant to the terms of our Series A Preferred Stock, we are unable to declare dividend payments on our common shares if we are in arrears on the payment of dividends on the Series A Preferred Stock. Further, for three years after the original issuance we are not permitted to increase dividends on our common shares above the amount of the last quarterly cash dividend per share declared prior to October 14, 2008 without the Treasury’s approval unless all of the Series A Preferred Stock has been redeemed or transferred by the Treasury to unaffiliated third parties.

Our ability to repurchase our shares is restricted.

The consent of the Treasury generally is required for us to make any stock repurchase (other than in connection with the administration of any employee benefit plan in the ordinary course of business and consistent with past practice and other exemptions described on page S-18 under the caption “Description of Capital Stock—Series A Preferred Stock—Priority of Dividends”), unless all of the Series A Preferred Stock has been redeemed or transferred by the Treasury to unaffiliated third parties. Further, common shares, junior preferred shares or pari passu preferred shares may not be repurchased if we are in arrears on the payment of Series A Preferred Stock dividends.

We have various anti-takeover measures that could impede a takeover.

Our articles of incorporation include certain provisions that could make more difficult the acquisition of us by means of a tender offer, a proxy contest, merger or otherwise. These provisions include certain non-monetary factors that our board of directors may consider when evaluating a takeover offer, and a requirement that any “Business Combination” be approved by the affirmative vote of no less than 66 ²/3% of the total shares attributable to persons other than a “Control Person.” These provisions and certain provisions of Washington law regarding business combinations of Washington corporations that have a class of voting stock registered under the Exchange Act, as we do, are summarized in the accompanying prospectus. See “Description of Securities—Antitakeover Effects of Certain Provisions in our Articles, Bylaws and Washington Law” on page B-6 of the accompanying prospectus. These provisions may have the effect of lengthening the time required for a person to acquire control of us though a tender offer, proxy contest or otherwise, and may deter any potentially hostile offers or other efforts to obtain control of us. This could deprive our shareholders of opportunities to realize a premium for their Columbia common stock, even in circumstances where such action is favored by a majority of our shareholders.

 

S-14

---

Table of Contents

USE OF PROCEEDS

We expect to receive net proceeds from the sale of common stock offered hereby of approximately $98.6 million (or approximately $113.4 million if the underwriters exercise their over-allotment option in full), after deducting underwriting discounts and commissions and estimated expenses payable by us. We intend to use the net proceeds of the offering to fund internal growth and selective acquisitions that meet our disciplined criteria and for general corporate purposes. With respect to acquisitions, we may use proceeds of the offering to take advantage of opportunities such as FDIC-assisted acquisitions. Depending on our evaluation of the optimal use of the proceeds of the offering, we may determine to apply proceeds to the repurchase of all or a portion of the Series A Preferred Stock we have issued to the Treasury. Pending allocation to specific uses, we intend to invest the proceeds in short-term interest-bearing investment grade securities.

 

S-15

---

Table of Contents

CAPITALIZATION

The following table shows our consolidated capitalization (unaudited) as of June 30, 2009 and to give effect to the issuance of the common stock offered hereby. You should read the following table with the consolidated financial statements and notes which are incorporated by reference into this prospectus supplement.

 

		As of June 30, 2009 (unaudited)
		Actual				As Adjusted(1)
		(dollars in thousands, except per share data)
Long-term debt:
Long-term subordinated debt		$	25,636			$	25,636
Shareholders’ equity:
Preferred stock (no par value); 2,000,000 shares authorized; 76,898 outstanding, liquidation preference of $1,000 per share			74,015				74,015
Common stock (no par value); 63,032,681 shares authorized; 18,264,060 shares outstanding; 26,764,060 shares outstanding, as adjusted			234,016				332,616
Retained earnings			95,939				95,939
Accumulated other comprehensive income			7,901				7,901
Total shareholders’ equity		$	411,871			$	510,471
Book value per share		$	18.50			$	16.31
Tangible common book value per share(2)		$	12.97			$	12.54
Equity to total assets			13.63	%			16.36	%
Tangible common equity to tangible assets(3)			8.11	%			11.11	%
Regulatory capital ratios(4):
Total risk-based capital ratio			14.61	%			18.63	%
Tier 1 risk-based capital ratio			13.35	%			17.37	%
Leverage ratio			11.22	%			14.59	%

 

(1)	Assumes that 8,500,000 shares of our common stock are sold in this offering at $12.25 per share and that the net proceeds thereof are approximately $98.6 million after deducting underwriting discounts and commissions and our estimated expenses.

 

(2)	Tangible common book value per share is defined as total shareholders’ equity, less any outstanding preferred stock, reduced by recorded goodwill and other intangible assets divided by total common shares outstanding.

 

(3)	Tangible common equity to tangible assets is defined as total shareholders’ equity, less any outstanding preferred stock, reduced by recorded goodwill and other intangible assets divided by total assets reduced by recorded goodwill and other intangible assets.

 

(4)	Represents regulatory capital ratios of Columbia Banking System, Inc.

DESCRIPTION OF CAPITAL STOCK

Our authorized capital stock consists of 63,032,681 shares of common stock, no par value per share, and 2,000,000 shares of preferred stock, no par value per share. In connection with our participation in the CPP, we have issued 76,898 shares of Series A Preferred Stock to the Treasury.

Our common stock is listed on the Nasdaq Global Select Market under the symbol “COLB.”

At June 30, 2009, there were 18,264,060 shares of our common stock issued and outstanding. On such date, 163,803 shares were subject to outstanding stock options under our employee and director stock option plans.

 

S-16

---

Table of Contents

For three years after the original issuance of our Series A Preferred Stock, we are not permitted to increase dividends on our common shares above the amount of the last quarterly cash dividend per share declared prior to October 14, 2008 without the Treasury’s approval unless all of the Series A Preferred Stock has been redeemed or transferred by the Treasury to unaffiliated third parties. In addition, the consent of the Treasury generally is required for us to make any stock repurchase (other than in connection with the administration of any employee benefit plan in the ordinary course of business and consistent with past practice and other exemptions described on page S-18 under the caption “—Series A Preferred Stock—Priority of Dividends”), unless all of the Series A Preferred Stock has been redeemed or transferred by the Treasury to unaffiliated third parties. Further, common shares, junior preferred shares or pari passu preferred shares may not be repurchased if we are in arrears on the payment of Series A Preferred Stock dividends. Other material features and rights of our common stock are described under “Description of Securities” on page B-5 of the accompanying prospectus.

Preferred Stock

General

We are authorized to issue 2,000,000 shares of preferred stock, no par value per share, 76,898 shares of which have been designated as Fixed Rate Cumulative Perpetual Preferred Stock, Series A (the “Series A Preferred Stock”), all of which is outstanding as of the date of this prospectus supplement. We do not have any other preferred stock outstanding.

Our board of directors is authorized, without further shareholder action, to issue additional preferred stock with such designations, preferences and rights as our board of directors may determine.

Series A Preferred Stock

Dividends Payable on Shares of Series A Preferred Stock

Holders of shares of Series A Preferred Stock are entitled to receive if, as and when declared by our board of directors or a duly authorized committee of the board, out of assets legally available for payment, cumulative cash dividends at a rate per annum of 5% per share on a liquidation preference of $1,000 per share of Series A Preferred Stock with respect to each dividend period from November 21, 2008, to, but excluding, November 15, 2013. From and after November 15, 2013, holders of shares of Series A Preferred Stock are entitled to receive cumulative cash dividends at a rate per annum of 9% per share on a liquidation preference of $1,000 per share of Series A Preferred Stock with respect to each dividend period thereafter.

Dividends are payable quarterly in arrears on each February 15, May 15, August 15 and November 15, each a dividend payment date, starting with February 15, 2009. Dividends payable during any dividend period are computed on the basis of a 360-day year consisting of twelve 30-day months. Dividends payable with respect to the Series A Preferred Stock are payable to holders of record of shares of Series A Preferred Stock on the date that is 15 calendar days immediately preceding the applicable dividend payment date or such other record date as the board of directors or any duly authorized committee of the board determines, so long as such record date is not more than 60 nor less than 10 days prior to the applicable dividend payment date.

If we determine not to pay any dividend or a full dividend with respect to the Series A Preferred Stock, we are required to provide written notice to the holders of shares of Series A Preferred Stock prior to the applicable dividend payment date.

We are subject to various regulatory policies and requirements relating to the payment of dividends, including requirements to maintain adequate capital above regulatory minimums. The Board of Governors of the Federal Reserve System is authorized to determine, under certain circumstances relating to the financial condition of a bank holding company, such as us, that the payment of dividends would be an unsafe or unsound practice and to prohibit payment thereof. In addition, we are subject to Washington state laws relating to the payment of dividends.

 

S-17

---

Table of Contents

Priority of Dividends

With respect to the payment of dividends and the amounts to be paid upon liquidation, the Series A Preferred Stock will rank:

 

•

senior to our common stock and all other equity securities designated as ranking junior to the Series A Preferred Stock; and

 

•

at least equally with all other equity securities designated as ranking on a parity with the Series A Preferred Stock, or parity stock, with respect to the payment of dividends and distribution of assets upon any liquidation, dissolution or winding-up of us.

So long as any shares of Series A Preferred Stock remain outstanding, unless all accrued and unpaid dividends for all prior dividend periods have been paid or are contemporaneously declared and paid in full, no dividend whatsoever shall be paid or declared on our common stock or other junior stock, other than a dividend payable solely in common stock. We and our subsidiaries also may not purchase, redeem or otherwise acquire for consideration any shares of our common stock or other junior stock unless we have paid in full all accrued dividends on the Series A Preferred Stock for all prior dividend periods, other than:

 

•

purchases, redemptions or other acquisitions of our common stock or other junior stock in connection with the administration of our employee benefit plans in the ordinary course of business and consistent with past practice, including purchases pursuant to a publicly announced repurchase plan up to the increase in diluted shares outstanding resulting from the grant, vesting or exercise of equity-based compensation;

 

•

purchases or other acquisitions by one of our broker-dealer subsidiaries solely for the purpose of market-making, stabilization or customer facilitation transactions in junior stock or parity stock in the ordinary course of its business;

 

•

purchases by one of our broker-dealer subsidiaries of our capital stock for resale pursuant to an offering by us of such stock that is underwritten by such broker-dealer subsidiary;

 

•

any dividends or distributions of rights on junior stock in connection with any stockholders’ rights plan or any redemption or repurchases of rights pursuant to any stockholders’ rights plan;

 

•

acquisition by us or any of our subsidiaries of record ownership of junior stock or parity stock for the beneficial ownership of any other person other than us or one of our subsidiaries, including as trustee or custodian; and

 

•

the exchange or conversion of junior stock for or into other junior stock or of parity stock for or into other parity stock or junior stock but only to the extent that such acquisition is required pursuant to binding contractual agreements entered into before November 21, 2008 or any subsequent agreement for the accelerated exercise, settlement or exchange thereof for common stock.

Until such time as the initial selling securityholder ceases to own any shares of Series A Preferred Stock, if we repurchase shares of Series A Preferred Stock from a holder who is not the initial selling securityholder, other than permitted repurchases, we must offer to repurchase a ratable portion of the Series A Preferred Stock then held by the initial selling securityholder.

On any dividend payment date for which full dividends are not paid, or declared and funds set aside therefor, on the Series A Preferred Stock and any other parity stock, all dividends paid or declared for payment on that dividend payment date (or, with respect to parity stock with a different dividend payment date, on the applicable dividend date therefor falling within the dividend period and related to the dividend payment date for the Series A Preferred Stock), with respect to the Series A Preferred Stock and any other parity stock shall be declared ratably among the holders of any such shares who have the right to receive dividends, in proportion to the respective amounts of the undeclared and unpaid dividends relating to the dividend period.

 

S-18

---

Table of Contents

Subject to the immediately preceding paragraph, such dividends (payable in cash, securities or otherwise) as may be determined by our board of directors (or a duly authorized committee of the board) may be declared and paid on our common stock and any other stock ranking junior to the Series A Preferred Stock from time to time out of any funds legally available for such payment, and the Series A Preferred Stock shall not be entitled to participate in any such dividend.

Redemption

The Series A Preferred Stock may be redeemed at any time, subject to the approval of the Federal Reserve Board, in whole or in part (but at least 25%), subject to notice as described below.

In any redemption, the redemption price is an amount equal to the per share liquidation amount plus accrued and unpaid dividends to but excluding the date of redemption.

The Series A Preferred Stock will not be subject to any mandatory redemption, sinking fund or similar provisions. Holders of shares of Series A Preferred Stock have no right to require the redemption or repurchase of the Series A Preferred Stock.

If fewer than all of the outstanding shares of Series A Preferred Stock are to be redeemed, the shares to be redeemed will be selected either pro rata from the holders of record of shares of Series A Preferred Stock in proportion to the number of shares held by those holders or in such other manner as our board of directors or a committee thereof may determine to be fair and equitable.

We will mail notice of any redemption of Series A Preferred Stock by first class mail, postage prepaid, addressed to the holders of record of the shares of Series A Preferred Stock to be redeemed at their respective last addresses appearing on our books. This mailing will be at least 30 days and not more than 60 days before the date fixed for redemption. Each notice of redemption will set forth the applicable redemption date, the redemption price, the place where shares of Series A Preferred Stock are to be redeemed, and the number of shares of Series A Preferred Stock to be redeemed (and, if less than all shares of Series A Preferred Stock held by the applicable holder, the number of shares to be redeemed from the holder).

Shares of Series A Preferred Stock that are redeemed, repurchased or otherwise acquired by us will revert to authorized but unissued shares of our preferred stock.

Liquidation Rights

In the event that we voluntarily or involuntarily liquidate, dissolve or wind up our affairs, holders of Series A Preferred Stock will be entitled to receive an amount per share, referred to as the total liquidation amount, equal to the fixed liquidation preference of $1,000 per share, plus any accrued and unpaid dividends, whether or not declared, to the date of payment. Holders of the Series A Preferred Stock will be entitled to receive the total liquidation amount out of our assets that are available for distribution to stockholders, after payment or provision for payment of our debts and other liabilities but before any distribution of assets is made to holders of our common stock or any other shares ranking, as to that distribution, junior to the Series A Preferred Stock.

If our assets are not sufficient to pay the total liquidation amount in full to all holders of Series A Preferred Stock and all holders of any shares of outstanding parity stock, the amounts paid to the holders of Series A Preferred Stock and other shares of parity stock will be paid pro rata in accordance with the respective total liquidation amount for those holders. If the total liquidation amount per share of Series A Preferred Stock has been paid in full to all holders of Series A Preferred Stock and other shares of parity stock, the holders of our common stock or any other shares ranking, as to such distribution, junior to the Series A Preferred Stock will be entitled to receive all of our remaining assets according to their respective rights and preferences.

 

S-19

---

Table of Contents

For purposes of the liquidation rights, neither the sale, lease or exchange (for cash, securities or other property) of all or substantially all of our assets, nor the consolidation or merger by us with or into any other corporation or any other entity or by another corporation or any other entity with or into us, will constitute a liquidation, dissolution or winding-up of our affairs.

Voting Rights

Except as indicated below or otherwise required by law, the holders of Series A Preferred Stock will not have any voting rights.

Election of Two Directors upon Non-Payment of Dividends. If the dividends on the Series A Preferred Stock have not been paid for an aggregate of six quarterly dividend periods or more (whether or not consecutive), the authorized number of directors then constituting our board of directors will be increased by two. Holders of Series A Preferred Stock, together with the holders of any outstanding parity stock with like voting rights, referred to as voting parity stock, voting as a single class, will be entitled to elect the two additional members of our board of directors, referred to as the preferred stock directors, at the next annual meeting (or at a special meeting called for the purpose of electing the preferred stock directors prior to the next annual meeting) and at each subsequent annual meeting until all accrued and unpaid dividends for all past dividend periods have been paid in full. The election of any preferred stock director is subject to the qualification that the election would not cause us to violate the corporate governance requirement of the Nasdaq Stock Market (or any other exchange or quotation service on which our securities may be listed or quoted) that listed companies must have a majority of independent directors.

Upon the termination of the right of the holders of Series A Preferred Stock and voting parity stock to vote for preferred stock directors, as described above, the preferred stock directors will immediately cease to be qualified as directors, their term of office shall terminate immediately and the number of our authorized directors will be reduced by the number of preferred stock directors that the holders of Series A Preferred Stock and voting parity stock had been entitled to elect. The holders of a majority of shares of Series A Preferred Stock and voting parity stock, voting as a class, may remove any preferred stock director, with or without cause, and the holders of a majority of the shares of Series A Preferred Stock and voting parity stock, voting as a class, may fill any vacancy created by the removal of a preferred stock director. If the office of a preferred stock director becomes vacant for any other reason, the remaining preferred stock director may choose a successor to fill such vacancy for the remainder of the unexpired term.

Other Voting Rights. So long as any shares of Series A Preferred Stock are outstanding, in addition to any other vote or consent of stockholders required by law or by our articles of incorporation, the vote or consent of the holders of at least 66 ²/3% of the shares of Series A Preferred Stock at the time outstanding, voting separately as a single class, given in person or by proxy, either in writing without a meeting or by vote at any meeting called for the purpose, shall be necessary for effecting or validating:

 

•

any amendment or alteration of the Certificate of Designations for the Series A Preferred Stock or our articles of incorporation to authorize or create or increase the authorized amount of, or any issuance of, any shares of, or any securities convertible into or exchangeable or exercisable for shares of, any class or series of our capital stock ranking senior to the Series A Preferred Stock with respect to payment of dividends and/or distribution of assets on any liquidation, dissolution or winding-up of us;

 

•

any amendment, alteration or repeal of any provision of the Certificate of Designations for the Series A Preferred Stock or our articles of incorporation so as to adversely affect the rights, preferences, privileges or voting powers of the Series A Preferred Stock; or

 

•

any consummation of a binding share exchange or reclassification involving the Series A Preferred Stock or of a merger or consolidation of us with another entity, unless (i) the shares of Series A Preferred Stock remain outstanding following any such transaction or, if we are not the surviving

 

S-20

---

Table of Contents

entity, are converted into or exchanged for preference securities of the surviving entity or its ultimate parent, and (ii) such remaining outstanding shares of Series A Preferred Stock or preference securities have rights, preferences, privileges and voting powers, and limitations and restrictions thereof, that are not materially less favorable than the rights, preferences, privileges or voting powers of the Series A Preferred Stock, taken as a whole.

Holders of shares of Series A Preferred Stock will be entitled to one vote for each such share on any matter on which holders of shares of Series A Preferred Stock are entitled to vote, including any action by written consent.

The foregoing voting provisions will not apply if, at or prior to the time when the vote or consent would otherwise be required, all outstanding shares of Series A Preferred Stock have been redeemed or called for redemption upon proper notice and sufficient funds have been set aside by us for the benefit of the holders of Series A Preferred Stock to effect the redemption.

Treasury Warrant

In connection with the Treasury’s purchase of our Series A Preferred Stock, we issued to the Treasury a ten-year warrant exercisable for 796,046 shares of our common stock at an initial exercise price of $14.49 (the “Warrant”).

Shares of Common Stock Subject to the Warrant

The Warrant is initially exercisable for 796,046 shares of our common stock. If we complete one or more qualified equity offerings on or prior to December 31, 2009, that result in our receipt of aggregate gross proceeds of not less than $76,898,000, which is equal to 100% of the aggregate liquidation preference of the Series A Preferred Stock, the number of shares of common stock underlying the Warrant then held by the selling securityholders will be reduced by 50%. If we elect to repurchase our Series A Preferred Stock, we will also have the right to repurchase the Warrant at fair market value, according to procedures set forth under the terms of our Series A Preferred Stock. The number of shares subject to the Warrant are subject to the further adjustments described below under the heading “—Adjustments to the Warrant.”

Exercise of the Warrant

The initial exercise price applicable to the Warrant is $14.49 per share of common stock for which the Warrant may be exercised. The Warrant may be exercised at any time on or before November 21, 2018 by surrender of the Warrant and a completed notice of exercise attached as an annex to the Warrant and the payment of the exercise price for the shares of common stock for which the Warrant is being exercised. The exercise price may be paid either by the withholding of such number of shares of common stock issuable upon exercise of the Warrant equal to the value of the aggregate exercise price of the Warrant determined by reference to the market price of our common stock on the trading day on which the Warrant is exercised or, if agreed to by us and the warrantholder, by the payment of cash equal to the aggregate exercise price. The exercise price applicable to the Warrant is subject to the further adjustments described below under the heading “—Adjustments to the Warrant.”

Upon exercise of the Warrant, certificates for the shares of common stock issuable upon exercise will be issued to the warrantholder. We will not issue fractional shares upon any exercise of the Warrant. Instead, the warrantholder will be entitled to a cash payment equal to the market price of our common stock on the last trading day preceding the date of exercise of the Warrant (less the pro-rated exercise price of the Warrant) for any fractional shares that would have otherwise been issuable upon exercise of the Warrant. We will at all times reserve the aggregate number of shares of our common stock for which the Warrant may be exercised. The shares of common stock issuable upon exercise of the Warrant have been listed for quotation on the Nasdaq Stock Market.

 

S-21

---

Table of Contents

Rights as a Shareholder

The warrantholder shall have no rights or privileges of the holders of our common stock, including any voting rights, until (and then only to the extent) the Warrant has been exercised.

Transferability

The initial selling securityholder may not transfer a portion of the Warrant with respect to more than 50% of shares of common stock until the earlier of the date on which the Company has received aggregate gross proceeds from one or more qualified equity offerings of at least $76,898,000 and December 31, 2009. This offering will be a qualified equity offering described in the immediately preceding sentence. If we elect to repurchase our Series A Preferred Stock, we will also have the right to repurchase the Warrant at fair market value. If we elect to repurchase our Series A Preferred Stock but do not elect to repurchase the Warrant, we will be required to issue a substitute warrant to the Treasury that the Treasury may exercise or transfer to a third party.

Adjustments to the Warrant

Adjustments in Connection with Stock Splits, Subdivisions, Reclassifications and Combinations. The number of shares for which the Warrant may be exercised and the exercise price applicable to the Warrant will be proportionately adjusted in the event we pay dividends or make distributions of our common stock, subdivide, combine or reclassify outstanding shares of our common stock.

Anti-dilution Adjustment. Until the earlier of November 21, 2011 and the date on which the initial selling securityholder no longer holds the Warrant or any portion of the Warrant (and other than in certain permitted transactions described below), if we issue any shares of common stock (or securities convertible or exercisable into common stock) without consideration or for less than 90% of the market price of the common stock on the last trading day prior to the date of the agreement on pricing such shares, then the number of shares of common stock into which the Warrant is exercisable and the exercise price will be adjusted. Permitted transactions include issuances:

 

•

as consideration for or to fund the acquisition of businesses and/or related assets;

 

•

in connection with employee benefit plans and compensation related arrangements in the ordinary course and consistent with past practice approved by our board of directors;

 

•

in connection with public or broadly marketed offerings and sales of common stock or convertible securities for cash conducted by us or our affiliates pursuant to registration under the Securities Act or Rule 144A thereunder on a basis consistent with capital-raising transactions by comparable financial institutions; and

 

•

in connection with the exercise of preemptive rights on terms existing as of November 21, 2008.

Other Distributions. If we declare any dividends or distributions other than our historical, ordinary cash dividends, the exercise price of the Warrant will be adjusted to reflect such distribution.

Certain Repurchases. If we effect a pro rata repurchase of common stock, both the number of shares issuable upon exercise of the Warrant and the exercise price will be adjusted.

Business Combinations. In the event of a merger, consolidation or similar transaction involving Columbia and requiring stockholder approval, the warrantholder’s right to receive shares of our common stock upon exercise of the Warrant shall be converted into the right to exercise the Warrant for the consideration that would have been payable to the warrantholder with respect to the shares of common stock for which the Warrant may be exercised, as if the Warrant had been exercised prior to such merger, consolidation or similar transaction.

 

S-22

---

Table of Contents

CERTAIN UNITED STATES TAX CONSEQUENCES TO NON-U.S. HOLDERS OF COMMON STOCK

This section summarizes certain United States federal income and estate tax consequences of the ownership and disposition of our common stock by a non-U.S. holder. You are a non-U.S. holder if you are a beneficial owner of our common stock and are not, for United States federal income tax purposes:

 

•

an individual who is a citizen or resident of the United States;

 

•

a corporation, or other entity treated as a corporation for U.S. federal income tax purposes, created or organized in or under the laws of the United States, any State thereof or the District of Columbia;

 

•

an estate the income of which is subject to U.S. federal income taxation regardless of its source; or

 

•

a trust if (i) the administration of the trust is subject to the primary supervision of a court in the United States and for which one or more U.S. persons have the authority to control all substantial decisions or (ii) it has a valid election in effect to be treated as a United States person.

This section does not consider the specific facts and circumstances that may be relevant to a particular non-U.S. holder, including certain former U.S. citizens or long-term residents, and does not address the treatment of a non-U.S. holder under the laws of any state, local or foreign taxing jurisdiction. This section is based on the tax laws of the United States, including the Internal Revenue Code of 1986, as amended, existing and proposed regulations, and administrative and judicial interpretations, all as currently in effect. These laws are subject to change, possibly on a retroactive basis.

If a partnership holds our common stock, the United States federal income tax treatment of a partner will generally depend on the status of the partner and the tax treatment of the partnership. A partner in a partnership holding our common stock should consult its tax advisor with regard to the United States federal income tax treatment of an investment in our common stock.

You should consult a tax advisor regarding the United States federal tax consequences of acquiring, holding and disposing of our common stock in your particular circumstances, as well as any tax consequences that may arise under the laws of any state, local or foreign taxing jurisdiction.

Dividends

Except as described below, if you are a non-U.S. holder of our common stock, dividends paid to you are subject to withholding of United States federal income tax at a 30% rate or at a lower rate if you are eligible for the benefits of an income tax treaty that provides for a lower rate. Even if you are eligible for a lower treaty rate, we and other payors will generally be required to withhold at a 30% rate (rather than the lower treaty rate) on dividend payments to you, unless you have furnished to us or another payor:

 

•

a valid Internal Revenue Service Form W-8BEN or an acceptable substitute form upon which you certify, under penalties of perjury, your status as (or, in the case of a United States alien holder that is a partnership or an estate or trust, such forms certifying the status of each partner in the partnership or beneficiary of the estate or trust as) a non-United States person and your entitlement to the lower treaty rate with respect to such payments, or

 

•

in the case of payments made outside the United States to an offshore account (generally, an account maintained by you at an office or branch of a bank or other financial institution at any location outside the United States), other documentary evidence establishing your entitlement to the lower treaty rate in accordance with U.S. Treasury regulations.

If you are eligible for a reduced rate of United States withholding tax under a tax treaty, you may obtain a refund of any amounts withheld in excess of that rate by filing a refund claim with the United States Internal Revenue Service.

 

S-23

---

Table of Contents

If dividends paid to you are “effectively connected” with your conduct of a trade or business within the United States, and, if required by an applicable income tax treaty, the dividends are attributable to a permanent establishment that you maintain in the United States, we and other payors generally are not required to withhold tax from the dividends, provided that you have furnished to us or another payor a valid Internal Revenue Service Form W-8ECI or an acceptable substitute form upon which you represent, under penalties of perjury, that:

 

•

you are a non-United States person, and

 

•

the dividends are effectively connected with your conduct of a trade or business within the United States and are includible in your gross income.

“Effectively connected” dividends are taxed at rates applicable to United States citizens, resident aliens and domestic United States corporations.

If you are a corporate non-U.S. holder, “effectively connected” dividends that you receive may, under certain circumstances, be subject to an additional “branch profits tax” at a 30% rate or at a lower rate if you are eligible for the benefits of an income tax treaty that provides for a lower rate.

Gain on Disposition of Common Stock

If you are a non-U.S. holder, you generally will not be subject to United States federal income tax on gain that you recognize on a disposition of our common stock unless:

 

•

the gain is “effectively connected” with your conduct of a trade or business in the United States, and the gain is attributable to a permanent establishment that you maintain in the United States, if that is required by an applicable income tax treaty as a condition for subjecting you to United States taxation on a net income basis,

 

•

you are an individual, you hold our common stock as a capital asset, you are present in the United States for 183 or more days in the taxable year of the sale and certain other conditions exist, or

 

•

we are or have been a United States real property holding corporation (“USRPHC”) for federal income tax purposes. We currently believe that we are not, and that we are unlikely to become a USRPHC in the future.

If you are a corporate non-U.S. holder, “effectively connected” gains that you recognize may also, under certain circumstances, be subject to an additional “branch profits tax” at a 30% rate or at a lower rate if you are eligible for the benefits of an income tax treaty that provides for a lower rate.

Federal Estate Taxes

Common stock held by a non-U.S. holder at the time of death will be included in the holder’s gross estate for United States federal estate tax purposes, unless an applicable estate tax treaty provides otherwise.

Backup Withholding and Information Reporting

We must report annually to the Internal Revenue Service and to each non-U.S. holder the amount of dividends paid to that holder and the tax withheld from those dividends. These reporting requirements apply regardless of whether withholding was reduced or eliminated by an applicable tax treaty. Copies of the information returns reporting those dividends and withholding may also be made available to the tax authorities in the country in which the non-U.S. holder is a resident under the provisions of an applicable income tax treaty or agreement.

Under some circumstances, U.S. Treasury regulations require additional information reporting and backup withholding on dividend payments on common stock. The gross amount of dividends paid to a non-U.S. holder

 

S-24

---

Table of Contents

that fails to certify its non-U.S. holder status in accordance with applicable U.S. Treasury regulations and does not otherwise establish an exemption from backup withholding generally will be subject to backup withholding at the applicable rate, currently 28%.

The payment of the proceeds of the sale or other disposition of common stock (including a redemption) by a non-U.S. holder through the U.S. office of any broker, U.S. or foreign, generally will be reported to the Internal Revenue Service and subject to backup withholding, unless the non-U.S. holder either certifies its status as a non-U.S. holder under penalties of perjury or otherwise establishes an exemption. The payment of the proceeds of the disposition of common stock by a non-U.S. holder through a non-U.S. office of a non-U.S. broker will not be subject to backup withholding or reported to the Internal Revenue Service, unless the non-U.S. broker has certain enumerated connections with the United States. In general, the payment of proceeds from the disposition of common stock through a non-U.S. office of a broker that is a U.S. person or has certain enumerated connections with the United States will be reported to the Internal Revenue Service (but will not be subject to backup withholding), unless the broker receives a statement from the non-U.S. holder that certifies its status as a non-U.S. holder under penalties of perjury or the broker has documentary evidence in its files that the holder is a non-U.S. holder.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a non-U.S. holder can be refunded or credited against the non-U.S. holder’s U.S. federal income tax liability, if any, provided that the required information is furnished to the Internal Revenue Service in a timely manner. These backup withholding and information reporting rules are complex and non-U.S. holders are urged to consult their own advisors regarding the application of these rules to them.

 

S-25

---

Table of Contents

UNDERWRITING

We are offering the shares of our common stock described in this prospectus through Keefe, Bruyette & Woods, Inc., and D.A. Davidson & Co., as representatives of the underwriters (the “Underwriters”). We have entered into an underwriting agreement with the Underwriters, dated August 5, 2009 (the “Underwriting Agreement”). Subject to the terms and conditions of the Underwriting Agreement, each of the Underwriters has severally agreed to purchase the number of shares of common stock listed next to its name in the following table:

 

Underwriter of Shares		Number
Keefe, Bruyette & Woods, Inc.		5,950,000
D.A. Davidson & Co.		2,550,000
Total		8,500,000

Our common stock is offered subject to a number of conditions, including receipt and acceptance of the common stock by the Underwriters.

In connection with this offering, the Underwriters or securities dealers may distribute prospectuses electronically.

Director and Officer Participation

Our management, directors, principal stockholders, or their affiliates may acquire shares in this offering. Furthermore, any purchases by management, directors, principal stockholders, or their affiliates must be made on the same terms and conditions as purchases by nonaffiliated investors and with a view toward investment, not resale.

Over-allotment Option

We have granted to the Underwriters an option to buy 1,275,000 additional shares of our common stock. The Underwriters may exercise this option solely for the purpose of covering over-allotments, if any, made in connection with this offering. The Underwriters have thirty (30) days from the date of this prospectus to exercise this option.

Commissions and Discounts

Shares of common stock sold by the Underwriters to the public will initially be offered at the offering price set forth on the cover of this prospectus. Any shares of common stock sold by the Underwriters to securities dealers may be sold at a discount of up to $0.3675 per share from the public offering price. Any of these securities dealers may resell any shares of common stock purchased from the Underwriters to other brokers or dealers at a discount of up to $0.10 per share from the public offering price. If all the shares of common stock are not sold at the public offering price, the representatives may change the offering price and the other selling terms. Sales of shares of common stock made outside of the United States may be made by affiliates of the Underwriters.

The following table shows the per share and total underwriting discounts and commissions we will pay to the Underwriters, assuming both no exercise and full exercise of the Underwriters’ option to purchase an additional 1,275,000 shares of common stock:

 

		No Exercise			Full Exercise
Per Share Total		$	0.6125		$	0.6125
Total		$	5,206,250		$	5,987,188

 

S-26

---

Table of Contents

We estimate that the total expenses of this offering payable by us, not including the underwriting discounts and commissions, will be approximately $319,000.

For a period of twelve months from July 30, 2009, we have granted to Keefe, Bruyette & Woods, Inc., the right of first refusal to act as our lead financial advisor, lead book running manager underwriter or lead purchaser or placement agent in connection with any restructuring transaction, any public offering, any Rule 144A offering or any private placement of securities, subject to certain conditions. In addition, we have agreed to reimburse Keefe, Bruyette & Woods, Inc., for certain expenses incurred by them in connection with the offering, the amount of such expenses not to exceed $75,000 without our prior written approval.

No Sales of Similar Securities

We and our executive officers and directors have entered into lock-up agreements with the Underwriters. Under these agreements, we and each of these persons may not, without the prior written approval of the representatives, subject to limited exceptions, offer, sell, contract to sell or otherwise dispose of or hedge our common stock or securities convertible into or exercisable or exchangeable for our common stock. These restrictions will be in effect for a period of ninety (90) days after the date of this prospectus. At any time and without public notice, the representatives may, in their sole discretion, release all or some of the securities from these lock-up agreements.

Indemnification and Contribution

We have agreed to indemnify the Underwriters and their affiliates and controlling persons against certain liabilities. If we are unable to provide this indemnification, we will contribute to the payments the Underwriters, their affiliates and their controlling persons may be required to make in respect of those liabilities.

Nasdaq Listing

Our common stock is quoted on the Nasdaq Global Select Market under the symbol “COLB.”

Price Stabilization and Short Positions

In connection with this offering, the Underwriters may engage in activities that stabilize, maintain or otherwise affect the price of our common stock, including:

 

•

stabilizing transactions;

 

•

short sales; and

 

•

purchases to cover positions created by short sales.

Stabilizing transactions consist of bids or purchases made for the purpose of preventing or retarding a decline in the market price of our common stock while this offering is in progress. These transactions may also include making short sales of our common stock, which involve the sale by the Underwriters of a greater number of shares of common stock than they are required to purchase in this offering. Short sales may be “covered short sales,” which are short positions in an amount not greater than the Underwriters’ over-allotment option referred to above, or may be “naked short sales,” which are short positions in excess of that amount.

The Underwriters may close out any covered short position either by exercising their over-allotment option, in whole or in part, or by purchasing shares in the open market. In making this determination, the Underwriters will consider, among other things, the price of shares available for purchase in the open market compared to the price at which they may purchase shares through the over-allotment option. The Underwriters must close out any naked short position by purchasing shares in the open market. A naked short position is more likely to be created if the Underwriters are concerned that there may be downward pressure on the price of the common stock in the open market that could adversely affect investors who purchased in this offering.

 

S-27

---

Table of Contents

As a result of these activities, the price of our common stock may be higher than the price that otherwise might exist in the open market. If these activities are commenced, they may be discontinued by the Underwriters at any time. The Underwriters may carry out these transactions on the Nasdaq, in the over-the-counter market or otherwise.

Affiliations

The Underwriters and their affiliates have provided and may continue to provide certain commercial banking, financial advisory and investment banking services for us for which they receive fees.

The Underwriters and their affiliates may from time to time in the future engage in transactions with us and perform services for us in the ordinary course of their business.

Selling Restrictions

European Economic Area

In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a Relevant Member State), each Underwriter has represented and agreed that with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State (the Relevant Implementation Date) it has not made and will not make an offer of shares to the public in that Relevant Member State prior to the publication of a prospectus in relation to the shares which has been approved by the competent authority in that Relevant Member State or, where appropriate, approved in another Relevant Member State and notified to the competent authority in that Relevant Member State, all in accordance with the Prospectus Directive, except that it may, with effect from and including the Relevant Implementation Date, make an offer of shares to the public in that Relevant Member State at any time:

 

(a)

to legal entities which are authorized or regulated to operate in the financial markets or, if not so authorized or regulated, whose corporate purpose is solely to invest in securities;

 

(b)

to any legal entity which has two or more of (1) an average of at least 250 employees during the last financial year; (2) a total balance sheet of more than €43,000,000; and (3) an annual net turnover of more than €50,000,000, as shown in its last annual or consolidated accounts;

 

(c)

to fewer than 100 natural or legal persons (other than qualified investors as defined in the Prospectus Directive); or

 

(d)

in any other circumstances which do not require the publication by the Issuer of a prospectus pursuant to Article 3 of the Prospectus Directive.

For the purposes of this provision, the expression an “offer of shares to the public” in relation to any shares in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the shares to be offered so as to enable an investor to decide to purchase or subscribe for the shares, as the same may be varied in that Relevant Member State by any measure implementing the Prospectus Directive in that Relevant Member State, and the expression Prospectus Directive means Directive 2003/71/EC and includes any relevant implementing measure in each Relevant Member State.

United Kingdom

Each Underwriter has represented and agreed that:

 

(a)

it has only communicated or caused to be communicated and will only communicate or cause to be communicated an invitation or inducement to engage in investment activity (within the meaning of Section 21 of the Financial Services and Markets Act 2000, as amended (the “FSMA”)) received by it in connection with the issue or sale of the shares in circumstances in which Section 21(1) of the FSMA does not apply to the Issuer; and

 

(b)

it has complied and will comply with all applicable provisions of the FSMA with respect to anything done by it in relation to the shares in, from or otherwise involving the United Kingdom.

 

S-28

---

Table of Contents

LEGAL MATTERS

Certain legal matters with respect to the validity of the common stock offered hereby have been passed upon for us by Graham & Dunn PC. Pillsbury Winthrop Shaw Pittman LLP is acting as counsel for the underwriters in connection with certain legal matters relating to the shares of common stock offered hereby.

EXPERTS

Our consolidated financial statements appearing in our Annual Report on Form 10-K for the year ended December 31, 2008, and the effectiveness of Columbia Banking System, Inc.’s internal control over financial reporting, have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports, which are incorporated herein by reference. Such financial statements have been so incorporated in reliance upon the reports of such firm given upon their authority as experts in accounting and auditing.

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to incorporate by reference information into this prospectus. This means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be part of this prospectus, except for any information that is superceded by subsequent incorporated documents or by information that is included directly in this prospectus or any prospectus supplement. We incorporate by reference the documents listed below and any future filings we make with the SEC after the date of this prospectus and until the termination of this offering under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act:

 

•

Annual Report on Form 10-K for the year ended December 31, 2008, filed February 27, 2009 (including those portions of our Proxy Statement on Schedule 14A relating to our 2009 Annual Meeting of Stockholders, which was filed on March 23, 2009, incorporated by reference therein) except the Five-Year Stock Performance Graph and related discussion appearing in Part II, Item 5;

 

•

Quarterly Reports on Form 10-Q for the quarter ended March 31, 2009, filed May 6, 2009; and the quarter ended June 30, 2009, filed July 31, 2009;

 

•

Current Reports on Form 8-K filed June 2, 2009, June 29, 2009 and August 5, 2009; and

 

•

The description of our common stock contained in our Current Report on Form 8-K filed June 29, 2009, including any amendment or report filed to update such description.

Nothing in this prospectus supplement shall be deemed to incorporate information deemed furnished but not filed with the SEC.

You may obtain any of these incorporated documents from us without charge, excluding any exhibits to those documents unless the exhibit is specifically incorporated by reference in such document. You may obtain documents incorporated by reference in this prospectus supplement by requesting them from us in writing or by telephone at the following address:

Columbia Banking System, Inc.
1301 “A” Street
Tacoma, Washington 98402-4200
(253) 305-1900
Attention: Cathleen Dent, Corporate Secretary

In addition, we maintain a corporate website, www.columbiabank.com. We make available through our website our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and any amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. This reference to our website is for the convenience of investors as required by the SEC and shall not be deemed to incorporate any information on the website into this prospectus supplement.

 

S-29

---

Table of Contents

PROSPECTUS

$100,000,000

COLUMBIA BANKING SYSTEM, INC

Common Stock

Preferred Stock

 

 

We may offer and sell, from time to time in one or more offerings and in amounts, at prices and on terms that will be determined at the time of any such offering, shares of our common stock, no par value per share and shares of our preferred stock, no par value per share.

Each time we sell shares, we will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add, update or change information contained in this prospectus. This prospectus may not be used to offer or sell our common stock or preferred stock without a prospectus supplement describing the method and terms of the offering. You should read both this prospectus and any prospectus supplement together with the additional information described under the heading “Incorporation of Certain Documents by Reference” before you make your investment decision.

We may sell our shares on a continuous or delayed basis directly, through agents or underwriters as designated from time to time, or through a combination of these methods. For additional information on the method of sale, you should refer to the section of this prospectus entitled “Plan of Distribution” on page B-4. We reserve the sole right to accept, and together with any agents, dealers and underwriters, reserve the right to reject, in whole or in part, any proposed purchase of our shares. If any agents, dealers or underwriters are involved in the sale of our shares, the applicable prospectus supplement will set forth any applicable commissions or discounts. Our net proceeds from the sale of our shares will also be set forth in the applicable prospectus supplement.

Our common stock is traded on the NASDAQ Global Select Market under the symbol “COLB.”

Investing in our securities involves a high degree of risk. See “Risk Factors” on page B-1 of this prospectus, as well as in supplements to this prospectus.

These securities are not deposits or obligations of a bank or savings association and are not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus or the accompanying prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is November 3, 2008.

---

Table of Contents

TABLE OF CONTENTS

 

About this Prospectus		B-1
Risk Factors		B-1
Cautionary Note Regarding Forward-Looking Statements		B-1
Where You Can Find More Information		B-2
Incorporation of Certain Documents By Reference		B-3
About Columbia		B-3
Use of Proceeds		B-4
Plan of Distribution		B-4
Description of Securities		B-5
Legal Matters		B-8
Experts		B-8

 

i

---

Table of Contents

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, which we refer to as the “SEC,” utilizing a “shelf” registration process. Under this shelf registration process, we may offer and sell the securities described in this prospectus in one or more offerings. This prospectus only provides you with a general description of the securities that we may offer. Each time we offer our securities, we will provide a prospectus supplement and attach it to this prospectus. The prospectus supplement will contain specific information about the terms of the offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and any prospectus supplement together with additional information described below under the heading “Where You Can Find More Information” and “Incorporation of Certain Documents by Reference.”

You should rely only on the information contained or incorporated by reference in this prospectus and any prospectus supplement. We have not authorized anyone to provide you with different information. We are not making offers to sell the securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making such offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation.

The information in this prospectus is accurate as of the date on the front cover. You should not assume that the information contained in this prospectus is accurate as of any other date.

Unless otherwise indicated or unless the context requires otherwise, all references in this prospectus to “Columbia,” the “Company,” “we,” “us,” “our” or similar references mean Columbia Banking System, Inc., and references to the “Bank” mean “Columbia Bank.”

RISK FACTORS

You should carefully consider the specific risks set forth under “Risk Factors” in the applicable prospectus supplement and under the caption “Risk Factors” in any of our filings with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 (“Exchange Act”) incorporated into this prospectus by reference, before making an investment decision.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, and any prospectus supplement, including information included or incorporated by reference, may contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements include, but are not limited to, statements about our plans, objectives, expectations and intentions that are not historical facts, and other statements identified by words such as “expects,” “anticipates,” “intends,” “plans,” “believes,” “should,” “projects,” “seeks,” “estimates” or words of similar meaning. These forward-looking statements are based on current beliefs and expectations of management and are inherently subject to significant business, economic and competitive uncertainties and contingencies, many of which are beyond our control. In addition, these forward-looking statements are subject to assumptions with respect to future business strategies and decisions that are subject to change. The following factors, among others, could cause actual results to differ materially from the anticipated results or other expectations in the forward-looking statements, including those set forth in this prospectus, any accompanying prospectus supplement or the documents incorporated by reference, including the “Risk Factors,” “Business” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” section of our reports and other documents filed with the SEC:

 

•

the risks associated with continued diversification of assets and potential adverse changes in credit quality;

 

•

increased delinquency rates;

 

B-1

---

Table of Contents

•

competition from other financial services companies in our markets;

 

•

the risks presented by the current economic slowdown, which could adversely affect credit quality, collateral values and loan originations;

 

•

our ability to obtain applicable regulatory and shareholder approvals necessary to complete a pending acquisition and the ability to consummate that pending acquisition;

 

•

demand for banking products and services may decline;

 

•

legislative or regulatory changes that adversely affect our business; and

 

•

our success in managing risks involved in the foregoing.

Additional factors that could cause actual results to differ materially from those expressed in the forward-looking statements are discussed in “Risk Factors” above, in our prospectus supplement and in our reports filed with the SEC. We believe the expectations reflected in our forward-looking statements are reasonable, based on information available to us on the date hereof. However, given the described uncertainties and risks, we cannot guarantee our future performance or results of operations and you should not place undue reliance on these forward-looking statements. We undertake no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. The risks described in our other SEC filings and our prospectus supplement should be considered when reading any forward-looking statements in this document.

WHERE YOU CAN FIND MORE INFORMATION

We are a reporting company and file annual, quarterly and current reports, proxy information and other information with the SEC. You may read and copy such material at the Public Reference Room maintained by the SEC at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for more information on the operation of the Public Reference Room.

The SEC also maintains an internet world wide web site that contains reports, proxy statements and other information about issuers, like us, who file reports electronically with the SEC. The address of that site is http://www.sec.gov.

We have filed with the SEC a registration statement on Form S-3, which registers the securities that we may offer under this prospectus. This prospectus is part of that registration statement and, as permitted by the SEC’s rules, does not contain all the information required to be set forth in the registration statement. We believe that we have included or incorporated by reference all information material to investors in this prospectus, but some details that may be important for specific investment purposes have not been included. For further information, you should read the registration statement and the exhibits filed with or incorporated by reference into the registration statement.

 

B-2

---

Table of Contents

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to incorporate by reference information into this prospectus. This means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be part of this prospectus, except for any information that is superceded by subsequent incorporated documents or by information that is included directly in this prospectus or any prospectus supplement. We incorporate by reference the documents listed below and any future filings we make with the SEC after the date of this prospectus and until the termination of this offering under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act:

 

•

Annual Report on Form 10-K for the year ended December 31, 2007, filed March 7, 2008 (including those portions of our Proxy Statement on Schedule 14A relating to our 2008 Annual Meeting of Stockholders, which was filed on March 17, 2008, incorporated by reference therein) except Part I, Items 1 and 2, and Part II, Item 8;

 

•

Quarterly Reports on Form 10-Q for the quarter ended March 31, 2008, filed May 9, 2008; and the quarter ended June 30, 2008, filed August 7, 2008; and

 

•

Current Reports on Form 8-K filed January 11, 2008; January 25, 2008; April 2, 2008; April 24, 2008; July 9, 2008; July 11, 2008; July 24, 2008; September 12, 2008 and October 16, 2008.

Nothing in this prospectus shall be deemed to incorporate information furnished but not filed with the SEC.

You may obtain any of these incorporated documents from us without charge, excluding any exhibits to those documents unless the exhibit is specifically incorporated by reference in such document. You may obtain documents incorporated by reference in this prospectus by requesting them from us in writing or by telephone at the following address:

Columbia Banking System, Inc.

1301 “A” Street

Tacoma, Washington 98402-4200

(253) 305-1900

Attention: Cathleen Dent, Corporate Secretary

In addition, we maintain a corporate website, www.columbiabank.com. We make available through our website, our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and any amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. This reference to our website is for the convenience of investors as required by the SEC and shall not be deemed to incorporate any information on the website into this registration statement, prospectus and any prospectus supplement.

ABOUT COLUMBIA

Columbia Banking System, Inc., headquartered in Tacoma, Washington, is a regional bank holding company providing commercial banking services in Washington and Oregon, primarily along the Interstate 5 (North-South) corridor. We offer a wide range of banking products and services, including transaction and savings deposits, commercial, consumer and real estate loans, mortgage origination services, and retail brokerage services. We serve individuals, small to medium-sized businesses, community organizations and public entities.

Our wholly owned banking subsidiary, Columbia Bank, has banking offices located in the Tacoma metropolitan area and contiguous parts of the Puget Sound region of Washington State, as well as the Longview and Woodland communities in southwestern Washington State; the Bellingham community in northwestern Washington State; and in the Portland, Oregon area as well as the northern coast of Oregon.

 

B-3

---

Table of Contents

With the 2007 acquisitions of Mountain Bank Holding Company and Town Center Bancorp and the 2008 internal merger of its subsidiary, Bank of Astoria, into Columbia Bank, Columbia has 55 banking offices in Pierce, King, Cowlitz, Kitsap, Thurston and Whatcom counties in Washington State, and Clackamas, Clatsop, Tillamook and Multnomah counties in Oregon. Included in Columbia Bank are former branches of Mt. Rainier National Bank, doing business as Mt. Rainier Bank, with five branches in King and Pierce counties in Washington State. Columbia Bank does business under the Bank of Astoria name at the Bank of Astoria’s former branches located in Astoria, Warrenton, Seaside and Cannon Beach in Clatsop County and in Manzanita in Tillamook County in Oregon.

As of June 30, 2008, we had total assets of approximately $3.17 billion, total net loans receivable and loans held for sale of approximately $2.23 billion, total deposits of approximately $2.39 billion and approximately $344 million in shareholders’ equity.

USE OF PROCEEDS

Unless we specify otherwise in a prospectus supplement, we intend to use the net proceeds from our sale of the securities under this prospectus for general corporate purposes, which may include repaying indebtedness, making additions to our working capital, funding future acquisitions, or for any other purpose we describe in the applicable prospectus supplement. Until we use the proceeds for any purpose, we expect to invest them in interest bearing securities.

PLAN OF DISTRIBUTION

We may sell the securities being offered hereby to one or more underwriters for public offering and sale by them and may also sell the securities directly or through agents. We will name any underwriter or agent involved in the offer and sale of securities in the applicable prospectus supplement. We have also reserved the right to sell or exchange securities directly to investors on our own behalf in those jurisdictions where we are authorized to do so.

We may distribute the securities from time to time in one or more transactions (a) at a fixed price; (b) at market prices prevailing at the time of sale; (c) at prices related to such prevailing market prices, or (d) at negotiated prices.

We may also, from time to time, authorize dealers, acting as our agents, to offer and sell securities upon the terms and conditions set forth in the applicable prospectus supplement. In connection with the sale of securities, we, or the purchasers of securities for whom the underwriters may act as agents, may compensate the underwriters in the form of underwriting discounts or commissions. Underwriters may sell the securities to or through dealers, and those dealers may receive compensation in the form of discounts or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agent. Each prospectus supplement will indicate if an agent will be acting on a best efforts basis and a dealer will purchase securities as a principal, and resell the securities at varying prices to be determined by the dealer; or if the underwriter has undertaken to sell the securities in a firm underwritten offering.

We will describe in the applicable prospectus supplement, the specific plan of distribution, any compensation we pay to underwriters or agents in connection with the offering of securities, and any discounts, concessions or commissions allowed by underwriters to participating dealers. Dealers and agents participating in the distribution of securities may be deemed to be underwriters, and any discounts and commissions received by them and any profit realized by them on the resale of securities may be deemed to be underwriting discounts and commissions. We may enter into agreements to indemnify underwriters, dealers and agents against certain civil liabilities, including liabilities under the Securities Act of 1933 (“Securities Act”), and to reimburse them for certain expenses.

 

B-4

---

Table of Contents

To facilitate the offering of securities, certain persons participating in the offering may engage in transactions that stabilize, maintain, or otherwise affect the price of the securities. This may include over-allotments or short sales of securities, which involve the sale by persons participating in the offering of more securities than we sold to them. In these circumstances, these persons would cover such over-allotments or short positions by making purchases in the open market or by exercising their over-allotment option, if any. In addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions may be discontinued at any time.

Certain of the underwriters, dealers or agents and their associates may engage in transactions with or perform services for us in the ordinary course of their business for which they receive compensation.

DESCRIPTION OF SECURITIES

We may offer shares of common stock and preferred stock under this prospectus. Our authorized capital stock consists of:

 

•

63,032,681 shares of common stock, no par value per share; and

 

•

2,000,000 shares of preferred stock, no par value per share.

As of September 30, 2008, there were 18,146,870 shares of our common stock issued and outstanding and 224,997 shares of our common stock issuable upon exercise of outstanding stock options under our stock option plans and approximately 71,065 shares of our common stock reserved for future issuance under our stock option plans and unvested shares of restricted stock. As of September 30, 2008, there were no shares of our preferred stock issued and outstanding.

The following section describes the material features and rights of our capital stock. The summary does not purport to be exhaustive and is qualified in its entirety by reference to our Amended and Restated Articles of Incorporation (“Articles of Incorporation”), Restated and Amended Bylaws (“Bylaws”), each of which is filed as an exhibit to the registration statement of which this prospectus is a part, and to applicable Washington law.

Common Stock

The holders of our common stock have one vote per share on all matters submitted to a vote of our shareholders. There are no cumulative voting rights for the election of directors. Holders of common stock are entitled to receive ratably such dividends as may be declared by the Board of Directors out of legally available funds, subject to preferences that may be applicable to any outstanding series of preferred stock. In the event of a liquidation, dissolution or winding up of the Company, the holders of common stock are entitled to share ratably in all assets remaining after payment of liabilities and the liquidation preference of any outstanding preferred stock. Holders of shares of our common stock have no preemptive, subscription, redemption, sinking fund or conversion rights.

Dividends. The holders of our common stock are entitled to receive dividends declared by our Board of Directors out of funds legally available therefor. Holders of preferred stock and debt securities, however, have a priority right to distributions and payment over our common stock. Our ability to pay dividends basically depends on the amount of dividends paid to us by our subsidiaries. The payment of dividends is subject to government regulation, in that regulatory authorities may prohibit banks and bank holding companies from paying dividends in a manner that would constitute an unsafe or unsound banking practice. In addition, a bank may not pay cash dividends if doing so would reduce the amount of its capital below that necessary to meet minimum regulatory capital requirements. State laws also limit a bank’s ability to pay dividends. Accordingly,

 

B-5

---

Table of Contents

the dividend restrictions imposed on our subsidiaries by statute or regulation effectively may limit the amount of dividends we can pay.

The transfer agent and registrar for our common stock is American Stock Transfer & Trust Co.

Preferred Stock

Under our Articles of Incorporation, our Board of Directors has the authority to issue 2,000,000 shares of preferred stock in one or more series and to fix, determine or amend the relative rights and preferences of the shares of any series so established, within the limitations set forth in the Washington Business Corporation Act (“WBCA”), relating to the powers, designations, rights, preferences, and restrictions thereof, including, but not limited to:

 

•

dividend rights

 

•

conversion rights,

 

•

voting rights,

 

•

redemption terms,

 

•

liquidation preferences, and

 

•

the number of shares constituting each such series, without any further vote or action by our shareholders.

Antitakeover Effects of Certain Provisions in our Articles, Bylaws and Washington Law

Some provisions of our Articles of Incorporation, our Bylaws, and Washington law may be deemed to have an antitakeover effect and may collectively operate to delay, defer or prevent a tender offer or takeover attempt that a shareholder might consider in his or her best interest, including those attempts that might result in a premium over the market price for the shares held by our shareholders. These provisions include:

Preferred Stock Authorization. As noted above, our Board of Directors, without shareholder approval, has the authority under our Articles of Incorporation to issue preferred stock with rights superior to the rights of the holders of common stock. As a result, preferred stock, while not intended as a defensive measure against takeovers, could be issued quickly and easily, could adversely affect the rights of holders of common stock and could be issued with terms calculated to delay or prevent a change of control of Columbia or make removal of management more difficult.

Articles of Incorporation Limitation on Business Combinations. Columbia’s Articles of Incorporation include certain provisions that could make more difficult the acquisition of Columbia by means of a tender offer, a proxy contest, merger or otherwise. These provisions include:(a) certain non-monetary factors that the Columbia Board of Directors may consider when evaluating a takeover offer, as described below, and (b) a requirement that any “Business Combination” (as defined in the Articles of Incorporation) be approved by the affirmative vote of no less than 66 ²/3% of the total shares attributable to persons other than a “Control Person” (as defined in the Articles of Incorporation), unless certain conditions are met.

Columbia’s Articles of Incorporation allow the Columbia Board of Directors to consider non-monetary factors in evaluating certain takeover bids. Specifically, the Articles of Incorporation allow the Board of Directors, in determining what is in the best interests of Columbia and its shareholders, to consider all relevant factors, including, without limitation, the social and economic effects on its employees, customers, suppliers and other constituents of Columbia and its subsidiaries and on the communities in which Columbia and its subsidiaries operate or are located.

 

B-6

---

Table of Contents

The requirement for “Super-Majority” approval of certain business transactions does not apply if the Columbia Board of Directors has approved the transaction or if certain other conditions concerning non discrimination among shareholders, receipt of fair value and the mailing of a proxy statement responsive to the requirements of the Exchange Act to Columbia’s public shareholders, are satisfied.

The matters described above may have the effect of lengthening the time required for a person to acquire control of Columbia through a tender offer, proxy contest, or otherwise, and may deter any potentially unfriendly offers or other efforts to obtain control of Columbia. This could deprive Columbia’s shareholders of opportunities to realize a premium for their Columbia stock, even in circumstances where such action was favored by a majority of Columbia shareholders.

In addition to the provisions contained in Columbia’s Articles of Incorporation, Washington law also requires prior approval by a majority of the board of directors of a target company in certain acquisition transactions. Washington law prohibits corporations that have a class of voting stock registered under the Exchange Act, such as Columbia, from engaging in any “Significant Business Transaction” (defined to include mergers or consolidations, certain sales, termination of 5% or more of a corporation’s employees, sales of assets, liquidation or dissolution, and other specified transactions) for a period of five years after a person or group acquires 10% or more of a corporation’s outstanding voting stock, unless the acquisition is approved in advance by a majority vote of the board of directors, or, at or subsequent to the acquiring person or group’s acquisition of shares of the corporation, such Significant Business Transaction is approved by a majority vote of the target corporation’s board of directors and authorized by the affirmative vote of at least two-thirds of the corporation’s outstanding voting shares (except those beneficially owned or under voting control of the acquiring person).

Amendment of Articles of Incorporation and Bylaws. Under the WBCA, the Articles of Incorporation of Columbia, as a “public” company, may be amended upon the affirmative vote of the holders of a majority of Columbia’s outstanding voting stock. However, the provisions of Article 9 of Columbia’s Articles of Incorporation, relating to Business Combinations (as defined in the Articles of Incorporation), may not be amended or repealed without the affirmative vote of 66 ²/3% of Columbia’s outstanding voting stock. The Columbia Board of Directors may make certain amendments, as listed in the WBCA, to the Articles of Incorporation without shareholder approval. The Columbia Board of Directors may, by a majority vote, amend or repeal Columbia’s Bylaws.

 

B-7

---

Table of Contents

LEGAL MATTERS

Unless otherwise specified in the applicable prospectus supplement, the validity of the securities will be passed upon for us by Graham & Dunn PC, and will be passed upon for any agents, dealers or underwriters by counsel named in the applicable prospectus supplement.

EXPERTS

The consolidated financial statements incorporated in this Prospectus by reference from the Company’s Current Report on Form 8-K dated October 15, 2008, and the effectiveness of the Company’s internal control over financial reporting incorporated in this Prospectus by reference from the Company’s Annual Report on Form 10-K as of December 31, 2007, have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports, which are incorporated herein by reference. Such financial statements have been so incorporated in reliance upon the reports of such firm given upon their authority as experts in accounting and auditing.

 

B-8

---

Table of Contents

---

Table of Contents