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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 (d) OF

THE SECURITIES EXCHANGE ACT OF 1934

BANCFIRST CORPORATION

(Exact name of registrant as specified in its charter)

101 North Broadway, Oklahoma City, Oklahoma 73102

(Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code:  (405) 270-1086

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

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

Common Stock, $1.00

Par Value Per Share

(Title of Class)

Indicate by check mark whether the registrant (1) has filed all reports required 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 if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K 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 an accelerated filer (as defined in Rule 12b-2 of the Act).    Yes  ¨    No  x

The aggregate market value of the Common Stock held by nonaffiliates of the registrant computed using the last sale price on June 28, 2002 was approximately $150,744,000.

As of February 28, 2003, there were 7,806,890 shares of Common Stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE:

Portions of the Proxy Statement for the May 22, 2003 Annual Meeting of Stockholders of registrant (the “2003 Proxy Statement”) to be filed pursuant to Regulation 14A are incorporated by reference into Part III of this report.

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FORM 10-K

CROSS-REFERENCE INDEX

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PART I

Item 1. Business.

General

BancFirst Corporation (the “Company”) is an Oklahoma business corporation and a financial holding company under Federal law. It conducts virtually all of its operating activities through its principal wholly-owned subsidiary, BancFirst (the “Bank” or “BancFirst”), a state-chartered, Federal Reserve member bank headquartered in Oklahoma City, Oklahoma. The Company also owns 100% of the common securities of BFC Capital Trust I, a Delaware Business Trust organized in January 1997, 75% of Century Life Assurance company, an Oklahoma chartered insurance company, and 100% of Council Oak Partners LLC, an Oklahoma limited liability company engaging in investing activities.

The Company was incorporated as United Community Corporation in July 1984 for the purpose of becoming a bank holding company. In June 1985, it merged with seven Oklahoma bank holding companies that had operated under common ownership and the Company has conducted business as a bank holding company since that time. Over the next several years the Company acquired additional banks and bank holding companies, and in November 1988 the Company changed its name to BancFirst Corporation. Effective April 1, 1989, the Company consolidated its 12 subsidiary banks and formed BancFirst. The Company has continued to expand through acquisitions and de-novo branches. BancFirst currently has 82 banking locations serving 41 communities throughout Oklahoma.

The Company’s strategy focuses on providing a full range of commercial banking services to retail customers and small to medium-sized businesses both in the non-metropolitan trade centers of Oklahoma and the metropolitan markets of Oklahoma City, Tulsa, Lawton, Muskogee, Norman and Shawnee. The Company operates as a “super community bank”, managing its community banking offices on a decentralized basis, which permits them to be responsive to local customer needs. Underwriting, funding, customer service and pricing decisions are made by Presidents in each market within the Company’s strategic parameters. At the same time, the Company generally has a larger lending capacity, broader product line and greater operational efficiencies than its principal competitors in the non-metropolitan market areas (which typically are independently-owned community banks). In the metropolitan markets served by the Company, the Company’s strategy is to focus on the needs of local businesses that are not served effectively by larger institutions.

The Bank maintains a strong community orientation by, among other things, appointing selected members of the communities in which the Bank’s branches are located to a local consulting board that assists in introducing prospective customers to the Bank and in developing or modifying products and services to meet customer needs. As a result of the development of broad banking relationships with its customers and the convenience and service of the Bank’s multiple offices, the Bank’s lending and investing activities are funded almost entirely by core deposits.

The Bank centralizes virtually all of its back office, support and investment functions in order to achieve consistency and cost efficiencies in the delivery of products and services. The Bank provides centralized services such as data processing, operations support, bookkeeping, accounting, loan review, compliance and internal auditing to the Bank’s community banking offices to enhance their ability to compete effectively. The Bank also provides centrally certain specialized financial services that require unique expertise. The community banking offices assist the Bank in maintaining its competitive position by actively participating in the development of new products and services needed by their customers and in making desirable changes to existing products and services.

The Bank provides a wide range of retail and commercial banking services, including: commercial, real estate, agricultural and consumer lending; depository and funds transfer services; collections; safe deposit boxes; cash management services; retail brokerage services; and other services tailored for both individual and corporate customers. The Bank also offers trust services and acts as executor, administrator, trustee, transfer agent and in various other fiduciary capacities. Through Unitech, its operations division, the Bank provides, item processing, research and other correspondent banking services to financial institutions and governmental units.

The Bank’s primary lending activity is the financing of business and industry in its market areas. Its commercial loan customers are generally small to medium-sized businesses engaged in light manufacturing, local wholesale and retail

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trade, services, agriculture, and the energy industry. Most forms of commercial lending are offered, including commercial mortgages, other forms of asset-based financing and working capital lines of credit. In addition, the Bank offers Small Business Administration (“SBA”) guaranteed loans through BancFirst Commercial Capital, a division established in 1991.

Consumer lending activities of the Bank consist of traditional forms of financing for automobiles, both direct and indirect, residential mortgage loans, home equity loans, and other personal loans. In addition, the Bank is one of Oklahoma’s largest providers of guaranteed student loans.

The Bank’s range of deposit services include checking accounts, NOW accounts, savings accounts, money market accounts, sweep accounts, club accounts, individual retirement accounts and certificates of deposit. Overdraft protection and autodraft services are also offered. Deposits of the Bank are insured by the Bank Insurance Fund administered by the Federal Deposit Insurance Corporation (“FDIC”). In addition, certain Bank employees are licensed insurance agents qualified to offer tax deferred annuities.

Trust services offered through BancTrust, the Bank’s trust division, consist primarily of investment management and administration of trusts for individuals, corporations and employee benefit plans. Investment options include collective equity and fixed income funds managed by BancTrust and advised by nationally recognized investment management firms.

BancFirst has the following principal subsidiaries: Council Oak Investment Corporation, a small business investment corporation; Citibanc Insurance Agency, Inc., a credit life insurance agency, which in turn owns BancFirst Agency, Inc., an insurance agency; Lenders Collection Corporation, which is engaged in collection of troubled loans assigned to it by BancFirst; and Express Financial Corporation (formerly National Express Corporation), a money order company. All of these companies are Oklahoma corporations. In addition, BancFirst owns Mojave Asset Management Company and Desert Asset Management Company, which in turn own Delamar Asset Management Limited Partnership. These three subsidiaries are Nevada companies and are engaged in investing in loan participations.

The Company had approximately 1,400 full-time equivalent employees as of December 31, 2002. Its principal executive offices are located at 101 North Broadway, Oklahoma City, Oklahoma 73102, telephone number (405) 270-1086.

Market Areas and Competition

The banking environment in Oklahoma is very competitive. The geographic dispersion of the Company’s banking locations presents several different levels and types of competition. In general, however, each location competes with other banking institutions, savings and loan associations, brokerage firms, personal loan finance companies and credit unions within their respective market areas. The communities in which the Bank maintains offices are generally local trade centers throughout Oklahoma. The major areas of competition include interest rates charged on loans, interest rates paid on deposits, levels of service charges on deposits, completeness of product line and quality of service.

Management believes the Company is in an advantageous competitive position operating as a “super community bank.” Under this strategy, the Company provides a broad line of financial products and services to small to medium-sized businesses and consumers through full service community banking offices with decentralized management, while achieving operating efficiency through product standardization and centralization of processing and other functions. Each full service banking office has senior management with significant lending experience who exercise substantial autonomy over credit and pricing decisions, subject to a tiered approval process for larger credits. This decentralized management approach, coupled with continuity of service by the same staff members, enables the Bank to develop long-term customer relationships, maintain high quality service and respond quickly to customer needs. The majority of its competitors in the non-metropolitan areas are much smaller, and neither offer the range of products and services nor have the lending capacity of BancFirst. In the metropolitan communities, the Company’s strategy is to be more responsive to, and more focused on, the needs of local businesses that are not served effectively by larger institutions.

Marketing to existing and potential customers is performed through a variety of media advertising, direct mail and direct personal contacts. The Company monitors the needs of its customer base through its Product Development

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Group, which develops and enhances products and services in response to such needs. Sales, customer service and product training are coordinated with incentive programs to motivate employees to cross-sell the Bank’s products and services.

Control of the Company

Affiliates of the Company beneficially own approximately 58.96% of the shares of the Common Stock outstanding. Under Oklahoma law, holders of a majority of the outstanding shares of Common Stock are able to elect all of the directors and approve significant corporate actions, including business combinations. Accordingly, the affiliates have the ability to control the business and affairs of the Company.

Recent Developments

In January 2003, BancFirst Corporation repurchased 320,000 shares of its common stock for $14.4 million. The shares were repurchased through a market-maker in the Company’s stock and was not a part of the Company’s ongoing Stock Repurchase Program.

Supervision and Regulation

The following discussion sets forth certain of the material elements of the regulatory framework applicable to bank holding companies and financial holding companies and their subsidiaries and provides certain specific information relevant to the Company, which is both a bank holding company and a financial holding company. This regulatory framework is intended primarily for the protection of depositors and not for the protection of the Company’s stockholders. To the extent that the following information describes statutory and regulatory provisions, it is qualified in its entirety by reference to those provisions. A change in the statutes, regulations or regulatory policies applicable to the Company or its subsidiaries may have a material effect on the business of the Company.

General

As a registered bank holding company and financial holding company, the Company is subject to the supervision of, and regular inspection by, the Board of Governors of the Federal Reserve System (the “Federal Reserve Board”). The Bank is organized as an Oklahoma state banking association, which is subject to regulation, supervision and examination by the Oklahoma State Banking Department, the Federal Deposit Insurance Corporation (the “FDIC”) and the Federal Reserve Board. In addition to banking laws, regulations and regulatory agencies, the Company and its subsidiaries and affiliates are subject to various other laws and regulations and supervision and examination by other regulatory agencies, all of which directly or indirectly affect the operations and management of the Company and its ability to make distributions to stockholders.

Financial Holding Company Regulation

A financial holding company, and the companies under its control, are permitted to engage in activities considered “financial in nature,” as defined by the Gramm-Leach-Bliley Act of 1999 (the “Gramm-Leach-Bliley Act”) and Federal Reserve Board interpretations (including, without limitation, insurance and securities activities), and therefore may engage in a broader range of activities than permitted for bank holding companies and their subsidiaries. The Gramm-Leach-Bliley Act also permits banks to engage in activities considered financial in nature through a “financial subsidiary,” subject to certain conditions and limitations and with the approval of the Federal Reserve Board.

For a bank holding company to engage in the broader range of activities that are permitted by the Gramm-Leach-Bliley Act, (1) all of its depository institutions must be “well capitalized” and “well managed,” as defined in Federal Reserve Regulation Y, and (2) it must file a declaration with the Board of Governors of the Federal Reserve System that it elects to be a “financial holding company” (“financial holding company”). See “Capital Adequacy Guidelines,” and “FDICIA and Related Regulations,” below, for a description of the capital guidelines for depository institutions. In addition, to commence any new permitted by the Gramm-Leach-Bliley Act and to acquire any company engaged in any new activities permitted by the Gramm-Leach-Bliley Act, each insured depository institution of the

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financial holding company must have received at least a “satisfactory” rating in its most recent examination under the Community Reinvestment Act (the “CRA”). Effective March 2000, the Company elected to become a financial holding company.

The Gramm-Leach-Bliley Act, which generally became effective March 11, 2000:

The Federal Reserve Board, by regulation, has determined that, subject to expressed limitations, the following activities are permissible for financial holding companies and may be engaged in, without providing prior notice to and without obtaining prior approval of the Federal Reserve Board:

A financial holding company may conduct any of these activities so long as the financial holding company notifies the Federal Reserve Board within 30 days after the financial holding company commences such activities or acquires a company that engages in such activities. If a financial holding company wishes to engage in activities that are “financial in nature or incidental to a financial activity” but not yet specifically authorized by the Federal Reserve Board, the financial holding company must file an application with the Federal Reserve Board. If both the Federal Reserve Board and Department of Treasury approve the application, the financial holding company may commence the new activity. The Federal Reserve Board may also approve a new activity that is complementary to a financial activity, but the financial holding company must make an additional showing that the activity does not pose a substantial risk to the safety and soundness of depository institutions or the financial system generally.

National banks are also authorized by the Gramm-Leach-Bliley Act to engage, through “financial subsidiaries, in any activity that is permissible for a financial holding company (as described above) and any activity that the Secretary of the Treasury, in consultation with the Federal Reserve Board, determines is financial in nature or incidental to any such financial activity, except (1) insurance underwriting, (2) real estate development or real estate investment activities (unless otherwise permitted by law), (3) insurance company portfolio investments and (4) merchant banking. The authority of a national bank to invest in a financial subsidiary is subject to a number of conditions, including, among other things, requirements that the bank must be well managed and well capitalized (after deducting from the bank’s capital outstanding investments in financial subsidiaries). The Gramm-Leach-Bliley Act provides that state banks may

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invest in financial subsidiaries (assuming they have the requisite investment authority under applicable state law) subject to the same conditions that apply to national bank investments in financial subsidiaries.

The Gramm-Leach-Bliley Act also modified laws related to financial privacy and community reinvestment. The new financial privacy provisions generally prohibit financial institutions, including the Company, from disclosing nonpublic personal financial information to third parties unless customers have the opportunity to “opt out” of the disclosure.

A bank holding company that does not elect to become a financial holding company may remain a bank holding company. A bank holding company’s regulatory requirements remain substantially the same with two exceptions. First, a bank holding company and its subsidiaries are subject to the new customer privacy regulations of the Gramm-Leach-Bliley Act. Second, a bank that engages in securities brokerage activities may be required, under certain circumstances, to move its securities brokerage activities to a subsidiary or non-bank affiliate that is a broker-dealer registered with the NASD.

The Gramm-Leach-Bliley Act preserves the role of the Federal Reserve Board as the umbrella supervisor for both financial holding companies and bank holding companies while at the same time incorporating a system of functional regulation designed to take advantage of the strengths of the various federal and state regulators. In particular, the Gramm-Leach-Bliley Act replaces the broad exemption from Securities and Exchange Commission (“SEC”) regulation that banks previously enjoyed with more limited exemptions, and it reaffirms that states are the regulators for the insurance activities of all persons, including federally-chartered banks.

Bank Holding Company Act and other Applicable Laws

Bank Holding Company Regulation

In addition to being a financial holding company, the Company remains a bank holding company and, as such, is regulated under the BHCA and is subject to the supervision of the Federal Reserve Board. Under the BHCA, bank holding companies that are not financial holding companies generally may not acquire the ownership or control of more than 5% of the voting shares, or substantially all the assets, of any company, including a bank or another bank holding company, without the Federal Reserve Board’s prior approval. Also, bank holding companies generally may engage only in banking and other activities that are determined by the Federal Reserve Board to be closely related to banking. The Federal Reserve Board has by regulation determined that such activities include operating a mortgage company, finance company, credit card company or factoring company; performing certain data processing operations; servicing loans and other extensions of credit; providing investment and financial advice; acting as an insurance agent for certain types of credit-related insurance; owning and operating savings and loan associations; and leasing personal property on a full pay-out, nonoperating basis. In the event a bank holding company elects to become a financial holding company, it would no longer be subject to the general requirements of the BHCA that it obtain the Federal Reserve Board’s approval prior to acquiring more than 5% of the voting shares, or substantially all of the assets, of a company that is not a bank or bank holding company. A bank holding company that does not qualify as a financial holding company is generally limited in the types of activities in which it may engage to those that the Federal Reserve Board had recognized as permissible for bank holding companies prior to the date of enactment of the Gramm-Leach-Bliley Act.

Control Acquisitions

Subject to certain exceptions, the Change in Bank Control Act (the “Control Act”) and regulations promulgated thereunder by the Federal Reserve Board require any person acting directly or indirectly, or through or in concert with one or more persons, to give the Federal Reserve 60 days’ written notice before acquiring control of a bank holding company. Transactions which are presumed to constitute the acquisition of control include the acquisition of any voting securities of a bank holding company having securities registered under section 12 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), if, after the transaction, the acquiring person (or persons acting in concert) owns, controls or holds with power to vote 25% or more of any class of voting securities of the institution. The acquisition may not be consummated subsequent to such notice if the Federal Reserve Board issues a notice within 60 days, or within certain extensions of such period, disapproving the same.

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Interstate Banking and Branching

Pursuant to the Riegle-Neal Interstate Banking and Branching Efficiency Act of 1994 (the “Interstate Banking and Branching Act”), a bank holding company may acquire banks in states other than its home state without regard to the permissibility of such acquisitions under state law, but subject to any state requirement that the bank has been organized and operating for a minimum period of time, not to exceed five years, and the requirement that the bank holding company, prior to or following the proposed acquisition, controls no more than 10 percent of the total amount of deposits of insured depository institutions in the United States and no more than 30 percent of such deposits in that state (or such lesser or greater amount set by state law). Legislation passed by the Oklahoma legislature in 2000 eliminated the previously existing requirement that Oklahoma banks be in existence for a minimum of five years before being acquired by, or merged into, another bank, or acquired by an existing bank holding company, and increased the “deposit cap” from 15% to 20%, with the result that a business combination involving Oklahoma-chartered banks may not result in the control by the combined institution of more than 20% of the total deposits of insured depositary institutions located in Oklahoma.

Subject to certain restrictions, the Interstate Banking and Branching Act also authorizes banks to merge across state lines, thereby creating interstate branches, without regard to whether such transactions are prohibited by the law of any state, unless the home state of one of the banks had “opted out” of interstate branching by enacting specific legislation prior to June 1, 1997, in which case out-of-state banks would generally not be able to branch into that state, and banks headquartered in that state would not be permitted to branch into other states. Oklahoma elected to “opt-in” to interstate branching effective May 1997 and established a 12.25% deposit cap that was subsequently increased to 20%. Furthermore, pursuant to the Interstate Banking and Branching Act, a bank may open new branches in a state in which it does not already have banking operations if such state enacts a law permitting such de novo branching. Oklahoma law permits de novo branching and, accordingly, Oklahoma state-chartered banks such as BancFirst are able to establish an unlimited number of de novo branches in Oklahoma.

Support for Bank Subsidiaries

The Federal Reserve Board has issued regulations under the BHCA that require a bank holding company to serve as a source of financial and managerial strength to its subsidiary banks. Pursuant to such regulations, the Federal Reserve Board may require the Company to stand ready to use its resources to provide adequate capital funds to its banking subsidiaries during periods of financial stress or adversity. Under the Federal Deposit Insurance Company Improvement Act of 1991 (“FDICIA”), a bank holding company is required to guarantee the compliance of any insured depository institution subsidiary that may become “undercapitalized” (as defined in the statute) with the terms of any capital restoration plan filed by such subsidiary with its appropriate federal banking agency, up to specified limits. See “FDICIA and Related Regulations,” below. Under the BHCA, the Federal Reserve Board has the authority to require a bank holding company to terminate any activity or relinquish control of a nonbank subsidiary (other than a nonbank subsidiary of a bank) upon the Federal Reserve Board’s determination that such activity or control constitutes a serious risk to the financial soundness and stability of any bank subsidiary of the bank holding company.

Capital Adequacy Guidelines

The Federal Reserve Board, the Comptroller and the FDIC have issued substantially similar risk-based and leverage capital guidelines applicable to United States banking organizations. In addition, these regulatory agencies may from time to time require that a banking organization maintain capital above the minimum levels, whether because of its financial condition or actual or anticipated growth. The Federal Reserve Board risk-based guidelines define a three-tier capital framework. Core, or “Tier 1,” capital, consists of common and qualifying preferred stockholders’ equity, less certain intangibles and other adjustments. Supplementary, or “Tier 2,” capital, includes, among other items, certain other debt and equity investments that do not qualify as Tier 1 capital. Market risk, or “Tier 3,” capital, includes qualifying unsecured subordinated debt. The sum of Tier 1 and Tier 2 capital less investments in unconsolidated subsidiaries represents qualifying total capital. Risk-based capital ratios are calculated by dividing Tier 1 and total capital by risk-weighted assets. Assets and off-balance sheet exposures are assigned to one of four categories of risk-weights, based primarily on relative credit risk. The minimum Tier 1 capital ratio is 4% and the minimum total capital ratio is 8%.

Applicable banking regulations also require banking organizations such as the Bank to maintain a minimum “leverage ratio” (Tier 1 capital to adjusted total assets) of 3%. The principal objective of this measure is to place a

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constraint on the maximum degree to which banks can leverage their equity capital base. These ratio requirements are minimums. Any institution operating at or near those levels would be expected by the regulators to have well-diversified risk, including no undue interest rate risk exposures, excellent asset quality, high liquidity, and good earnings and, in general, would have to be considered a strong banking organization. All other organizations and any institutions experiencing or anticipating significant growth are expected to maintain capital ratios at least one to two percent above the minimum levels, and higher capital ratios can be required if warranted by particular circumstances or risk profile.

The various regulatory agencies have adopted substantially similar regulations that define the five capital categories (well capitalized, adequately capitalized, undercapitalized, significantly undercapitalized and critically undercapitalized) for classifying insured depository institutions, using the total risk-based capital, Tier 1 risk-based capital and leverage capital ratios as the relevant capital measures, and requires the respective federal regulatory agencies to implement systems for “prompt corrective action” for insured depository institutions that do not meet minimum capital requirements within such categories. Such regulations establish various degrees of corrective action to be taken when an institution is considered undercapitalized.

To be “well capitalized” under federal bank regulatory agency definitions, a depository institution must have a Tier 1 ratio of at least 6%, a combined Tier 1 and Tier 2 ratio of at least 10%, and a leverage ratio of at least 5%. As of December 31, 2002, the Bank had a Tier 1 ratio of 10.14%, a combined Tier 1 and Tier 2 ratio of 11.38%, and a leverage ratio of 7.30% and, accordingly, was considered to be “well capitalized” as of such date.

In addition, the Federal Reserve Board has established minimum risk based capital guidelines and leverage ratio guidelines for bank holding companies that are substantially similar to those adopted by bank regulatory agencies with respect to depository institutions. These guidelines provide for a minimum leverage ratio of 3% for bank holding companies that meet certain specified criteria, including those having the highest regulatory rating. All other bank holding companies generally are required to maintain a leverage ratio of at least 4%. As of December 31, 2002, the company had a Tier 1 ratio of 12.03%, a combined Tier 1 and Tier 2 ratio of 13.25%, and a leverage ratio of 8.69% and, accordingly, was in compliance with all of the Federal Reserve Board’s capital guidelines.

FDICIA and Related Regulations

FDCIA, among other things, requires the respective Federal regulatory agencies to implement systems for “prompt corrective action” for insured depository institutions that do not meet minimum capital requirements within the five capital categories described above. FDICIA imposes progressively more restrictive constraints on operations, management and capital distributions, depending on the category in which an institution is classified. Failure to meet the capital guidelines could also subject a banking institution to capital raising requirements. An “undercapitalized” bank must develop a capital restoration plan and its parent holding company must guarantee that bank’s compliance with the plan. The liability of the parent holding company under any such guarantee is limited to the lesser of 5 percent of the bank’s assets at the time it became “undercapitalized” or the amount needed to comply with the plan. Furthermore, in the event of the bankruptcy of the parent holding company, such guarantee would take priority over the parent’s general unsecured creditors. In addition, FDICIA requires the various regulatory agencies to prescribe certain non-capital standards for safety and soundness relating generally to operations and management, asset quality and executive compensation and permits regulatory action against a financial institution that does not meet such standards.

Significantly or critically undercapitalized institutions and undercapitalized institutions that do not submit and comply with capital restoration plans acceptable to the applicable federal banking regulator are subject to one or more of the following sanctions: (i) forced sale of shares to raise capital, or, where grounds exist for the appointment of a receiver or conservator, a forced merger; (ii) restrictions on transactions with affiliates; (iii) limitations on interest rates paid on deposits; (iv) further restrictions on growth or required shrinkage; (v) replacement of directors or senior executive directors; (vi) prohibitions on the receipt of correspondent deposits; (vii) restrictions on capital distributions by the holding companies of such institutions; (viii) required divestiture of subsidiaries by the institution; or (ix) other restrictions, as determined by the regulator. In addition, the compensation of executive officers will be frozen at the level in effect when the institution failed to meet the capital standards and may be increased only with the applicable federal banking regulator’s prior written approval. The applicable federal banking regulator is required to impose a forced sale of shares or merger, restrictions on affiliate transactions and restrictions on rates paid on deposits unless it determines that such actions would not further an institution’s capital improvement. In addition to the foregoing, a critically

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undercapitalized institution would be prohibited from making any payment of principal or interest on subordinated debt without the concurrence of its regulator and the FDIC, beginning 60 days after the institution becomes critically undercapitalized. A critically undercapitalized institution may not, without FDIC approval: (i) enter into material transactions outside of the ordinary course of business; (ii) extend credit on highly leveraged transactions; (iii) amend its charter or bylaws; (iv) make any material change in its accounting methods; (v) engage in any covered transactions with affiliates; (vi) pay excessive compensation or bonus (as defined); or (vii) pay rates on liabilities significantly in excess of market rates. As of December 31, 2002 and the date of this Report, the Bank is considered “well capitalized.”

Federal banking regulations also provide that if an insured depository institution receives a less than satisfactory examination rating for asset quality, management, earnings, liquidity or interest rate sensitivity, or market risk, the examining agency may deem such financial institution to be engaging in an unsafe or unsound practice. The potential consequences of being found to have engaged in an unsafe or unsound practice are significant because the appropriate federal regulatory agency may:

Such evaluation will be made as a part of the institution’s regular safety and soundness examination. These guidelines did not have a material impact on the Company’s or BancFirst’s regulatory capital ratios or their well capitalized status.

Regulatory Restrictions on Dividends

BancFirst, as a member bank of the Federal Reserve System, may not declare a dividend without the approval of the Federal Reserve Board unless the dividend to be declared by BancFirst does not exceed the total of (i) BancFirst’s net profits (as defined and interpreted by regulation) for the current year to date plus (ii) its retained net profits (as defined and interpreted by regulation) for the preceding two years, less any required transfers to surplus. In addition, BancFirst can only pay dividends to the extent that its retained net profits (including the portion transferred to surplus) exceed its bad debts (as defined by regulation). Under the Federal Deposit Insurance Act, no dividends may be paid by an insured bank if the bank is in arrears in the payment of any insurance assessment due to the FDIC. Additionally, state and federal regulatory authorities have adopted standards for the maintenance of adequate levels of capital by banks. See “Capital Adequacy Guidelines,” above. Adherence to such standards further limits the ability of banks to pay dividends. The payment of dividends by any subsidiary bank may also be affected by other regulatory requirements and policies, such as the maintenance of adequate capital. If, in the opinion of the applicable regulatory authority, a bank under its jurisdiction is engaged in, or is about to engage in, an unsafe or unsound practice (which, depending on the financial condition of the bank, could include the payment of dividends), such authority may require, after notice and hearing, that such bank cease and desist from such practice. The Federal Reserve Board has formal and informal policies which provide that insured banks and bank holding companies should generally pay dividends only out of current operating earnings.

Deposit Insurance and Assessments

BancFirst is insured by the FDIC and is required to pay certain fees and premiums to the Bank Insurance Fund (“BIF”). These deposit insurance premiums are assessed through a risk-based system under which all insured depository institutions are placed into one of nine categories and assessed insurance premiums on deposits based upon their level of capital and supervisory evaluation, with the well-capitalized banks with the highest supervisory rating paying lower or no premiums and the critically undercapitalized banks paying up to 0.27% of deposits. BancFirst is currently being assessed at the lowest rate of zero percent.

Under the Deposit Insurance Funds Act of 1996 (the “Funds Act”), beginning in 1997 banks insured under the BIF were required to pay a part of the interest on bonds issued by the Financing Corporation (“FICO”) in the late 1980s

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to recapitalize the defunct Federal Savings and Loan Insurance Corporation. Before the Funds Act, FICO payments were made only by depository institutions that were members of the Savings Association Insurance Fund (the “SAIF”). Under the Funds Act, until January 1, 2000, BIF members were assessed for FICO payments at only one-fifth the rate of assessment on SAIF members. The Funds Act required that, as of January 1, 2000, all BIF- and SAIF- insured institutions pay FICO assessments at the same rate. For the first quarter of 2003, FICO rates have been set at .0168% for both BIF and SAIF members. The FICO assessment rates for both BIF and SAIF members for 2002 were:

State Regulation

BancFirst is an Oklahoma-chartered state bank. Accordingly, BancFirst’s operations are subject to various requirements and restrictions of state law relating to loans, lending limits, interest rates payable on deposits, investments, mergers and acquisitions, borrowings, dividends, capital adequacy, and other matters. Because BancFirst is a member of the Federal Reserve System, Oklahoma law provides that BancFirst must maintain reserves against deposits as required by the Federal Reserve Act. BancFirst is subject to primary supervision, periodic examination and regulation by the Oklahoma State Banking Department and the Federal Reserve Board. The Oklahoma State Bank Commissioner is authorized by statute to accept a Federal Reserve System examination in lieu of a state examination. In practice, the Federal Reserve Board and the Oklahoma State Banking Department alternate examinations of BancFirst. If, as a result of an examination of a bank, the Oklahoma State Banking Department determines that the financial condition, capital resources, asset quality, earnings prospects, management, liquidity, or other aspects of the bank’s operations are unsatisfactory or that the management of the bank is violating or has violated any law or regulation, various remedies, including the remedy of injunction, are available to the Oklahoma State Banking Department. Oklahoma also permits the acquisition of an unlimited number of wholly-owned bank subsidiaries so long as aggregate deposits at the time of acquisition in a multi-bank holding company do not exceed 20% of the total amount of deposits of insured depository institutions located in Oklahoma.

Governmental Monetary and Fiscal Policies

The commercial banking business is affected directly by the monetary policies of the Federal Reserve Board and by the fiscal policies of federal, state and local governments. The Federal Reserve Board, in fulfilling its role of stabilizing the nation’s money supply, utilizes several operating tools, all of which directly impact commercial bank operations. The primary tools used by the Federal Reserve Board are changes in reserve requirements on member bank deposits and other borrowings, open market operations in the U.S. Government securities market, and control over the availability and cost of members’ direct borrowings from the “discount window.” Banks act as financial intermediaries in the debt capital markets and are active participants in these markets daily. As a result, changes in governmental monetary and fiscal policies have a direct impact upon the level of loans and investments, the availability of sources of lendable funds, and the interest rates earned from and paid on these instruments. It is not possible to predict accurately the future course of such government policies and the residual impact upon the operations of the Company.

Recent Legislation

USA Patriot Act of 2001

In October 2001, the USA Patriot Act of 2001 (the “Patriot Act”) was enacted in response to the terrorist attacks in New York, Pennsylvania and Washington, D.C., which occurred on September 11, 2001. The Patriot Act is intended to strengthen U.S. law enforcement’s and the intelligence communities’ abilities to work cohesively to combat terrorism on a variety of fronts. The potential impact of the Patriot Act on financial institutions of all kinds is significant and wide ranging. The Patriot Act contains sweeping anti-money laundering and financial transparency laws and imposes various regulations, including standards for verifying client identification at account opening, and rules to promote cooperation among financial institutions, regulators and law enforcement entities in identifying parties that may be involved in terrorism or money laundering.

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Sarbanes-Oxley Act of 2002

On July 30, 2002, President Bush signed into law the Sarbanes-Oxley Act of 2002 (the “SOA”). The stated goals of the SOA are to increase corporate responsibility, to provide for enhanced penalties for accounting and auditing improprieties at publicly traded companies and to protect investors by improving the accuracy and reliability of corporate disclosures pursuant to the securities laws.

The SOA is the most far-reaching U.S. securities legislation enacted in recent history. The SOA generally applies to all companies, both U.S. and non-U.S., that file or are required to file periodic reports with the SEC under the Exchange Act. Given the extensive SEC role in implementing rules relating to many of the SOA’s new requirements, the final scope of these requirements remains to be determined.

The SOA includes very specific additional disclosure requirements and new corporate governance rules, requires the SEC and securities exchanges to adopt extensive additional disclosure, corporate governance and other related rules and mandates further studies of certain issues by the SEC and the Comptroller General. The SOA represents significant federal involvement in matters traditionally left to state regulatory systems, such as the regulation of the accounting profession, and to state corporate law, such as the relationship between a board of directors and management and between a board of directors and its committees.

The SOA addresses, among other matters: audit committees; certification of financial statements by the chief executive office and the chief financial officer; the forfeiture of bonuses and profits made by directors and senior officers in the twelve month period covered by restated financial statements; a prohibition on insider trading during pension plan back out periods; disclosure of off-balance sheet transactions; a prohibition on personal loans to directors and officers (excluding federally insured financial institutions); expedited filing requirements for stock transaction reports by officers and directors; disclosure of a code of ethics and filing a Form 8-K for a change or waiver of such code; “real time” filing of periodic reports; the formation of a public accounting oversight board; auditor independence; and various increased criminal penalties for violations of securities laws.

The SOA contains provisions that became effective upon enactment on July 30, 2002 and provisions that will become effective from within 30 days to one year from enactment. The SEC has been delegated the task of enacting rules to implement various of the provisions with respect to, among other matters, disclosure in periodic filings pursuant to the Exchange Act.

Regulation W

Transactions between a bank and its “affiliates” are governed by Sections 23A and 23B of the Federal Reserve Act. The Federal Reserve Board has also recently issued Regulation W, effective April 1, 2003, which codifies prior regulations under Sections 23A and 23B of the Federal Reserve Act and provides interpretative guidance with respect to affiliate transactions. Affiliates of a bank include, among other entities, the bank’s holding company and companies that are under common control with the bank. The Company is considered to be an affiliate of the Bank. In general, subject to certain specified exemptions, a bank or its subsidiaries are limited in their ability to engage in “covered transactions” with affiliates:

In addition, a bank and its subsidiaries may engage in covered transactions and other specified transactions only on terms and under circumstances that are substantially the same, or at least as favorable to the bank or its subsidiary, as those prevailing at the time for comparable transactions with nonaffiliated companies. A “covered transaction” includes:

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In addition, under Regulation W:

Pending and Proposed Legislation

There are various pending and proposed bills in Congress that, among other things, could restructure the federal supervision of financial institutions. The Company is unable to predict with any certainty the effect any such legislation would have on the Company, its subsidiaries or their respective activities. Additional legislation, judicial and administrative decisions also may affect the ability of banks to compete with each other as well as with other businesses. These statutes and decisions may tend to make the operations of various financial institutions more similar and increase competition among banks and other financial institutions or limit the ability of banks to compete with other businesses. Management currently cannot predict whether and, if so, when any such changes might occur or the impact any such changes would have upon the income or operations of the Company or its subsidiaries, or upon the Oklahoma regional banking environment.

Item 2. Properties.

The principal offices of the Company are located at 101 North Broadway, Oklahoma City, Oklahoma 73102. The Company owns substantially all of the properties and buildings in which its various offices and facilities are located. These properties include the main bank and 81 branches. BancFirst also owns properties for future expansion. There are no significant encumbrances on any of these properties.

Item 3. Legal Proceedings.

The Company has been named as a defendant in various legal actions arising from the conduct of its normal business activities. Although the amount of any liability that could arise with respect to these actions cannot be accurately predicted, in the opinion of the Company, any such liability will not have a material adverse effect on the consolidated financial position of the Company.

Item 4. Submission of Matters to Vote of Security Holders.

There were no matters submitted to a vote of security holders, through the solicitation of proxies or otherwise, during the fourth quarter of the year ended December 31, 2002.

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PART II

Item 5. Market for the Company’s Common Stock and Related Stockholder Matters.

The Company’s Common Stock is listed on the Nasdaq National Market System (“NASDAQ/NMS”) and is traded under the symbol “BANF”. The following table sets forth, for the periods indicated, (i) the high and low sales prices of the Company’s Common Stock as reported in the NASDAQ/NMS consolidated transaction reporting system and (ii) the quarterly dividends declared on the Common Stock.

As of February 28, 2003 there were approximately 400 holders of record of the Common Stock.

Future dividend payments will be determined by the Company’s Board of Directors in light of the earnings and financial condition of the Company and the Bank, their capital needs, applicable governmental policies and regulations and such other factors as the Board of Directors deems appropriate.

BancFirst Corporation is a legal entity separate and distinct from the Bank, and its ability to pay dividends is substantially dependent upon dividend payments received from the Bank. Various laws, regulations and regulatory policies limit the Bank’s ability to pay dividends to BancFirst Corporation, as well as BancFirst Corporation’s ability to pay dividends to its shareholders. See “Liquidity and Funding” and “Capital Resources” under “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” “Description of Business—Supervision and Regulation” and Note 14 of the Notes to Consolidated Financial Statements for further information regarding limitations on the payment of dividends by BancFirst Corporation and the Bank.

Item 6. Selected Financial Data.

Incorporated by reference from “Selected Consolidated Financial Data” contained on page A-3 of the attached Appendix.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

Incorporated by reference from “Financial Review” contained on pages A-2 through A-15 of the attached Appendix.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk.

Incorporated by reference from “Financial Review—Market Risk” contained on page A-15 of the attached Appendix.

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Item 8. Financial Statements and Supplementary Data.

The consolidated financial statements of BancFirst Corporation and its subsidiaries, are incorporated by reference from pages A-16 through A-46 of the attached Appendix, and include the following:

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure.

There have been no material disagreements between the Company and its independent accountants on accounting and financial disclosure matters which are required to be reported under this Item for the period for which this report is filed.

PART III

Item 10. Directors and Executive Officers of the Registrant.

The information required by Item 401 of Regulation S-K will be contained in the 2003 Proxy Statement under the caption “Election of Directors” and is hereby incorporated by reference. The information required by Item 405 of Regulation S-K will be contained in the 2003 Proxy Statement under the caption “Compliance with Section 16(a) of the Securities Exchange Act of 1934” and is hereby incorporated by reference.

Item 11. Executive Compensation.

The information required by Item 402 of Regulation S-K will be contained in the 2003 Proxy Statement under the caption “Compensation of Directors and Executive Officers” and is hereby incorporated by reference.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.

The information required by Item 201(d) of Regulation S-K will be contained in the 2003 Proxy Statement under the caption “Securities Authorized for Issuance under Equity Compensation Plans” and is hereby incorporated by reference. The information required by Item 403 of Regulation S-K will be contained in the 2003 Proxy Statement under the caption “Security Ownership of Certain Beneficial Owners and Management” and is hereby incorporated by reference.

Item 13. Certain Relationships and Related Transactions.

The information required by Item 404 of Regulation S-K will be contained in the 2003 Proxy Statement under the caption “Transactions with Management” and is hereby incorporated by reference.

Item 14. Controls and Procedures.

The Company’s Chief Executive Officer and Chief Financial Officer have evaluated the Company’s disclosure controls and procedures as of a date within 90 days of the filing date of this report. Based on their evaluation they concluded that the disclosure controls and procedures of the Company are adequate to ensure that information required to be disclosed by the Company in the reports filed or submitted by it under the Securities Exchange Act of 1934 is recorded, processed, summarized and reported, within the time periods specified in the applicable rules and forms. There have been no significant changes in the Company’s internal controls or in other factors that could significantly affect disclosure controls subsequent to the date of their evaluation.

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PART IV

Item 15. Exhibits, Financial Statement Schedules, and Reports on Form 8-K.

Report of Independent Accountants

Consolidated Balance Sheet at December 31, 2002 and 2001

Consolidated Statement of Income for the three years ended December 31, 2002

Consolidated Statement of Stockholders’ Equity for the three years ended December 31, 2002

Consolidated Statement of Cash Flows for the three years ended December 31, 2002

Notes to Consolidated Financial Statements

The above financial statements are incorporated by reference from pages A-16 through A-45 of the attached Appendix.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities indicated on March 28, 2003.

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CERTIFICATIONS

I, David E. Rainbolt, certify that:

a)  designed such disclosure controls and procedures to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this quarterly report is being prepared;

b)  evaluated the effectiveness of the registrant’s disclosure controls and procedures as of a date within 90 days prior to the filing date of this annual report (the “Evaluation Date “); and

c)  presented in this annual report our conclusions about the effectiveness of the disclosure controls and procedures based on our evaluation as of the Evaluation Date;

a)  all significant deficiencies in the design or operation of internal controls which could adversely affect the registrant’s ability to record, process, summarize and report financial data and have identified for the registrant’s auditors any material weaknesses in internal controls; and

b)  any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal controls; and

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I, Joe T. Shockley, Jr., certify that:

a)  designed such disclosure controls and procedures to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this quarterly report is being prepared;

b)  evaluated the effectiveness of the registrant’s disclosure controls and procedures as of a date within 90 days prior to the filing date of this annual report (the “Evaluation Date “); and

c)  presented in this annual report our conclusions about the effectiveness of the disclosure controls and procedures based on our evaluation as of the Evaluation Date;

a)  all significant deficiencies in the design or operation of internal controls which could adversely affect the registrant’s ability to record, process, summarize and report financial data and have identified for the registrant’s auditors any material weaknesses in internal controls; and

b)  any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal controls; and

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APPENDIX A

BancFirst Corporation

INDEX TO FINANCIAL STATEMENTS

AND SUPPLEMENTARY DATA

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FINANCIAL REVIEW

The following discussion is an analysis of the financial condition and results of operations of the Company for the three years ended December 31, 2002 and should be read in conjunction with the Consolidated Financial Statements and Notes thereto and the Selected Consolidated Financial Data included herein.

SUMMARY

BancFirst Corporation achieved its twelfth year of record earnings in 2002, with nearly every measure of the Company’s financial performance improving for the year. Net income grew 20% to $33.6 million from $28 million for 2001, as a result of loan growth, a stable net interest margin, moderate loan losses, increased noninterest income, and the elimination of goodwill amortization. Diluted earnings per share grew 21.6% to $4.06 from $3.34 for 2001. Return on average assets increased to 1.22% from 1.05%, and return on average equity increased to 14.33% from 13.32% for 2001.

Total assets increased to $2.8 billion, or 1.44%, from $2.76 billion at year-end 2001. Total loans grew $97.4 million, or 5.67%, to $1.81 billion, while total deposits grew $27.3 million, or 1.14%, to $2.43 billion. The Company’s average loans to deposits increased to 73.89% from 72.12% for 2001. Stockholders’ equity increased $28.3 million, or 12.7%, to $252 million. Tangible book value per share increased to $28.25 from $24.34 at the end of 2001, an increase of 16.1%. Average stockholder’s equity to average assets increased to 8.53% from 7.86%.

Asset quality remained stable in 2002 with nonperforming and restructured assets to total assets increasing slightly to 0.60%, from 0.58% at year-end 2001. The allowance for loan losses to nonperforming and restructured loans was 175.16% at December 31, 2002, compared to 184.24% at the end of 2001.

The Company has continued to repurchase shares of its common stock under its ongoing Stock Repurchase Program (the “SRP”). During 2002, 186,599 shares were repurchased, compared to 119,519 shares in 2001. At December 31, 2002, there were 289,901 shares remaining that could be repurchased under the SRP. In January 2003, the Company repurchased 320,000 shares for $14.4 million, which was not a part of the SRP.

While 2002 was one of the Company’s most successful years, it will be challenging to maintain such level of performance in 2003. Continued historically low, or possibly even lower, interest rates would be expected to further compress the Company’s net interest margin. Slow economic growth could have an adverse effect on loan growth and asset quality. Additionally, recent changes in corporate governance, reporting and other regulatory requirements will result in higher costs. The Company will address these challenges over the coming year.

The Company’s principal subsidiary, BancFirst, is Oklahoma’s largest state-chartered bank and is the second largest Oklahoma-based bank. The Company has 82 banking locations serving 41 communities across Oklahoma.

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SELECTED CONSOLIDATED FINANCIAL DATA

(Dollars in thousands, except per share data)

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CONSOLIDATED AVERAGE BALANCE SHEETS AND INTEREST MARGIN ANALYSIS

Taxable Equivalent Basis (Dollars in thousands)