<PAGE>   1
                       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

                  For the Fiscal Year Ended December 31, 1999
                         Commission File Number 0-11928

                             AMERICAN BANCORP, INC.
             (Exact name of registrant as specified in its charter)

        Louisiana                                      72-0951347
(State or other jurisdiction of                     (I.R.S. Employer
incorporation or organization)                      Identification No.)

      321 East Landry Street
       Opelousas, Louisiana                                  70570
(Address of principal executive offices)                   (Zip Code)

Registrant's Telephone Number, including area code: (318) 948-3056

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

Securities registered pursuant to Section 12(g) of the Act:
                            Common Stock, $5.00 Par Value
                                   (Title of Class)

Indicate by check mark whether the registrant: (l) 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. [ ]

The aggregate market value of the voting stock held by non-affiliates* of the
registrant:  $4,066,518.

The number of shares outstanding of each of the issuer's classes of common
stock, as of December 31, 1999: Common Stock, $5.00 Par Value, 117,712 shares
outstanding.

                       Documents Incorporated by Reference

Portions of the annual shareholders' report for the year ended December 31, 1999
are incorporated by reference into Parts I and II.

Portions of the proxy statement for the annual shareholders meeting to be held
April 12, 2000 are incorporated by reference into Part III.




                                      - 1 -
<PAGE>   2



     *For purposes of the computation, shares owned by executive officers,
directors, 5% shareholders and shares by non-affiliates whose voting rights have
been assigned to directors have been excluded.









                                      - 2 -
<PAGE>   3



                                     PART I


Item 1. Business

     American Bancorp, Inc. (the Company) was incorporated under the laws of the
State of Louisiana in 1982. On October 1, 1983, American Bank and Trust Company
(the Bank) was reorganized as a subsidiary of the Company. Prior to October 1,
1983, the Company had no material activity. The Company is currently engaged,
through its subsidiary, in banking and related business. The Bank is the
Company's principal asset and primary source of revenue.

The Bank

     The Bank, incorporated under the State Banking Laws on August 1, 1958 is in
the business of gathering funds by accepting checking, savings, and other
time-deposit accounts and reemploying these by making loans and investing in
securities and other interest-bearing assets. The Bank is a full service
commercial bank. Some of the major services which it provides include checking,
NOW accounts, Money Market checking, savings, and other time deposits of various
types, loans for business, agriculture, real estate, personal use, home
improvement, automobile, and a variety of other types of loans and services
including letters of credit, safe deposit boxes, bank money orders, wire
transfer facilities, and electronic banking facilities.

     The State of Louisiana, through its various departments and agencies,
deposits public funds with the Bank. However, as of December 31, 1999, the State
of Louisiana did not have any funds on deposit with the Bank.

     The Bank's general market area is in St. Landry Parish, which has a
population of approximately 81,939. Its primary market is Opelousas, which has a
population of approximately 19,540, and has experienced little population growth
over the past several years.

     The commercial banking business in St. Landry Parish is highly competitive.
The Depository Institutions Deregulation and Monetary Control Act of 1980 and
the Garn-St. Germain Depository Institutions Act of 1982 have eliminated most,
if not all, substantive distinctions between the services of commercial banks
and thrift institutions. The Bank competes with three banks and two savings and
loan institutions located in St. Landry Parish. The following is a list of banks
and savings associations in this market with the total deposits and assets as of
December 31, 1999.


<TABLE>
<CAPTION>
                                                         (In thousands of dollars)
                                                            Assets       Deposits
                                                         ----------     ----------
<S>                                                      <C>            <C>
American Bank and Trust Company                          $   80,232     $   70,434
St. Landry Bank and Trust Company                        $  213,121     $  180,829
St. Landry Homestead                                     $  154,988     $  120,471
Washington State Bank                                    $   78,988     $   67,032
First Federal Savings & Loan                             $   75,680     $   46,562
</TABLE>







                                      - 3 -
<PAGE>   4



Item 1.  Business (continued)


     In addition to the institutions listed above, further competition is
provided by banks and other financial institutions located in Lafayette,
Louisiana, which is 20 miles south of Opelousas and Baton Rouge, Louisiana, the
state capital, which is 60 miles east of St. Landry Parish.

     The banking industry is extensively regulated under both federal and state
law. The Company is subject to regulation under the Bank Holding Company Act of
1956 (BHCA) and to supervision by the Board of Governors of the Federal Reserve
System (FRB). The BHCA requires the Company to obtain the prior approval of the
FRB for bank acquisitions and prescribes certain limitations in connection with
acquisitions and the non-banking activities of the Company. The Bank is subject
to regulation and examination by the Louisiana Office of Financial Institutions
and the Federal Deposit Insurance Corporation.

     The Federal Deposit Insurance Corporation Improvement Act of 1991 (FDICIA)
further expanded the regulatory and enforcement powers of bank regulatory
agencies. Among the significant provisions of FDICIA is the requirement that
bank regulatory agencies prescribe standards relating to internal controls,
information systems, loan documentation, credit underwriting, interest rate
exposure, asset growth, compensation, fees and benefits. FDICIA mandates annual
examinations of banks by their primary regulators.

     The banking industry is affected by the monetary and fiscal policies of the
FRB. An important function of the FRB is to regulate the national supply of bank
credit to moderate recessions and to curb inflation. Among the instruments
monetary policy used by the FRB to implement its objectives are: open-market
operations of U.S. Government securities, changes in the discount rate and the
federal funds rate (which is the rate banks charge each other for overnight
borrowings) and changes in reserve requirements on bank deposits.

Employees

     During 1999, the average number of full-time equivalent employees at the
Bank was 44. This includes the officers of the Company that are listed under
Item 1 below.

     There are no unions or bargaining units that represent the employees of the
Bank. The relation between management and employees is considered to be good.






                                      - 4 -

<PAGE>   5


Item 1.  Business (continued)


Executive Officers

     The executive officers of the Company are as follows:

<TABLE>
<CAPTION>
                                       Years of
   Officer Name                         Service                Age              Position Currently Held
----------------------                 ---------               ---              --------------------------------
<S>                                    <C>                     <C>              <C>
Salvador L. Diesi, Sr.                     26                   69              Chairman of the Board of the
                                                                                  Company and the Bank;
                                                                                  President of the Company
                                                                                  and the Bank

Ronald J. Lashute                          27                   50              Executive Vice-President and
                                                                                  Chief Executive Officer of the
                                                                                  Bank and Secretary/Treasurer
                                                                                  of the Company
</TABLE>

     None of the directors and executive officers of the Company or the Bank
holds a directorship in any company with a class of securities registered under
Section 12 of the Securities Exchange Act of 1934, as amended, or subject to the
requirements of Section 15(d) of that Act or in any company registered as an
investment company under the Investment Company Act of 1940. Salvador L. Diesi,
Sr. and Ronald J. Lashute are the nephews of J.C. Diesi. No other family
relationships exist among the above named directors or executive officers of the
Company.

Supervision and Regulation

     The Bank is subject to regulation and regular examinations by the Louisiana
Commissioner of Financial Institutions and by the Federal Deposit Insurance
Corporation. Applicable regulations relate to reserves, investments, loans,
issuance of securities, establishment of branches, and other aspects of its
operations.

     The Federal Deposit Insurance Corporation Improvement Act of 1991
("FDICIA") further expanded the regulatory and enforcement powers of bank
regulatory agencies. Among the significant provisions of FDICIA is the
requirement that bank regulatory agencies prescribe standards relating to
internal controls, information systems, loan documentation, credit underwriting,
interest rate exposure, asset growth, compensation, fees and benefits. FDICIA
mandates annual examinations of banks by their primary regulators.

     The Company is a bank holding company within the meaning of the Bank
Holding Company Act of 1956, as amended (the Act), and is thereby subject to the
provisions of the Act and to regulation by the Board of Governors of the Federal
Reserve System (the Board).






                                      - 5 -

<PAGE>   6


Item 1.  Business (continued)


     The Act requires the Company to file with the Board an annual report
containing such information as the Board may require. The Board is authorized by
the Act to examine the Company and all of its activities. The activities that
may be engaged in by the Company and its subsidiary are limited by the Act to
those so closely related to banking or managing or controlling banks as to be a
proper incident thereto. In determining whether a particular activity is a
proper incident to banking or managing or controlling banks, the Board must
consider whether its performance by an affiliate of a holding company can
reasonably be expected to produce benefits to the public, such as greater
convenience, increased competition or gains in efficiency that outweigh possible
adverse effects, such as undue concentration of resources, decreased or unfair
competition, conflicts of interest, or unsound banking practices.

     The Board has adopted regulations implementing the provisions of the Act
with respect to the non-banking activities of bank holding companies. Such
regulations reflect a determination by the Board that certain specified
activities are permissible for a bank holding company. An activity not listed in
the regulation may be engaged in if, upon application, the Board determines that
the activity meets the criteria described in the preceding paragraph. In each
case, a bank holding company must secure the approval of the Board prior to
engaging in any of these activities.

     Whether or not a particular non-banking activity is permitted under the
Act, the Board is authorized to require a holding company to terminate any
activity, or divest itself of any non-banking subsidiary, if in its judgment the
activity or subsidiaries would be unsound.

     Under the Act and the Board's regulations, a bank holding company and its
subsidiaries are prohibited from engaging in certain tie-in arrangements in
connection with any extension of credit or provision of any property or
services.

     In some cases, the Company must receive the prior approval of the Board in
order to repurchase or redeem its outstanding equity securities.

     With certain exceptions, the Subsidiary Bank is restricted by Sections 22
and 23A of the Federal Reserve Act from extending credit or making loans to or
investments in the Company and certain other affiliates as defined in the
Federal Reserve Act. Such transactions by the Subsidiary Bank with the Company
or any such affiliate are limited in an amount to 10% of the Subsidiary Bank's
capital and surplus. Furthermore, loans and extensions of credit are subject to
various collateral requirements.

     The Louisiana bank holding company law, as amended (the "Louisiana Act"),
permits bank holding companies to own more than one bank. In addition, a bank
holding company and its subsidiaries may not engage in any insurance activity in
which a bank may not engage. The Louisiana Commissioner of Financial
Institutions is authorized to administer the Louisiana Act and to issue orders
and regulations.

     The Board of Directors of the Company have no present plans or intentions
to cause the Company to engage in any substantial business activity which would
be permitted to it under the Act or the Louisiana Act but which is not permitted
to the Bank; however, a significant reason for formation of the one-bank holding
company is to take advantage of the additional flexibility afforded by that
structure if the Board of Directors of the Company concludes that such action
would be in the best interest of stockholders.




                                      - 6 -

<PAGE>   7


Item 1.  Business (continued)


Statistical Information

     The following tables contain additional information concerning the business
and operations of the Registrant and its subsidiary and should be read in
conjunction with the Consolidated Financial Statements of the Registrant and
Management's Discussion and Analysis of Financial Condition and Results of
Operations. The 1999 Annual Report to Shareholders is incorporated herein by
reference under Item 8.

Investment Portfolio

     The following table sets forth the carrying amount of Investment Securities
at the dates indicated (in thousands of dollars):


<TABLE>
<CAPTION>
                                                         December 31,
                                           -------------------------------------
                                             1999           1998          1997
                                           ---------     ---------     ---------
<S>                                        <C>           <C>           <C>
Securities held to maturity:
   U.S. Treasury                           $   2,300     $   2,696     $   3,692
   U.S. Government Agencies                      500         3,005        10,512
                                           ---------     ---------     ---------

                                           $   2,800     $   5,701     $  14,204
                                           =========     =========     =========
</TABLE>



<TABLE>
<CAPTION>
                                                         December 31,
                                           -------------------------------------
                                             1999           1998          1997
                                           ---------     ---------     ---------
<S>                                        <C>           <C>           <C>
Securities available for sale:
   Mortgage-backed securities              $   6,931     $   4,455     $   1,210
   U.S. Treasury securities                    3,501         3,553         2,009
   U.S. Government Agencies                   12,536         9,002         5,532
   State and Political subdivisions            8,306         6,907         3,442
   Equity securities                             149            97            --
                                           ---------     ---------     ---------

                                           $  31,423     $  24,014     $  12,193
                                           =========     =========     =========
</TABLE>






                                      - 7 -

<PAGE>   8


Item 1.  Business (continued)


     The following tables set forth the maturities of investment securities at
December 31, 1999, 1998, and 1997 and the weighted average yields of such
securities (in thousands of dollars):


<TABLE>
<CAPTION>
                                                                       December 31, 1999
                             -----------------------------------------------------------------------------------
                                                       After One           After Five
                                                       But Within          But Within              After
                                Within One Year        Five Years          Ten Years              Ten Years
                             -------------------     --------------    ------------------    -------------------
                               Amount      Yield     Amount   Yield      Amount     Yield      Amount      Yield
                             --------    -------     ------   -----    --------   -------    ---------   -------
<S>                          <C>         <C>         <C>      <C>      <C>         <C>       <C>            <C>
Securities held
  to maturities:
    U.S. Treasury            $     200   4.54%       $ 2,100  5.44%    $      --      --%    $     --          --%
    U.S. Government
      Agencies                      --     --            500  6.43            --      --           --          --
                             ---------               -------           ---------             --------

       Total held
         to maturity               200   4.54          2,600  5.63           -0-      --          -0-          --
                             ---------               -------           ---------             --------

Securities
   available for
   sale:
      U.S. Treasury              3,501   5.75             --    --          --        --           --          --
      U.S. Government
         Agencies                   --     --          9,635  6.12        2,901     6.62           --          --
      Mortgage-backed
         securities                 --     --          2,004  6.04          444     5.61        4,483         6.58
      State and
         Political
         Subdivisions              529   7.37          4,093  6.84        3,186     7.23          498         7.43
      Equity
         securities                149     --             --    --          --        --           --          --
                             ---------               -------            --------              --------

            Total
              available
              for sale           4,179   5.96         15,732  6.30         6,531    6.85        4,981         6.66
                             ---------             ---------           ---------             --------

            Total
              securities     $   4,379   5.89%     $  18,332  6.20%    $   6,531    6.85%    $  4,981         6.66%
                             =========   =====     ========= =====     =========  ======     ========       ======
</TABLE>




                                      - 8 -

<PAGE>   9


Item 1.  Business (continued)


<TABLE>
<CAPTION>
                                                                       December 31, 1998
                             -------------------------------------------------------------------------------------------------
                                                           After One                  After Five
                                                           But Within                 But Within               After
                                Within One Year            Five Years                 Ten Years                Ten Years
                             ---------------------   ----------------------     ----------------------   ---------------------
                               Amount      Yield       Amount       Yield        Amount       Yield        Amount      Yield
                             ---------   ---------   ----------   ---------     ---------   ----------   ----------  ---------
<S>                          <C>         <C>         <C>          <C>          <C>         <C>           <C>         <C>
Securities held
   to maturities:
      U.S. Treasury          $   2,496        6.25%   $     200        4.54%    $      --           --%   $      --         --%
      U.S. Government
      Agencies                     506        6.22        1,999        6.91           500         7.03           --         --
                             ---------                ---------                 ---------                  ---------

            Total held
              to maturity        3,002        6.24        2,199        6.69           500         7.03           -0-        --
                             ---------                ---------                 ---------                  ---------

Securities
   available for
   sale:
      U.S. Treasury                 --          --        3,553        5.75            --           --           --         --
      U.S. Government
         Agencies                   --          --        7,966        6.25         1,036         6.06           --         --
      Mortgage-backed
         securities                 --          --          669        6.85         2,301         5.77        1,485       6.82
      State and
         Political
         Subdivisions              222        7.48        3,011        7.16         3,113         7.12          561       7.11
      Equity
         securities                 97          --           --          --            --           --           --         --
                             ---------                ---------                 ---------                 ---------

            Total
              available
              for sale             319        7.48       15,199        6.34         6,450         6.47        2,046         6.90
                             ---------                ---------                 ---------                 ---------

            Total
              securities     $   3,321        6.33%   $  17,398        6.38%    $   6,950         6.51%   $   2,046         6.90%
                             =========    ========    =========   =========     =========    =========    =========    =========
</TABLE>





                                      - 9 -

<PAGE>   10
Item 1.  Business (continued)



<TABLE>
<CAPTION>
                                                                       December 31, 1997
                             -------------------------------------------------------------------------------------------------
                                                            After One               After Five
                                                            But Within              But Within                 After
                                Within One Year             Five Years               Ten Years                Ten Years
                             ---------------------   -----------------------    --------------------    ---------------------
                               Amount      Yield       Amount       Yield        Amount      Yield        Amount      Yield
                             ---------   ---------   ---------    ---------    ---------   ---------    ---------   ---------
<S>                          <C>         <C>         <C>          <C>          <C>         <C>          <C>         <C>

Securities held
   to maturities:
      U.S. Treasury          $   1,200        5.95%   $   2,492        6.25%   $      --          --%   $      --          --%
      U.S. Government
      Agencies                   2,498        5.92        7,016        6.49          998        7.16           --          --
                             ---------                ---------                ---------                ---------

            Total held
              to maturity        3,698        5.93        9,508        6.43          998        7.16          -0-          --
                             ---------                ---------                ---------                ---------

Securities
   available for
   sale:
      U.S. Treasury              1,001        6.27        1,008        6.28           --          --           --          --
      U.S. Government
         Agencies                   --          --        5,532        6.53           --          --           --          --
      Mortgage-backed
         securities                  4        9.35          407        8.66           68        9.16          731        8.66
      State and
         Political
         Subdivisions               10        6.43        2,006        7.29        1,221        7.01          205        8.68
                             ---------                ---------                ---------                ---------

            Total
              available
              for sale           1,015        6.28        8,953        6.76        1,289        7.11          936        8.67
                             ---------                ---------                ---------                ---------

            Total
              securities     $   4,713        6.01%   $  18,461        6.59%   $   2,287        7.13%   $     936        8.67%
                             =========   =========    =========   =========    =========   =========    =========   =========
</TABLE>


* Weighted average yields have been computed on a fully tax-equivalent basis
assuming a rate of 34% for 1999, 1998 and 1997.





                                     - 10 -

<PAGE>   11


Item 1.  Business (continued)


Loan Portfolio

     The amounts of loans outstanding at the indicated dates are shown in the
following table according to type of loan (in thousands of dollars):


<TABLE>
<CAPTION>
                                                             December 31,
                                             ------------------------------------------
                                                1999            1998            1997
                                             ----------      ----------      ----------
<S>                                          <C>             <C>             <C>
Commercial, financial and agricultural       $    7,326      $    7,666      $    7,549
Real Estate - Construction                          949              51             359
Real Estate - Mortgage                           15,809          15,361          15,543
Installment                                       4,748           4,981           4,984
                                             ----------      ----------      ----------

          Total                                  28,832          28,059          28,435

Less:
  Allowance for possible loan losses               (579)           (596)           (600)
  Unearned income                                    --              --              --
                                             ----------      ----------      ----------

                                             $   28,253      $   27,463      $   27,835
                                             ==========      ==========      ==========
</TABLE>


     The following table presents information concerning the aggregate amount of
nonperforming loans. Nonperforming loans comprise: (a) loans accounted for on a
nonaccrual basis; (b) loans contractually past due ninety days or more as to
interest or principal payments [but not included in the nonaccrual loans in (a)
above];(c) other loans whose terms have been restructured to provide a reduction
or deferral of interest or principal because of a deterioration in the financial
position of the borrower [exclusive of loans in (a) or (b) above]; and (d) loans
now current where there are serious doubts as to the ability of the borrower to
comply with present loan requirement terms (in thousands of dollars):


<TABLE>
<CAPTION>
                                                            December 31,
                                             ------------------------------------------
                                                1999            1998            1997
                                             ----------      ----------      ----------
<S>                                          <C>             <C>             <C>
Loans accounted for on a nonaccrual basis    $       70      $      145      $      308

Restructured loans which are not on
  non-accrual                                        39              61              70
                                             ----------      ----------      ----------

                                                    109            206              378
Other real estate and repossessed assets
  received in complete or partial
  satisfaction of loan obligations                   --              --               7
                                             ----------      ----------      ----------

    Total nonperforming assets               $      109      $      206      $      385
                                             ==========      ==========      ==========

Loans contractually past due ninety days
  or more as to principal or interest,
  but which were not on non-accrual          $        8      $       15      $        9
                                             ==========      ==========      ==========
</TABLE>







                                     - 11 -

<PAGE>   12


Item 1.  Business (continued)



     As of January 1, 1995, the Company adopted SFAS No. 114, "Accounting by
Creditors for Impairment of a Loan," which, as it relates to in-substance
foreclosures, requires that a creditor continue to classify these assets as
loans in the balance sheet unless the creditor receives physical possession of
the collateral. The Company had no in-substance foreclosures at the date of
adoption of SFAS No. 114. At December 31, 1999, the recorded investment in loans
that were considered to be impaired under SFAS No. 114 was $64,000, with the
related allowance for loan losses of $10,000. These loans are included in
nonaccrual loans.

     The effect of nonperforming loans on interest income has not been
substantial in the past three years. Had interest been accrued on the
nonperforming loans, interest income would have been recorded in the amount of
$9,501, $32,424 and $53,417, for the years 1999, 1998, and 1997, respectively.
Interest income in the amount of $2,733, $4,796 and $5,621 on nonperforming
loans during 1999, 1998 and 1997, respectively, was recorded.

     At December 31, 1999, 1998 and 1997 there were no significant commitments
to lend additional funds to debtors whose loans were considered to be
nonperforming.

     The Bank places loans on nonaccrual when the borrower is no longer able to
make periodic interest payments due to a deterioration of the borrowers
financial condition.

     At December 31, 1999, the Bank has an insignificant amount of loans for
which payments are current, but the borrowers are experiencing financial
difficulties. These loans are subject to constant management attention, and
their classification is reviewed on a monthly basis.

Summary of Loan Loss Experience

     The following table summarizes loan balances at the end of each period and
average loans based on daily average balances for 1999, 1998, and 1997; changes
in the allowance for possible loan losses arising from loans charged off and
recoveries on loans previously charged off by loan category; and additions to
the allowance which have been charged to expense (in thousands of dollars):


<TABLE>
<CAPTION>
                                          1999         1998          1997
                                        --------     --------     --------
<S>                                     <C>          <C>          <C>
Amount of loans outstanding
  at end of period                      $ 28,832     $ 28,058     $ 28,435
                                        ========     ========     ========

Average amount                          $ 26,880     $ 28,548     $ 27,797
                                        ========     ========     ========
</TABLE>




                                     - 12 -

<PAGE>   13
Item 1.  Business (continued)


Allowance for Possible Loan Losses
(In thousands of dollars)


<TABLE>
<CAPTION>
                                                               Year Ended December 31,
                                                       --------------------------------------
                                                         1999            1998          1997
                                                       --------       --------       --------
<S>                                                    <C>            <C>            <C>
Beginning balance                                      $    596       $    600       $    614
Provision charged against income                             --             --             --
                                                       --------       --------       --------
                                                       $    596            600            614
                                                       --------       --------       --------
Charge-offs:
  Commercial, financial and
    agricultural loans                                      (13)            --             (1)
  Real estate mortgage loans                                 --             --             --
  Real estate construction loans                             --             --             --
  Installment loans                                          (7)           (15)           (16)
                                                       --------       --------       --------
    Total charge-offs                                       (20)           (15)           (17)
                                                       --------       --------       --------

Recoveries:
  Commercial, financial and agricultural loans               --             --             --
  Real estate mortgage loans                                 --             --             --
  Real estate construction loans                             --             --             --
  Installment loans                                           3             11              3
                                                       --------       --------       --------
                                                              3             11              3
                                                       --------       --------       --------

Net (charge-offs) recoveries                                (17)            (4)           (14)
                                                       --------       --------       --------

Ending balance                                         $    579       $    596       $    600
                                                       ========       ========       ========

Ratio of net (charge-offs) recoveries
  during the period to average loans
  outstanding during the period                            (.06)%         (.01)%         (.05)%
                                                       ========       ========       ========
</TABLE>

     The allowance for possible loan losses has been allocated according to the
amount deemed to be reasonably necessary to provide for the possibility of
losses being incurred within the following categories of loans at the date
indicated:

Allocation of Allowance for Possible Loan Losses
(In thousands of dollars)


<TABLE>
<CAPTION>
                                        December 31, 1999               December 31, 1998
                                   --------------------------      ------------------------
                                                   % of Loans                   % of Loans
                                                  Outstanding                   Outstanding
                                                    to Total                    to Total
                                   Allowance         Loans       Allowance        Loans
                                   ---------      -----------    ---------      -----------
<S>                                <C>            <C>            <C>            <C>
Commercial, financial and
  agricultural loans               $     120          25.41%     $     135          27.32%
Real estate construction                   5           3.29              1            .18
Real estate mortgage loans               238          54.83            272          54.75
Installment loans                        216          16.47            188          17.75
                                   ---------      ---------      ---------      ---------

                                   $     579         100.00%     $     596         100.00%
                                   =========      =========      =========      =========
</TABLE>





                                     - 13 -

<PAGE>   14
Item 1.  Business (continued)


Allocation of Allowance for Possible Loan Losses (continued)
(In thousands of dollars)


<TABLE>
<CAPTION>
                                           December 31, 1997
                                   --------------------------------
                                                       % of Loans
                                                       Outstanding
                                                        to Total
                                     Allowance            Loans
                                   -------------      -------------
<S>                                <C>                <C>
Commercial, financial and
  agricultural loans                      $  218              26.55%
Real estate construction                       5               1.27
Real estate mortgage loans                    97              54.66
Installment loans                            280              17.52
                                          ------             ------

                                          $  600             100.00%
                                          ======             ======
</TABLE>



Deposits

     The average amount of deposits, using daily average balances for 1999,
1998, and 1997, is summarized for the periods indicated in the following table
(in thousands of dollars):


<TABLE>
<CAPTION>
                                                    Year Ended December 31,
                                             -------------------------------------
                                                1999          1998         1997
                                             ---------     ---------     ---------
<S>                                          <C>           <C>           <C>
Non-interest bearing demand deposits ...       $23,962       $19,070       $16,846
Interest-bearing demand deposits .......        10,838        11,104        11,752
Savings deposits .......................         9,714         9,223         8,374
Time deposits ..........................        22,030        19,747        19,003
                                               -------       -------       -------

                                               $66,544       $59,144       $55,975
                                               =======       =======       =======
</TABLE>


Return on equity and assets

     The ratio of Net Income to Average Shareholders' Equity and to Average
Total Assets, and certain other ratios, are as follows:


<TABLE>
<CAPTION>
                                                          Year Ended December 31,
                                                 --------------------------------------
                                                   1999           1998            1997
                                                 --------       --------         ------
<S>                                              <C>            <C>              <C>
Percentage of net income to:
  Average total assets                               1.42%          1.47%          1.47%
  Average shareholders' equity                      11.38%         11.27%         11.70%

Percentage of dividends declared per
  common share to net income per
  common share                                      15.74%         14.76%         13.92%

Percentage of average shareholders'
  equity to daily average total assets              12.47%         13.06%         12.58%
</TABLE>



                                     - 14 -

<PAGE>   15


Item 1.  Business (continued)


Short-Term Borrowing

     The Company's short-term borrowing and the average interest rate thereon at
the end of the last three years, are as follows (in thousands of dollars):


<TABLE>
<CAPTION>
                                                 Year Ended December 31,
                                         --------------------------------------
                                            1999         1998            1997
                                         ---------     ---------      ---------
<S>                                      <C>           <C>            <C>
Balance at December 31                   $      --     $      --      $      --
Weighted average interest rate at
  year end                                      -- %          -- %           -- %
Maximum amount outstanding at any
  month's end                            $      --     $      --      $      --
Average amount outstanding during
  the year                               $      --     $      29      $      --
Weighted average interest rate
  during the year                               -- %        6.90%            -- %
</TABLE>


Item 2. Properties

     The main office of the Company and the Bank are presently located at 321
East Landry Street, Opelousas, Louisiana, in the downtown business district. The
Bank leases four branch sites. The building in which the main office is located
is free of all mortgages.

     For information with respect to the Company obligations under its lease
commitments, see Note 9 to the Consolidated Financial Statements, which are
incorporated herein by reference under Item 8.


Item 3. Legal Proceedings

     The Company is not involved in any legal actions; however, there are
presently pending by the Bank a number of legal proceedings. It is the opinion
of management that the resulting liability, if any, from these actions and other
pending claims will not materially affect the consolidated financial statements.


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

     No matters were submitted during the fourth quarter of the fiscal year
covered by this report to a vote of security holders, through the solicitation
of proxies or otherwise.




                                     - 15 -

<PAGE>   16



                                     PART II

Item 5. Market for Registrant's Common Stock and Related Security Holder Matters


                       MARKET PRICE AND DIVIDENDS DECLARED

<TABLE>
<CAPTION>
                                                                                                         Dividends
               Year               Quarter                    High                   Low                  Per Share
              ------             ---------                  ------                ------                ----------
<S>                              <C>                        <C>                   <C>                   <C>
               1999              First                      $   60                $   60                    $  -
                                 Second                         61                    61                       -
                                 Third                          61                    61                       -
                                 Fourth                         62                    62                     1.45

               1998              First                      $   53                $   53                    $  -
                                 Second                         55                    55                       -
                                 Third                          57                    57                       -
                                 Fourth                         60                    30                     1.25
</TABLE>


     Note: The primary market area for American Bancorp, Inc.'s common stock is
the Opelousas, Louisiana area with American Bank and Trust Company acting as
registrar and transfer agent. There were approximately 516 shareholders of
record at December 31, 1999.

     Source of market price - American Bank & Trust Company acts as the transfer
agent for the Company. The stock is thinly traded and the price ranges are based
on stated sales price to the transfer agent, which does not represent all sales.


RESTRICTIONS ON CASH DIVIDENDS PAYABLE BY THE REGISTRANT:

     The only source of funds by the Company to pay dividends is dividends paid
by the Subsidiary Bank, the payment of which is restricted by applicable federal
and state statutes.

     Federal bank regulatory authorities have authority under the Financial
Institutions Supervisory Act to prohibit a bank from engaging in an unsafe or
unsound practice. The payment of a dividend by the Bank could, depending upon
the financial condition of the Bank and other factors be deemed an unsafe or
unsound practice.

     Applicable Louisiana law prohibits a state bank subsidiary from paying a
dividend if its surplus remaining after payment of the dividend would be less
than half the aggregate par value of its outstanding stock. In addition, a state
bank subsidiary is required to obtain the prior approval of the Commissioner of
Financial Institutions of Louisiana before declaring or paying a dividend in a
given year if the total of all dividends declared or paid during that year would
exceed the total of its net profits for that year combined with the net profits
from the immediately preceding year.






                                     - 16 -

<PAGE>   17



Item 6. Selected Financial Data

     The information called for by Item 6 is included in Registrant's Annual
Report on page 5 in the Section titled "Summary of Operations for the Last Five
Years" and is incorporated herein by reference.

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

     The information called for by Item 7 is included in the Registrant's Annual
Report in the section titled "Management's Discussion and Analysis of
Operations" and is incorporated herein by reference.


Item 8. Financial Statements and Supplementary Data

     The following consolidated financial statements of the Registrant and its
subsidiary included on pages 28 through 56 in the Annual Report are incorporated
herein by reference:

     Consolidated Balance Sheets - December 31, 1999 and 1998

     Consolidated Statements of Income - Years Ended December 31, 1999,
            1998, and 1997
     Consolidated Statements of Shareholders' Equity - Years Ended
            December 31, 1999, 1998, and 1997
     Consolidated Statements of Cash Flows - Years Ended December 31, 1999,
            1998, and 1997
     Notes to Consolidated Financial Statements


Item 9. Disagreements in Accounting and Financial Disclosure

     There have been no disagreements with an independent accountant on any
matter of accounting principles or practice, financial disclosure, auditing
scope or procedure.


                                    PART III

Item 10. Directors and Executive Officers

     With the exception of identification of executive officers of the Company,
the information called for by Item 10 is omitted pursuant to General Instruction
G(3) and is included in Registrant's definitive Proxy Statement filed pursuant
to Section 14(a). Executive officers of the Company are identified in Item 1,
"Executive Officer," included in Part I of this report.


Item 11. Management Remuneration and Transactions

     The information called for by this item is included in Registrant's
definitive Proxy Statement filed pursuant to Section 14(a) of the Securities
Exchange Act of 1934 and is incorporated herein by reference.





                                     - 17 -

<PAGE>   18



Item 12. Security Ownership of Certain Beneficial Owners and Management


     The information called for by this item is included in Registrant's
definitive Proxy Statement filed pursuant to Section 14(a) of the Securities
Exchange Act of 1934 and is incorporated herein by reference.


Item 13. Certain Relationships and Related Transactions

     The information called for by this item is included in Registrant's
definitive Proxy Statement filed pursuant to Section 14(a) of the Securities
Exchange Act of 1934 and is incorporated herein by reference.


                                     PART IV

Item 14. Exhibits, Financial Statement Schedules, and Reports on Form 8-K


         (a)  1. Financial Statements

              The following consolidated financial statements of American
              Bancorp, Inc. and Subsidiary, included in pages 28 through 56 of
              the Registrant's Annual Report are incorporated by reference in
              Item 8:

                Consolidated Balance Sheets - December 31, 1999 and 1998
                Consolidated Statements of Income - Years Ended December 31,
                    1999, 1998 and 1997
                Consolidated Statements of Shareholders' Equity - Years
                    Ended December 31, 1999, 1998 and 1997
                Consolidated Statements of Cash Flows - Years Ended
                    December 31, 1999, 1998 and 1997
                Notes to Consolidated Financial Statements


         (a) 2. Financial Statement Schedules

              The Schedules to the consolidated financial statements required
              by Article 9, and all other schedules to the financial statements
              of the Registrant required by Article 9 of Regulation S-X are not
              required under the related instructions or are inapplicable and
              therefore have been omitted.


         (a) 3. Exhibits

              (13) 1999 Annual Report to Shareholders
              (22) Proxy Statement for Annual Meeting of Shareholders to be
                   held on April 12, 2000
              (23) Consent of Independent Auditors
              (27) Financial data schedule





                                     - 18 -

<PAGE>   19



Item 14. Exhibits, Financial Statement Schedules, and Reports on Form 8-K
        (continued)


         (b)       Reports on Form 8-K

             None


         (c)       Exhibits

                   The response to this portion of Item 14 is submitted as a
                   separate section of this report.


         (d)       Financial Statement Schedules

                   The response to this portion of Item 14 is submitted as a
                   separate section of this report.




                                     - 19 -

<PAGE>   20



                                   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.

                                       American Bancorp, Inc.
                                       (Registrant)



                                       By: /s/ Salvador L. Diesi, Sr.
                                          ------------------------------------
                                           Salvador L. Diesi, Sr., Chairman
                                           of the Board of the Company
                                           and the Bank; President of
                                           the Company and the Bank

                                       Date: March 08, 2000
                                            ----------------------------------


     Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed by the following persons on behalf of the Registrant and
in the capacities and on the dates indicated.



/s/ Salvador L. Diesi, Sr.                  /s/ Jasper J. Artall
------------------------------------        ----------------------------------
Salvador L. Diesi, Sr., Chairman of         Jasper J. Artall, Director
  the Board of the Company and the
  Bank; President of the Company
  and the Bank

Date: March 08, 2000                        Date: March 08, 2000
      ------------------------------             -----------------------------



/s/ Ronald J. Lashute                       /s/ Walter J. Champagne, Jr.
------------------------------------        -----------------------------------
Ronald J. Lashute, Executive Vice-          Walter J. Champagne, Jr., Director
  President and Chief Executive Officer
  of the Bank; Secretary/Treasurer of
  the Company

Date: March 08, 2000                        Date: March 08, 2000
      ------------------------------             -----------------------------


                                            /s/ J. C. Diesi
                                            ----------------------------------
                                            J. C. Diesi, Director

                                            Date: March 08, 2000
                                                  ----------------------------






                                     - 20 -

<PAGE>   21


                                  EXHIBIT INDEX


<TABLE>
<CAPTION>
Number                    Description
------            ----------------------------------
<S>               <C>
13.1              1999 Annual Report to shareholders
                  of American Bancorp, Inc.

22.1              1999 Proxy Statement for annual
                  meeting of shareholders.

23.1              Consent of Independent Auditors.

27.1              Financial Data Schedule.
</TABLE>




                                     - 21 -