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                       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


[X]      Annual Report Pursuant to Section 13 or 15(d) of the
         Securities Exchange Act of 1934
         For the fiscal year ended December 31, 1999

                                       OR

[ ]      Transition Report Pursuant to Section 13 or 15(d) of the
         Securities Exchange Act of 1934
         For the transition period from __________ to __________

                         Commission File Number 0-17000
                    COMMERCIAL NATIONAL FINANCIAL CORPORATION
             (Exact name of registrant as specified in its charter)

                 Michigan                            38-2799780
       (State of Incorporation)             (I.R.S. Employer Identification No.)

       101 North Pine River Street
           Ithaca, Michigan                             48847
   (Address of principal executive offices)           (Zip Code)

       Registrant's telephone number, including area code: (517) 875-4144

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

                           Common Stock, No par value
                                (Title of Class)

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 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. /X/

State the aggregate market value of the voting stock held by non-affiliates of
the registrant. The aggregate market value shall be computed by reference to the
price at which the stock was sold, or the average bid and asked prices of such
stock, as of a specified date within 60 days prior to the date of filing.

            Aggregate market value as of March 13, 2000: $30,157,731

Indicate the number of shares outstanding of each of the registrant's classes of
common stock, as of the latest practicable date.

         Common Stock outstanding as of March 13, 2000: 3,203,413 shares

                       DOCUMENTS INCORPORATED BY REFERENCE

Portions of the registrant's annual report to security holders for the year
ended December 31, 1999, are incorporated by reference in Part II and Part IV.

Portions of the registrant's proxy statement for its April 25, 2000, annual
shareholders meeting are incorporated by reference in Part III.

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                                     PART I

ITEM 1. BUSINESS

Commercial National Financial Corporation (the "Corporation" or "registrant"), a
bank holding company, was incorporated in Michigan on December 30, 1987. On May
31, 1988, the Corporation acquired all of the stock of Commercial National Bank,
a national banking association chartered in 1962. On December 30, 1992,
Commercial National Bank converted to a state-chartered bank under the name
Commercial Bank (the "Bank").

The Bank's business is concentrated in a single industry segment - commercial
banking. The Bank provides a full range of banking services to individuals,
agricultural businesses, commercial businesses and light industries located in
its service area. The Bank maintains a diversified loan portfolio, including
loans to individuals for home mortgages, automobiles and personal expenditures,
and loans to business enterprises for current operations and expansion. The Bank
offers a variety of deposit vehicles, including checking, savings, money market,
individual retirement accounts and certificates of deposit.

The principal markets for the Bank's financial services are the mid-Michigan
communities in which the Bank is located and the areas immediately surrounding
these communities. The Bank serves these markets through seven offices located
in and near these communities. Neither the Corporation nor the Bank has any
material foreign assets or income.

The principal source of revenue for the Corporation and its subsidiary is
interest and fees on loans. On a consolidated basis, interest and fees on loans
accounted for 80.14% of the Corporation's total revenues in 1999, 76.45% in
1998, and 80.00% in 1997. Interest on investment securities accounted for 10.91%
of the Corporation's total revenues in 1999, 11.27% in 1998, and 9.89% in 1997.

At December 31, 1999, the Bank had no significant concentrations of loans to any
group of borrowers engaged in similar activities that would be impacted by
economic or other conditions.

The business of banking is highly competitive. In addition to competition from
other commercial banks, banks face competition from non-bank financial
institutions. Savings associations compete with commercial banks for deposits
and loans. Credit unions and finance companies compete for consumer loans.
Commercial banks compete for deposits with other entities such as mutual funds
and corporate and government debt securities. Financial service providers
compete for customers principally through price (interest rates paid on
deposits, interest rates charged on borrowings and fees charged for services)
and service (convenience and quality of services rendered to customers).

The Bank competes directly with fifteen financial institutions in the market it
serves. The Bank's competitors include other commercial banks, savings
associations and local credit unions. The Bank ranks second in deposit size when
compared to the total deposits of the branches located in the market the Bank
serves. The Bank does not believe that its ability to compete for loans and
deposits is affected by the rank among its competitors.

Banks and bank holding companies are extensively regulated. The Bank is
chartered as a state bank under Michigan law and is supervised, examined and
regulated by the Michigan Financial Institutions Bureau and the Federal Deposit
Insurance Corporation ("FDIC"). The business activities of the registrant are
limited to banking and to other activities determined by the Board of Governors
of the Federal Reserve System to be closely related to banking. Deposits of the
Bank are insured by the FDIC to the extent provided by law.

Commercial banks are subject to a number of federal and state laws and
regulations that have a material impact on their business. These include, among
others, state usury laws, state laws relating to fiduciaries, the Truth in
Lending Act, the Equal Credit Opportunity Act, the Fair Credit Reporting Act,
the Expedited Funds Availability Act, the Community Reinvestment Act, electronic
funds transfer laws, redlining laws, antitrust laws, environmental laws and
privacy laws. The policies of the Federal Reserve System, and other authorities,
may materially affect the growth and distribution of loans, investments and
deposits and interest rates on deposits and loans.

The FDIC Improvement Act of 1991 (the "FDIC Improvement Act"), revised sections
of the Federal Deposit Insurance Act affecting bank regulation, deposit
insurance and provisions for the funding of the bank insurance fund. The FDIC
Improvement Act also revised bank regulatory structures embodied in several
other federal banking statutes, links the bank regulators' authority



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to intervene to the deterioration of a bank's capital level, places limits on
real estate lending and increases audit requirements. Among the significant
revisions that could have an impact on the Corporation is the authority granted
to the FDIC to impose special assessments on insured depository institutions to
repay FDIC borrowings from the United States Treasury or other sources and to
establish semiannual assessment rates on bank insurance fund member banks so as
to maintain the bank insurance fund at the designated reserve ratio defined in
the FDIC Improvement Act. The FDIC Improvement Act also required the FDIC to
implement a system of risk-based premiums for deposit insurance pursuant to
which the premiums paid by a depository institution are based on the perceived
probability that the bank insurance fund will incur a loss in respect of such
institution.

Under 1994 amendments to the Federal Bank Holding Company Act, the Corporation
is authorized to acquire subsidiary banks in any state in which state laws
permit such acquisitions. Out-of-state bank holding companies in any state are
permitted to acquire banks located in Michigan if the laws of the state in which
the out-of-state bank holding company is located authorize a bank holding
company located in Michigan to acquire ownership of banks in that state on a
reciprocal basis. Under amendments to the Michigan Banking Code which became
effective on November 29, 1995, the Bank is authorized to merge with or acquire
out-of-state banks or branches in any state in which state laws permit such
acquisitions.

Enacted late in 1999, the Gramm-Leach-Bliley Act ("Gramm-Leach-Bliley"),
broadens the scope of financial services that banks may offer to consumers,
essentially removing the barriers erected during the Depression that separated
banks and securities firms, closes the loophole which permitted commercial
enterprises to own and operate a thrift institution, and provides some new
consumer protections with respect to privacy issues and ATM usage fees.
Gramm-Leach-Bliley permits affiliations between banks, securities firms and
insurance companies (which affiliations were previously prohibited under the
Glass-Steagall Act). Under Gramm-Leach-Bliley, a bank holding company may
qualify as a financial holding company and thereby offer expanded range of
financial oriented products and services which products and services may not be
offered by bank holding companies. To qualify as a financial holding company, a
bank holding company's subsidiary depository institutions must be well-managed,
well-capitalized and have received a "satisfactory" rating on its oversight by
the Securities and Exchange Commission of bank holding companies engaged in
certain activities, and reaffirms that insurance activities are to be regulated
on the state level. States, however, may not prevent depository institutions and
their affiliates from engaging in insurance activities. Commercial enterprises
are no longer able to establish or acquire a thrift institution and thereby
become a unitary thrift holding company. Thrift institutions may only be
established or acquired by financial organizations. Gramm-Leach-Bliley provides
new consumer protections with respect to the transfer and use of a consumer's
nonpublic personal information and generally enables financial institution
customers to "opt-out" of the dissemination of their personal financial
information to unaffiliated third parties. ATM operators who charge a fee to
non-customers for use of its ATM must disclose the fee on a sign placed on the
ATM and before the transaction is made as a part of the on-screen display or by
a paper notice issued by the machine.

ITEM 2. PROPERTIES.

The Bank currently conducts business from seven banking offices. The executive
offices of the Corporation are located at 101 North Pine River Street, Ithaca,
Michigan. The main office of the Bank is located at 301 North State Street,
Alma, Michigan. The main office property of the Bank is leased for a term
expiring on December 31, 2013. The branches of the Bank are located in Alma,
Greenville, Middleton, Pompeii, and St. Louis, Michigan.

The Bank owns the property for five of the branch office locations. One branch
office is leased pursuant to a lease that expires August 1, 2008, subject to 2
renewals of 10 years each. The Corporation considers all of its facilities to be
well maintained and in generally good operating condition and suitable for the
purposes for which they are intended.

ITEM 3. LEGAL PROCEEDINGS.

The Corporation and the Bank are parties, as plaintiff or defendant, to several
legal proceedings, none of which is considered material, and all of which arose
in the ordinary course of business.

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.

Not applicable.




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                                     PART II

ITEM 5.  MARKET FOR THE REGISTRANT'S COMMON EQUITY AND RELATED SHAREHOLDER
MATTERS.

The information under the captions "Common Stock Information" and "Dividend
Information" of the registrant's annual report to shareholders for the year
ended December 31, 1999, is here incorporated by reference to Exhibit 13.

ITEM 6.  SELECTED FINANCIAL DATA.

The information under the caption "Selected Financial Data" of the registrant's
annual report to shareholders for the year ended December 31, 1999, is here
incorporated by reference to Exhibit 13.

ITEM 7.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
OF OPERATIONS.

The information under the heading "Management's Discussion and Analysis and
Results of Operations" of the registrant's annual report to shareholders for the
year ended December 31, 1999, is here incorporated by reference to Exhibit 13.

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

The information under the heading "Quantitative and Qualitative Disclosures
About Market Risk" of the registrant's annual report to shareholders for the
year ended December 31, 1999, is here incorporated by reference to Exhibit 13.

ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

The financial statements, notes and report of independent auditors' included in
the registrant's annual report to shareholders for the year ended December 31,
1999, are here incorporated by reference to Exhibit 13.

ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
FINANCIAL DISCLOSURE.

Not applicable




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                                    PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT.

The information set forth under the caption "Directors and Executive Officers"
and "Section 16(a) Beneficial Ownership Reporting Compliance" in the
registrant's definitive Proxy Statement for its April 25, 2000, annual meeting
of shareholders is here incorporated by reference.

ITEM 11. EXECUTIVE COMPENSATION.

The information set forth under the captions "Compensation of Executive
Officers" and "Compensation of Directors" in the registrant's definitive Proxy
Statement for its April 25, 2000, annual meeting of shareholders is here
incorporated by reference.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT.

The information set forth under the caption "Voting Securities" in the
registrant's definitive Proxy Statement for its April 25, 2000, annual meeting
of shareholders is here incorporated by reference.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS.

The information set forth under the caption "Certain Relationships" in the
registrant's definitive Proxy Statement for its April 25, 2000, annual meeting
of shareholders is here incorporated by reference.



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                                     PART IV

ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K.

       (a)(1)  Financial Statements.

The following financial statements, notes to financial statements, and report of
independent auditor of the Corporation and its subsidiary are filed as part of
this report:

               Independent Auditors' Reports
               Consolidated Balance Sheets - December 31, 1999 and 1998
               Consolidated Statements of Income for each of the three years
               ended December 31, 1999, 1998 and 1997
               Consolidated Statements of Shareholders' Equity for each of the
               three years ended December 31, 1999, 1998 and 1997
               Consolidated Statements of
               Cash Flows for each of the three years ended
               December 31, 1999, 1998 and 1997
               Notes to Consolidated Financial Statements

The financial statements, notes to financial statements, and report of
independent auditor for the years ended December 31, 1999, 1998 and 1997 listed
above are incorporated by reference in Item 8 of this report from the
corresponding portions of the registrant's annual report to shareholders for the
year ended December 31, 1999. With the exception of the portions of the
registrant's annual report to shareholders for the year ended December 31, 1999
specifically incorporated herein by reference, such report shall not be deemed
filed as part of this annual report on Form 10-K.

               (2) All schedules have been omitted because they are inapplicable
or otherwise not required.

               (3) The following exhibits are filed as part of this report:

<TABLE>
<CAPTION>
             Number                            Exhibit
             ------                            -------
           <S>       <C>
              3(a)    Restated Articles of Incorporation. Previously filed as an
                      exhibit to the registrant's Form S-4 filed January 22,
                      1988. Here incorporated by reference.

              3(b)    Bylaws. Previously filed as an exhibit to the registrant's
                      Form S-4 filed January 22, 1988. Here incorporated by
                      reference.

             10(a)    1991 Stock Option Plan. Previously filed as an exhibit to
                      the registrant's Form 10-K for the year ended December 31,
                      1990. Here incorporated by reference.*

             10(b)    Amendment to 1991 Stock Option Plan. Previously filed as
                      an exhibit to the registrant's Form 10-K for the year
                      ended December 31, 1995. Here incorporated by reference.*

             10(c)    Lease for Main Office. Previously filed as an exhibit to
                      registrant's Form 10-K for the year ended December 31,
                      1991. Here incorporated by reference.


             10(d)    Amendment to 1991 Stock Option Plan. Previously filed as
                      an exhibit to the registrant's Form 10-K for the year
                      ended December 31, 1998. Here incorporated by reference.*

             10(e)    Change in Control Agreement. Previously filed as an
                      exhibit to the registrant's Form 10-K for the year ended
                      December 31, 1998. Here incorporated by reference.*

             13       Incorporated Portions from 1999 Annual Report to
                      Shareholders.


             21       Subsidiary of Registrant. Previously filed as an exhibit
                      to the registrant's Form S-4 filed January 22, 1988. Here
                      incorporated by reference.

</TABLE>
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<TABLE>
            <S>      <C>
             23       Consent of Certified Public Accountants.

             27       Financial Data Schedule.

             *  Management contract or compensatory plan or arrangement.
</TABLE>
The registrant will furnish a copy of any exhibit listed above to any
shareholder of the registrant without charge upon written request to Patrick
Duffy, Commercial National Financial Corporation, 101 North Pine River Street,
Ithaca, Michigan 48847.
<TABLE>
             <S> <C>
             (b) Reports on Form 8-K.

                 No reports were filed for the fourth quarter of 1999.

             (c) Exhibits.

                 See Item 14(a)(3)

             (d) Financial Statement Schedules.
</TABLE>
                 There are no financial statement schedules required to be filed
 with this report.




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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.

                                      COMMERCIAL NATIONAL FINANCIAL CORPORATION
                                      (registrant)

March 24, 2000                        By: /s/ Jeffrey S. Barker
                                          --------------------------------------
                                      Jeffrey S. Barker
                                      President and Chief Executive Officer







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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 and on the dates indicated.
<TABLE>

<S>                              <C>
March 24, 2000                   /s/ Jeffrey S. Barker
                                 -----------------------------------------------
                                 Jeffrey S. Barker
                                 Director, President and Chief Executive Officer
                                 (Principal Executive Officer)

March 24, 2000                   /s/ Richard F. Abbott
                                 -----------------------------------------------
                                 Richard F. Abbott
                                 Director

March 24, 2000                   /s/ Jefferson P. Arnold
                                 -----------------------------------------------
                                 Jefferson P. Arnold
                                 Director

March 24, 2000                   /s/ Don J. Dewey
                                 -----------------------------------------------
                                 Don J. Dewey
                                 Director

March 24, 2000                   /s/ David A. Ferguson
                                 -----------------------------------------------
                                 David A. Ferguson
                                 Director

March 24, 2000                   /s/ Kenneth R. Luneack
                                 -----------------------------------------------
                                 Kenneth R. Luneack
                                 Director

March 24, 2000                   /s/ Kim C. Newson
                                 -----------------------------------------------
                                 Kim C. Newson
                                 Director

March 24, 2000                   /s/ Howard D. Poindexter
                                 -----------------------------------------------
                                 Howard D. Poindexter
                                 Director

March 24, 2000                   /s/ Scott E. Sheldon
                                 -----------------------------------------------
                                 Scott E. Sheldon
                                 Director

March 24, 2000                   /s/ Patrick G. Duffy
                                 -----------------------------------------------
                                 Patrick G. Duffy
                                 Director
                                 (Principal Financial and Accounting Officer)

</TABLE>


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                                INDEX TO EXHIBITS

<TABLE>
<CAPTION>

Number                                Exhibit                                    Page
------                                -------                                    ----
<S>             <C>                                                             <C>
  3(a)            Restated Articles of Incorporation. Previously filed as an       *
                  exhibit to the registrant's Form S-4 filed January 22, 1988.
                  Here incorporated by reference.

  3(b)            Bylaws. Previously filed as an exhibit to the registrant's       *
                  Form S-4 filed January 22, 1988. Here incorporated by
                  reference.


 10(a)            1991 Stock Option Plan. Previously filed as an exhibit to the    *
                  registrant's Form 10-K for the year ended December 31, 1990.
                  Here incorporated by reference.

 10(b)            Amendment to 1991 Stock Option Plan. Previously filed as an      *
                  exhibit to the registrant's Form 10-K for the year ended
                  December 31, 1995. Here incorporated by reference.

 10(c)            Lease for Main Office. Previously filed as an exhibit to         *
                  registrant's Form 10-K for the year ended December 31, 1991.
                  Here incorporated by reference.

 10(d)            Amendment to 1991 Stock Option Plan. Previously filed as an      *
                  exhibit to registrant's Form 10-K for the year ended December
                  31, 1999. Here incorporated by reference.


 10(e)            Change in Control Agreement. Previously filed as an exhibit to    *
                  registrant's Form 10-K for the year ended December 31, 1999.
                  Here incorporated by reference.

 13               Incorporated Portions from 1999 Annual Report to Shareholders.    10

 21               Subsidiary of Registrant. Previously filed as an exhibit to       *
                  the registrant's Form S-4 filed January 22, 1988. Here
                  incorporated by reference.

 23               Consent of Independent Certified Public Accountants.              11

 27               Financial Data Schedule.                                          13
</TABLE>

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*This exhibit is filed by incorporation by reference to a prior filing.



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