ZION 10-K Fiscal year ended Dec. 31, 2010

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

For the fiscal year ended December 31, 2010

OR

For the transition period from              to

COMMISSION FILE NUMBER 001-12307

ZIONS BANCORPORATION

(Exact name of Registrant as specified in its charter)

Registrant’s telephone number, including area code: (801) 524-4787

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None.

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes x No ¨

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes ¨ No x

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes x No ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes x No ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (Section 229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer,” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer x Accelerated filer ¨ Non-accelerated filer ¨ Smaller reporting company ¨

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ¨ No x

Documents Incorporated by Reference:

Portions of the Company’s Proxy Statement – Incorporated into Part III

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FORM 10-K TABLE OF CONTENTS

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FORWARD-LOOKING INFORMATION

Statements in this Annual Report on Form 10-K that are based on other than historical data are forward-looking within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements provide current expectations or forecasts of future events and include, among others:

These forward-looking statements are not guarantees of future performance, nor should they be relied upon as representing management’s views as of any subsequent date. Forward-looking statements involve significant risks and uncertainties and actual results may differ materially from those presented, either expressed or implied, including, but not limited to, those presented in the Management’s Discussion and Analysis. Factors that might cause such differences include, but are not limited to:

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Except to the extent required by law, the Company specifically disclaims any obligation to update any factors or to publicly announce the result of revisions to any of the forward-looking statements included herein to reflect future events or developments.

AVAILABILITY OF INFORMATION

We also make available free of charge on our website, www.zionsbancorporation.com , annual reports on Form 10-K, quarterly reports on Form 10-Q, and current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as well as proxy statements, as soon as reasonably practicable after we electronically file such material with, or furnish it to, the U.S. Securities and Exchange Commission.

GLOSSARY OF ACRONYMS

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DESCRIPTION OF BUSINESS

Zions Bancorporation (“the Parent”) is a financial holding company organized under the laws of the State of Utah in 1955, and registered under the Bank Holding Company Act of 1956, as amended (the “BHC Act”). The Parent and its subsidiaries (collectively “the Company”) own and operate eight commercial banks with a total of 495 domestic branches at year-end 2010. The Company provides a full range of banking and related services through its banking and other subsidiaries, primarily in Utah, California, Texas, Arizona, Nevada, Colorado, Idaho, Washington, and Oregon. Full-time equivalent employees totaled 10,524 at year-end 2010. For further information about the Company’s industry segments, see “Business Segment Results” on page 46 in MD&A and Note 22 of the Notes to Consolidated Financial Statements. For information about the Company’s foreign operations, see “Foreign Operations” on page 46 in MD&A. The “Executive Summary” on page 23 in MD&A provides further information about the Company.

PRODUCTS AND SERVICES

The Company focuses on providing community banking services by continuously strengthening its core business lines of 1) small and medium-sized business and corporate banking; 2) commercial and residential development, construction and term lending; 3) retail banking; 4) treasury cash management and related products and services; 5) residential mortgage; 6) trust and wealth management; and 7) investment activities. It operates eight different banks in ten Western and Southwestern states with each bank operating under a different name and each having its own board of directors, chief executive officer, and management team. The banks provide a wide variety of commercial and retail banking and mortgage lending products and services. They also provide a wide range of personal banking services to individuals, including home mortgages, bankcard, other installment loans, home equity lines of credit, checking accounts, savings accounts, time certificates of deposits of various types and maturities, trust services, safe deposit facilities, direct deposit, and 24-hour ATM access. In addition, certain banking subsidiaries provide services to key market segments through their Women’s Financial, Private Client Services, and Executive Banking Groups. We also offer wealth management services through a subsidiary, Contango, and online brokerage services through Zions Direct.

In addition to these core businesses, the Company has built specialized lines of business in capital markets and public finance, and is a leader in SBA lending. Through its eight banking subsidiaries, the Company provides SBA 7(a) loans to small businesses throughout the United States and is also one of the largest providers of SBA 504 financing in the nation. The Company owns an equity interest in the Farmer Mac and is one of the nation’s top originators of secondary market agricultural real estate mortgage loans through Farmer Mac. The Company is a leader in municipal finance advisory and underwriting services.

COMPETITION

The Company operates in a highly competitive environment. The Company’s most direct competition for loans and deposits comes from other commercial banks, thrifts, and credit unions, including institutions that do not have a physical presence in our market footprint but solicit via the Internet and other means. In addition, the Company competes with finance companies, mutual funds, brokerage firms, securities dealers, investment banking companies, and a variety of other types of companies. Many of these companies have fewer regulatory constraints and some have lower cost structures or tax burdens.

The primary factors in competing for business include pricing, convenience of office locations and other delivery methods, range of products offered, and the level of service delivered. The Company must compete effectively along all of these parameters to remain successful.

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SUPERVISION AND REGULATION

The banking and financial services business in which we engage is highly regulated. Such regulation is intended, among other things, to improve the stability of banking and financial companies and to protect the interests of customers, including depositors. These regulations are not, however, generally charged with protecting the interests of our shareholders or creditors. Described below are the material elements of selected laws and regulations applicable to the Company. The descriptions are not intended to be complete and are qualified in their entirety by reference to the full text of the statutes and regulations described. Changes in applicable law or regulations, and in their application by regulatory agencies, cannot be predicted, but they may have a material effect on the business and results of the Company.

The Parent is a bank holding company and a financial holding company as provided by the GLB. The BHC Act, and other federal statutes as modified by the GLB Act and the Dodd-Frank Act, provide the regulatory framework for bank holding companies and financial holding companies which have as their umbrella regulator the Federal Reserve Board. The functional regulation of the separately regulated subsidiaries of a bank holding company is conducted by each subsidiary’s primary functional regulator. To qualify for and maintain status as a financial holding company, the Parent and its subsidiary banks must satisfy certain ongoing criteria. The Company currently engages in only limited activities for which financial holding company status is required.

The Parent’s subsidiary banks are subject to the provisions of the National Bank Act or other statutes governing national banks and the banking laws of their various states, as well as the rules and regulations of the OCC, the FRB, and the FDIC. They are also under the supervision of, and are continually subject to periodic examination by, the OCC or their respective state banking departments, the FRB, and the FDIC. Many of our nonbank subsidiaries are also subject to regulation by the FRB and other applicable federal and state agencies. Our brokerage and investment advisory subsidiaries are regulated by the SEC, FINRA and/or state securities regulators.

The Dodd-Frank Act

The events of the past few years have led to numerous new laws in the United States and internationally for financial institutions. The Dodd-Frank Wall Street Reform and Consumer Protection Act (the “Dodd-Frank Act” or “Dodd-Frank”), which was enacted in July 2010, is one of the most far reaching legislative actions affecting the financial services industry in decades and significantly restructures the financial regulatory regime in the United States. Among other major things, it creates a new systemic risk oversight body, the FSOC. The FSOC will oversee and coordinate the efforts of the primary U.S. financial regulatory agencies (including the FRB, the SEC, the Commodity Futures Trading Commission and the FDIC) in establishing regulations to address financial stability concerns. The Dodd-Frank Act directs the FSOC to make recommendations to the FRB as to supervisory requirements and heightened prudential standards applicable to large bank holding companies, such as Zions, including capital, leverage, liquidity and risk-management requirements.

In addition, the Dodd-Frank Act broadly affects the financial services industry by creating a resolution authority, mandating higher capital and liquidity requirements and requiring banks to pay increased fees to regulatory agencies, and through numerous other provisions aimed at strengthening the sound operation of the financial services sector. Among other things affecting capital standards, the Dodd-Frank Act provides that:

These provisions will require us to maintain greater levels of capital and will limit the forms of capital that we will be able to rely upon for regulatory purposes. For example, provisions of the Dodd-Frank Act require us

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to deduct, over three years beginning July 21, 2011, all trust preferred securities from our Tier 1 capital. Some of the Act’s provisions affecting the fees we must pay to regulatory agencies and pricing of our products and services include:

The Dodd-Frank Act also creates a new CFPB, which will be responsible for promulgating regulations designed to protect consumers’ financial interests and examining financial institutions for compliance with, and enforcing, those regulations. The Dodd-Frank Act will subject national banks to further regulation by restricting the preemption of state laws by federal laws, which currently enables national banks and their subsidiaries to comply with federal regulatory requirements without complying with various state laws. In addition, the Act gives greater power to state attorneys general to pursue legal actions against banking organizations for violations of federal law.

As discussed further throughout this section, many aspects of Dodd-Frank are subject to further rulemaking and will take effect over several years, making it difficult to anticipate the overall financial impact on the Company or across the industry.

Capital Standards – Basel Framework

The FRB has established capital guidelines for financial holding companies. The OCC, the FDIC, and the FRB have also issued regulations establishing capital requirements for banks. These bank regulatory agencies’ risk-based capital guidelines are based upon the 1988 capital accord (“Basel I”) of the Basel Committee on Banking Supervision (the “BCBS”). The BCBS is a committee of central banks and bank supervisors/regulators from the major industrialized countries that develops broad policy guidelines that each country’s supervisors can use to determine the supervisory policies they apply.

In 2004, the BCBS proposed a new capital accord (“Basel II”) to replace Basel I. Basel II provides two approaches for setting capital standards for credit risk – an advanced internal ratings-based approach tailored to individual institutions’ circumstances and a standardized approach that bases risk weightings on external credit assessments to a much greater extent than permitted in existing guidelines. Basel II also sets capital requirements for operational risk and refines the existing capital requirements for market risk exposures.

In December 2007, U.S. banking regulators published the final rule for Basel II implementation, requiring banks with over $250 billion in consolidated total assets or on-balance sheet foreign exposure of $10 billion (core banks) to adopt the advanced approaches of Basel II while allowing other banks to elect to “opt in.” The Parent is not required to comply with the Basel II. In July 2008, the agencies issued a proposed rule that would give banking organizations that do not use the advanced approaches the option to implement a new risk-based capital framework which would adopt the standardized approach of Basel II for credit risk, the basic indicator approach of Basel II for operational risk and related disclosure requirements. A definitive rule has not been issued.

In December 2010, the BCBS released its final framework for strengthening international capital and liquidity regulation, now officially identified by the BCBS as “Basel III”. Basel III, when implemented by the

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U.S. banking agencies and fully phased-in, will require bank holding companies and their bank subsidiaries to maintain substantially more capital, with a greater emphasis on common equity. The Basel III final capital framework, among other things:

The capital conservation buffer is designed to absorb losses during periods of economic stress. Banking institutions with a ratio of CET1 to risk-weighted assets above the minimum but below the conservation buffer (or below the combined capital conservation buffer and countercyclical capital buffer, when the latter is applied) will face constraints on dividends, equity repurchases and compensation based on the amount of the short fall.

The implementation of the Basel III final framework is expected to commence January 1, 2013. On that date, banking institutions will be required to meet the following minimum capital ratios:

The Basel III final framework provides for a number of new deductions from and adjustments to CET1. These include, for example, the requirement that mortgage servicing rights, deferred tax assets dependent upon future taxable income and significant investments in non-consolidated financial entities be deducted from CET1 to the extent that any one such category exceeds 10% of CET1 or all such categories in the aggregate exceed 15% of CET1. Implementation of the deductions and other adjustments to CET1 will begin on January 1, 2014 and will be phased-in over a five-year period (20% per year). The implementation of the capital conservation buffer will begin on January 1, 2016 at 0.625% and will be phased in over a four-year period (increasing by that amount on each subsequent January 1, until it reaches 2.5% on January 1, 2019).

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The U.S. banking agencies have indicated informally that they expect to propose regulations implementing Basel III in mid-2011 with final adoption of implementing regulations in mid-2012. Given that the Basel III rules are subject to change, and the scope and content of capital regulations that the U.S. banking agencies may adopt under Dodd-Frank is uncertain, we cannot be certain of the impact new capital regulations will have on our capital ratios.

Historically, regulation and monitoring of bank and bank holding company liquidity has been addressed as a supervisory matter, both in the U.S. and internationally, without required formulaic measures. The Basel III framework proposes that banks and bank holding companies measure their liquidity against specific liquidity tests that, although similar in some respects to liquidity measures historically applied by banks and regulators for management and supervisory purposes, going forward will be required by regulation. One proposed test, referred to as the LCR, would be designed to ensure that the banking entity maintains an adequate level of unencumbered high-quality liquid assets equal to the entity’s expected net cash outflow for a 30-day time horizon (or, if greater, 25% of its expected total cash outflow) under an acute liquidity stress scenario. The other measure, referred to as the NSFR, would be designed to promote more medium- and long-term funding of the assets and activities of banking entities over a one-year time horizon. These requirements will incent banking entities to increase their holdings of U.S. Treasury securities and other sovereign debt as a component of assets and increase the use of long-term debt as a funding source. The LCR would be implemented subject to an observation period beginning in 2011, but would not be introduced as a requirement until January 1, 2015, and the NSFR would not be introduced as a requirement until January 1, 2018. These new standards are subject to further rulemaking and their terms may well change before implementation.

Other Regulation

The Company is subject to a wide range of other requirements and restrictions contained in both the laws of the United States and the states in which its banks and other subsidiaries operate. These regulations include but are not limited to the following:

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The Parent is subject to the disclosure and regulatory requirements of the Securities Act of 1933, as amended, and the Securities Exchange Act of 1934, as amended, both as administered by the SEC. As a company listed on the NASDAQ Global Select Market, the Parent is subject to NASDAQ listing standards for quoted companies.

The Company is subject to the Sarbanes-Oxley Act of 2002, which addresses, among other issues, corporate governance, auditing and accounting, executive compensation, and enhanced and timely disclosure of corporate information. Nasdaq has also adopted corporate governance rules, which are intended to allow shareholders and investors to more easily and efficiently monitor the performance of companies and their directors.

The Board of Directors of the Parent has implemented a comprehensive system of corporate governance practices. This system includes Corporate Governance Guidelines, a Code of Business Conduct and Ethics for Employees, a Directors Code of Conduct, and charters for the Audit, Credit Review, Compensation, and Nominating and Corporate Governance Committees. More information on the Company’s corporate governance practices is available on the Company’s website at www.zionsbancorporation.com . (The Company’s website is not part of this Annual Report on Form 10-K.)

The Company has adopted policies, procedures and controls to address compliance with the requirements of the banking, securities and other laws and regulations described above or otherwise applicable to the Company. The Company intends to make appropriate revisions to reflect any changes required.

Regulators, Congress, state legislatures and international consultative bodies continue to enact rules, laws, and policies to regulate the financial services industry and public companies and to protect consumers and investors. The nature of these laws and regulations and the effect of such policies on future business and earnings of the Company cannot be predicted.

GOVERNMENT MONETARY POLICIES

The earnings and business of the Company are affected not only by general economic conditions, but also by policies adopted by various governmental authorities. The Company is particularly affected by the monetary policies of the FRB, which affect both short-term and long-term interest rates and the national supply of bank credit. The tools available to the FRB which may be used to implement monetary policy include:

These methods are used in varying combinations to influence the overall growth or contraction of bank loans, investments and deposits, and the interest rates charged on loans or paid for deposits.

In view of the changing conditions in the economy and the effect of the FRB’s monetary policies, it is difficult to predict future changes in loan demand, deposit levels and interest rates, or their effect on the business and earnings of the Company. FRB monetary policies have had a significant effect on the operating results of commercial banks in the past and are expected to continue to do so in the future.

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The following list describes several risk factors which are significant to the Company including but not limited to:

The Company has been and could continue to be negatively affected by adverse economic conditions.

The United States and many other countries recently faced a severe economic crisis, including a major recession. These adverse economic conditions have negatively affected, and are likely to continue for some time to adversely affect, the Company’s assets, including its loans and securities portfolios, capital levels, results of operations, and financial condition. In response to the economic crisis, the United States and other governments established a variety of programs and policies designed to mitigate the effects of the crisis. These programs and policies appear to have stabilized the severe financial crisis that occurred in the second half of 2008, but the extent to which these programs and policies will assist in an economic recovery or may lead to adverse consequences, whether anticipated or unanticipated, is still unclear. If these programs and policies are ineffective in bringing about an economic recovery or result in substantial adverse developments, the economic conditions may again become more severe, or adverse economic conditions may continue for a substantial period of time. Any increase in the severity or duration of adverse economic conditions, including a double dip recession or delay in the recovery, would adversely affect the Company.

The limitations on incentive compensation contained in the ARRA, the implementing of its regulations, and other bank regulations may adversely affect our ability to retain our highest performing employees.

Because we have not yet repurchased the U.S. Treasury’s CPP investment, we remain subject to the restrictions on incentive compensation contained in the ARRA. On June 10, 2009, the U.S. Treasury released its interim final rules implementing the provisions of the ARRA and limiting the compensation practices at institutions in which the U.S. Treasury is invested. The U.S. Treasury has since revised such rules and released written guidance interpreting and expanding on ARRA and the interim final rules. Financial institutions which have repurchased the U.S. Treasury’s CPP investment are relieved of the restrictions imposed by the ARRA and its implementing regulations and related guidance. Due to these restrictions, we may not be able to successfully compete with financial institutions that have repurchased the U.S. Treasury’s investment to attract, retain and appropriately incentivize high performing employees. In addition, bank regulatory agencies have published guidance and proposed regulations which limit the manner and amount of compensation that banking organizations provide to employees. These regulations and guidance may adversely affect our ability to retain key personnel. If we were to suffer such adverse effects with respect to our employees, our business, financial condition and results of operations could be adversely affected, perhaps materially.

Our participation in the CPP and other government programs imposes restrictions and obligations on us that limit our ability to increase dividends, repurchase shares of our stock, and access the equity capital markets.

The Company has chosen to participate in a number of new programs sponsored by the U.S. Government during the current financial and economic crisis. These programs, including without limitation, the TARP and its associated CPP, as well as the ARRA and EESA and regulations thereunder, contain important limitations on the Company’s conduct of its business, including limitations on dividends, repurchases of common stock, acquisitions, and executive compensation. These limitations may adversely impact the Company’s ability to attract nongovernmental capital and to recruit and retain executive management and other personnel and its ability to compete with other American and foreign financial institutions. One of these programs, the CPP, contains provisions that allow the U.S. Government to unilaterally modify any term or provision of contracts executed under the program.

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Recently adopted financial reform legislation will impose significant new limitations on our business activities and subject us to increased regulation and additional costs.

The Dodd-Frank Wall Street Reform and Consumer Protection Act enacted on July 21, 2010 will have material implications for the Company and the entire financial services industry. The Act results in the Company being defined as “systemically important,” which brings significant additional regulatory oversight and requirements. In addition, among other things, the Act will or potentially could:

As the Act requires that many studies be conducted and that hundreds of regulations be written in order to fully implement it, the full impact of this legislation on the Company, its business strategies, and financial performance cannot be known at this time, and may not be known for a number of years. In addition, the current political environment may lead, in the near future, to the adoption of new laws and regulations affecting financial institutions.

U.S. regulatory agencies, in response to the adoption of Basel III, may require us to raise our capital and liquidity to levels that may exceed those that the market may otherwise consider to be optimal.

Basel III was adopted in December 2010 by the BCBS. New capital and liquidity requirements are expected to be established by U.S. regulatory agencies in response to Basel III which are higher than previous levels. Maintaining higher capital and liquidity levels may reduce our profitability and performance measures.

Economic and other circumstances, including pressure to repay CPP preferred stock, may require us to raise capital at times or in amounts that are unfavorable to the Company.

The Company’s subsidiary banks must maintain certain risk-based and leverage capital ratios as required by their banking regulators which can change depending upon general economic conditions and their particular condition, risk profile and growth plans. Compliance with capital requirements may limit the Company’s ability to expand and has required, and may require, capital investment from the Parent. In 2008, we issued shares of preferred stock and a warrant to purchase shares of the Company’s common stock to the U.S. Treasury for $1.4 billion under TARP. There may be increasing market, regulatory or political pressure on the

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Company to raise capital to enable it to repay the preferred stock issued to the U.S. Treasury under TARP at a time or in amounts that may be unfavorable to the Company’s shareholders. These uncertainties and risks created by the legislative and regulatory uncertainties discussed above may themselves increase the Company’s cost of capital and other financing costs.

Negative perceptions associated with our continued participation in the U.S. Treasury’s CPP may adversely affect our ability to retain customers, attract investors, and compete for new business opportunities.

Several financial institutions which also participated in the CPP have repurchased their TARP preferred stock. There can be no assurance as to the timing or manner in which the Company may repurchase its Series D Preferred Stock from the U.S. Treasury. Our customers, employees and counterparties in our current and future business relationships could draw negative implications regarding the strength of the Company as a financial institution based on our continued participation in the CPP following the exit of one or more of our competitors or other financial institutions. Any such negative perceptions could impair our ability to effectively compete with other financial institutions for business or to retain high performing employees. If this were to occur, our business, financial condition, and results of operations may be adversely affected.

Credit quality has adversely affected us and may continue to adversely affect us.

Credit risk is one of our most significant risks. The Company’s credit quality continued at a weakened level during 2010 in most loan types and markets in which the Company operates. Although most credit quality indicators improved during latter half of 2010, we expect continued credit quality weakness over the next few quarters.

Weakness in the economy and in the real estate market, including specific weakness within the markets where our subsidiary banks do business and within certain of our loan products, has adversely affected us and may continue to adversely affect us.

Our credit exposure is one of our most significant risks. The company’s level of problem credits remained high as of December 31, 2010. The deterioration in credit quality that started in the latter half of 2007 has most significantly affected the construction and land development segment of our portfolio. Although virtually all of our markets and lending segments have been adversely affected by the economic recession, the distress has been mostly concentrated in construction and land development loans in the Southwest states (generally, Arizona, California, and Nevada), which markets have been particularly adversely affected by job losses, declines in residential and commercial sale volumes and real estate values, and declines in new construction activity.

Subsequent to the initial deterioration in construction and land development loans, credit quality deterioration occurred in most loan types and geographies in which the Company operated through the first half of 2010 as general economic conditions weakened throughout the country.

If the strength of the U.S. economy in general and the strength of the local economies in which we and our subsidiary banks conduct operations decline further, this could result in, among other things, further deterioration in credit quality and/or continued reduced demand for credit, including a resultant adverse effect on the income from our loan portfolio, an increase in charge-offs and an increase in the allowance for loan and lease losses; if such developments occur, we may be required to raise additional capital.

Failure to effectively manage our interest rate risk could adversely affect us.

Net interest income is the largest component of the Company’s revenue. The management of interest rate risk for the Company and all bank subsidiaries is centralized and overseen by an Asset Liability Management Committee appointed by the Company’s Board of Directors. We have been successful in our interest rate risk

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management as evidenced by achieving a relatively stable net interest margin over the last several years when interest rates have been volatile and the rate environment challenging; however, a failure to effectively manage our interest rate risk could adversely affect us. Factors beyond the Company’s control can significantly influence the interest rate environment and increase the Company’s risk. These factors include competitive pricing pressures for our loans and deposits, adverse shifts in the mix of deposits and other funding sources, and volatile market interest rates subject to general economic conditions and the policies of governmental and regulatory agencies, in particular the FRB.

Our ability to maintain required capital levels and adequate sources of funding and liquidity has been and may continue to be adversely affected by market conditions.

We are required to maintain certain capital levels in accordance with banking regulations and any capital requirements imposed by our regulators. We must also maintain adequate funding sources in the normal course of business to support our operations and fund outstanding liabilities. Our ability to maintain capital levels, sources of funding, and liquidity has been and could continue to be impacted by changes in the capital markets in which we operate and deteriorating economic and market conditions.

Each of our subsidiary banks must remain well-capitalized and meet certain other requirements for us to retain our status as a financial holding company. Failure to comply with those requirements could result in a loss of our financial holding company status if such conditions are not corrected within 180 days or such longer period as may be permitted by the Federal Reserve, although we do not believe that the loss of such status would have an appreciable effect on our operations or financial results. In addition, failure by our bank subsidiaries to meet applicable capital guidelines or to satisfy certain other regulatory requirements can result in certain activity restrictions or a variety of enforcement remedies available to the federal regulatory authorities that include limitations on the ability to pay dividends, the issuance by the regulatory authority of a capital directive to increase capital and the termination of deposit insurance by the FDIC.

Funding availability improved during 2010 as compared to 2009, as the Company took a number of actions during the year to augment its capital and liquidity. More emphasis was placed upon low-cost funding during 2010 than merely funding availability (See “Capital Management” on page 84 in MD&A and Notes 12 and 13 of the Notes to Consolidated Financial Statements for further information on funding availability). However, because liquidity stresses are often a consequence of the materialization of other risks, they will continue to be a risk factor in 2011 and beyond for the Company, the Parent and its affiliate banks.

The quality and liquidity of our asset-backed investment securities portfolio has adversely affected us and may continue to adversely affect us.

The Company’s asset-backed investment securities portfolio includes CDOs collateralized by trust preferred securities issued by banks, insurance companies, and REITs that may have some exposure to construction loan, commercial real estate, and the subprime markets and/or to other categories of distressed assets. In addition, asset-backed securities also include structured asset-backed CDOs (also known as diversified structured finance CDOs) which have exposure to subprime and home equity mortgage securitizations. Factors beyond the Company’s control can significantly influence the fair value and impairment status of these securities. These factors include, but are not limited to, defaults, deferrals, and restructurings by debt issuers, rating agency downgrades of securities, lack of market pricing of securities, or the return of market pricing that varies from the Company’s current model valuations, and changes in prepayment rates and future interest rates. See “Investment Securities Portfolio” on page 52 for further details.

We have been unprofitable and may continue to be unprofitable, and such lack of profitability could have particular adverse effects on us, such as restricting our ability to pay dividends or requiring a valuation allowance against our deferred tax asset.

We are a holding company that conducts substantially all of its operations through its banking and other subsidiaries. As a result, our ability to make dividend payments on our common stock will depend primarily

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upon the receipt of dividends and other distributions from our subsidiaries. We and certain of our subsidiaries have been unprofitable during the last three annual reporting periods. During 2009 and 2010, the noncash accelerated amortization expense caused by subordinated debt holders converting their debt to preferred stock has contributed to our unprofitability. Future conversions of subordinated debt into preferred stock may continue to contribute to unprofitability. The ability of the Company and our subsidiary banks to pay dividends is restricted by regulatory requirements, including profitability and the need to maintain required levels of capital. Continuing lack of profitability exposes us to the risk that regulators could restrict the ability of our subsidiary banks to pay dividends and our ability to declare and pay dividends on our common stock, preferred stock or trust preferred securities. It also increases the risk that the Company may have to establish a “valuation allowance” against its net DTA. The Parent and some of its subsidiary banks already have some disallowed DTA for regulatory capital purposes.

We and/or the holders of our securities could be adversely affected by unfavorable rating actions from rating agencies.

Our ability to access the capital markets is important to our overall funding profile. This access is affected by the ratings assigned by rating agencies to us, certain of our affiliates, and particular classes of securities that we and our affiliates issue. The interest rates that we pay on our securities are also influenced by, among other things, the credit ratings that we, our affiliates, and/or our securities receive from recognized rating agencies. In the past, rating agencies have downgraded our credit ratings. Further downgrades to us, our affiliates, or our securities could increase our costs or otherwise have a negative effect on our results of operations or financial condition or the market prices of our securities.

We could be adversely affected by accounting, financial reporting, and regulatory and compliance risk.

The Company is exposed to accounting, financial reporting, and regulatory/compliance risk. The Company provides to its customers, and uses for its own capital, funding and risk management needs, a number of complex financial products and services. Estimates, judgments and interpretations of complex and changing accounting and regulatory policies are required in order to provide and account for these products and services. Identification, interpretation and implementation of complex and changing accounting standards as well as compliance with regulatory requirements, therefore pose an ongoing risk.

We could be adversely affected by legal and governmental proceedings.

The Company is subject to risks associated with legal claims, fines, litigation, and regulatory proceedings. The Company’s exposure to these proceedings has increased and may further increase as a result of stresses on customers, counterparties and others arising from the current economic environment; new regulations promulgated under recently adopted statutes; and the creation of new examination and enforcement bodies.

We could be adversely affected by failure in our internal controls.

A failure in our internal controls could have a significant negative impact not only on our earnings, but also on the perception that customers, regulators and investors may have of the Company. We continue to devote a significant amount of effort, time and resources to improving our controls and ensuring compliance with complex accounting standards and regulations.

We could be adversely affected as a result of acquisitions.

From time to time the Company makes acquisitions including the acquisition of assets and liabilities of failed banks from the FDIC acting as a receiver. The FDIC-supported transactions are subject to loan loss sharing agreements. Failure to comply with the terms of the agreements could result in the loss of indemnification from the FDIC. The success of any acquisition depends, in part, on our ability to realize the projected cost

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savings from the acquisition and on the continued growth and profitability of the acquisition target. We have been successful with most prior acquisitions, but it is possible that the merger integration process with an acquired company could result in the loss of key employees, disruptions in controls, procedures and policies, or other factors that could affect our ability to realize the projected savings and successfully retain and grow the target’s customer base.

The Company’s Board of Directors has established an Enterprise Risk Management policy and has appointed an Enterprise Risk Management Committee to oversee and implement the policy. In addition to credit and interest rate risk, the Committee also monitors the following risk areas: market risk, liquidity risk, operational risk, compliance risk, information technology risk, strategic risk, compensation-related risk, and reputation risk.

There are no unresolved written comments that were received from the SEC’s staff 180 days or more before the end of the Company’s fiscal year relating to our periodic or current reports filed under the Securities Exchange Act of 1934.

At December 31, 2010, the Company operated 495 domestic branches, of which 287 are owned and 208 are leased. The Company also leases its headquarters offices in Salt Lake City, Utah. Other operations facilities are either owned or leased. The annual rentals under long-term leases for leased premises are determined under various formulas and factors, including operating costs, maintenance, and taxes. For additional information regarding leases and rental payments, see Note 18 of the Notes to Consolidated Financial Statements.

The information contained in Note 18 of the Notes to Consolidated Financial Statements is incorporated by reference herein.

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MARKET INFORMATION

The Company’s common stock is traded on the Nasdaq Global Select Market under the symbol “ZION.” The last reported sale price of the common stock on Nasdaq on February 16, 2011 was $24.63 per share.

The following table sets forth, for the periods indicated, the high and low sale prices of the Company’s common stock, as quoted on Nasdaq:

During 2010 the Company issued $633.3 million of new common stock consisting of 29.6 million shares at an average price of $21.43 per share. Net of commissions and fees, the issuances added $623.5 million to common stock. We also issued 29.3 million common stock warrants during 2010 adding $214.6 million to common stock. Each and all of the warrants can be exercised for a share of common stock at an initial price of $36.63 through May 22, 2020. See Note 14 of the Notes to Consolidated Financial Statements for further information regarding equity transactions during 2010.

As of February 16, 2011, there were 6,068 holders of record of the Company’s common stock.

EQUITY CAPITAL AND DIVIDENDS

We have 4,400,000 authorized shares of preferred stock without par value and with a liquidation preference of $1,000 per share. As of December 31, 2010, 59,440, 453,237, 1,400,000, and 142,500 of preferred shares series A, C, D and E, respectively, have been issued and are outstanding. In addition, holders of $0.8 billion of the Company’s subordinated debt have the right to convert that debt into either Series A or C preferred stock. In general, preferred shareholders may receive asset distributions before common shareholders; however, preferred shareholders have only limited voting rights generally with respect to certain provisions of the preferred stock, the issuance of senior preferred stock, and the election of directors. Preferred stock dividends reduce earnings available to common shareholders and are paid quarterly in arrears. The redemption amount is computed at the per share liquidation preference plus any declared but unpaid dividends. The series A, C, and E shares are registered with the SEC. The Series D Fixed-Rate Cumulative Perpetual Preferred Stock was issued on November 14, 2008 to the U.S. Department of the Treasury for $1.4 billion in a private placement exempt from registration. See Note 14 of the Notes to Consolidated Financial Statements for further information regarding the Company’s preferred stock.

The frequency and amount of common stock dividends paid during the last two years are as follows:

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The Company’s Board of Directors approved a dividend of $0.01 per common share payable on February 28, 2011 to shareholders of record on February 22, 2011. The Company expects to continue its policy of paying regular cash dividends on a quarterly basis, although there is no assurance as to future dividends because they depend on future earnings, capital requirements, and financial condition.

The Company cannot increase the common stock dividend above $0.32 per share without the consent of the U.S. Treasury until the third anniversary of the date of the investment, or November 14, 2011, unless prior to such third anniversary the senior preferred stock series D is redeemed in whole or the U.S. Treasury has transferred all of the senior preferred stock series D to third parties.

SECURITIES AUTHORIZED FOR ISSUANCE UNDER EQUITY COMPENSATION PLANS

The information contained in Item 12 of this Form 10-K is incorporated by reference herein.

SHARE REPURCHASES

The following table summarizes the Company’s share repurchases for the fourth quarter of 2010:

The Company has not repurchased any shares under the Common Stock Repurchase Plan since August 16, 2007. It is prohibited from repurchasing any common shares through an authorized share repurchase program by terms of the CPP until the Company’s Series D preferred stock has been fully repaid or the U.S. Treasury otherwise ceases to own any such preferred stock.

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PERFORMANCE GRAPH

The following stock performance graph compares the five-year cumulative total return of Zions Bancorporation’s common stock with the Standard & Poor’s 500 Index and the KBW Bank Index which include Zions Bancorporation. The KBW Bank Index is a market capitalization-weighted bank stock index developed and published by Keefe, Bruyette & Woods, Inc., a nationally recognized brokerage and investment banking firm specializing in bank stocks. The index is composed of 24 geographically diverse stocks representing national money center banks and leading regional financial institutions. The stock performance graph is based upon an initial investment of $100 on December 31, 2005 and assumes reinvestment of dividends.

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FINANCIAL HIGHLIGHTS

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MANAGEMENT’S DISCUSSION AND ANALYSIS

EXECUTIVE SUMMARY

Company Overview

Zions Bancorporation (“the Parent”) and subsidiaries (collectively “the Company,” “Zions,” “we,” “our,” “us”) together comprise a $51 billion financial holding company headquartered in Salt Lake City, Utah. The Company is a “systemically important” financial institution, under the Dodd-Frank Act.

Core Long-Term Strategy

We strive to maintain a local community bank approach for customer-facing elements of our business. We believe that our target customers, consisting largely of small and mid-sized businesses, appreciate local branding, product customization, and speedy decision-making by local management. By retaining a significant degree of autonomy in product offerings and pricing, we believe our banks have a sustainable competitive advantage over larger national banks where loan and deposit products are often homogeneous. However, we strive to centralize non-customer facing operations, such as risk and capital management, technology and operations. By centralizing many of these functions, we believe we can generally achieve greater economies of scale and stronger risk management, and that our portfolio of community banks has superior access to the capital markets, investment portfolio, treasury management, and liquidity resources, and technological advances than do smaller independent community banks.

Our growth strategy is driven by four key factors:

Focus on Growth Markets

The Company seeks to grow both organically and through acquisitions in growth markets. The states in our geographic footprint have experienced higher rates of economic growth than other states. Our footprint is well diversified by industry, strong business formation rates, real estate development and general economic expansion. While some states in our footprint have experienced a significant slowing in economic activity during the recent recession, others have experienced above-average growth and stronger resistance to the economic

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downturn. We believe that the Company can continue to experience above-average revenue growth in the long term, in part because the majority of our footprint is concentrated in states that have above average GDP, population, and job growth, and where the economies are well diversified.

Keep Decisions That Affect Customers Local

We believe that over the long term, ensuring that local management teams retain the authority over decisions that affect their customers is a strategy that ultimately generates superior growth in our banking businesses, as supported by stronger organic loan and deposit growth relative to other banks.

Maintain a Sustainable Competitive Advantage Over Community Banks

To create a sustainable competitive advantage over other smaller community banks, we focus on achieving superior product selection, productivity, economies of scale, availability of liquidity, and a lower cost of capital. Compared to community banks:

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Centralize and Standardize Policies and Management Controlling Key Risks

We seek to standardize policies and practices related to the management of key risks in order to assure a consistent risk profile in an otherwise decentralized management model. Among these key risks and functions are credit, interest rate, liquidity, and market risks.

MANAGEMENT’S OVERVIEW OF 2010 PERFORMANCE

The Company worked aggressively in 2010 to reduce the risk within the loan portfolio, reduce problem credits, and meaningfully improve various capital ratios. The Company reported a net loss applicable to common shareholders for 2010 of $412.5 million or $2.48 per diluted common share compared to a net loss of $1,234.4 million or $9.92 per diluted common share for 2009.

Although we reported a net loss for 2010, we note that the trends that drive profitability have shown considerable signs of improvement, as detailed below.

Significant 2010 Accomplishments

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The reconciliation of controlling interest shareholders’ equity to Tier 1 common equity is found in the GAAP to non-GAAP reconciliation on page 88. Reserves consist of the allowance for loan losses and the reserve for unfunded lending commitments.

Areas experiencing weakness in 2010

Areas of focus for 2011