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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON DC 20549
 
                            ------------------------
 
                                   FORM 10-K
 
(MARK ONE)
/X/ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT
    OF 1934 [FEE REQUIRED]
 
    FOR THE FISCAL YEAR ENDED DECEMBER 31, 1998
 
                                       OR
 
/ / TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
    ACT OF 1934 [NO FEE REQUIRED]
 
FOR THE TRANSITION PERIOD FROM        COMMISSION FILE NUMBER
                                             33-71690
 
                            ------------------------
 
                      FIRST FORTIS LIFE INSURANCE COMPANY
             (Exact name of registrant as specified in its charter)
 
<TABLE>
<S>                                   <C>
              NEW YORK                      13-2699219
   State or other jurisdiction of         (IRS Employer
   incorporation or organization       Identification No.)
 
 220 SALINA MEADOWS PARKWAY, SUITE
                255,
      SYRACUSE, NEW YORK 13212
  (Address of principal executive
              offices)
</TABLE>
 
                 Registrant's telephone number: (315) 451-0066
 
                            ------------------------
 
        SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT: NONE
 
        SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT: NONE
 
                            ------------------------
 
    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.
 
                      /X/  Yes                      / /  No
 
                      DOCUMENTS INCORPORATED BY REFERENCE
 
    Portions of the Form S-2 Amended Registration Statement to be filed by the
Registrant are incorporated by reference into Parts I, II and III.
 
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<PAGE>
                                     PART I
 
ITEM 1.  BUSINESS
 
    "First Fortis Life Insurance Company" on page 8 and "Further Information
About First Fortis" on page 21 of the prospectus attached hereto as Exhibit No.
99 are incorporated herein.
 
    The Company seeks to compete primarily on the basis of customer service,
product design, and, in the case of products funded through Fortis Series Fund,
Inc., the investment results achieved by Fortis Advisers, Inc. Many other
insurance companies compete with the Company in each of its markets, including
on the basis of price. Many of these companies, which include some of the
largest and best known insurance companies, have considerably greater resources
than the Company.
 
ITEM 2.  PROPERTIES
 
    The Company leases its home office building, consisting of 26,875 square
feet, in Syracuse, New York. It also leases space consisting of 9,471 square
feet for the maintenance of a sales office located in New York City and space
consisting of 2,539 square feet for a sales office in Rochester, NY. The Company
expects that this office space will be adequate for the foreseeable future.
 
ITEM 3.  LEGAL PROCEEDINGS
 
    The Company is a defendant in various lawsuits, none of which, in the
opinion of the Company counsel, will result in a material liability.
 
ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS
 
    Not Applicable.
<PAGE>
                                    PART II
 
ITEM 5.  MARKET FOR REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDER MATTERS
 
    Not applicable.
 
ITEM 6.  SELECTED FINANCIAL DATA
 
    "Selected Financial Data" from page 21 of the prospectus attached hereto as
Exhibit No. 99, is incorporated herein by reference.
 
ITEM 7.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
         OF OPERATIONS
 
    "Management's Discussion and Analysis of Financial Condition and Results of
Operations" on page 21 through 23 of the prospectus attached hereto as Exhibit
No. 99 is incorporated herein by reference.
 
ITEM 7A.  QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.
 
    The matters set forth under the caption "Market Risk and Risk Management" in
Management's Discussion and Analysis of Results of Operations (Item 7 of this
report) are incorporated herein by reference.
 
ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA
 
    The Company's financial statements included in the prospectus attached
hereto as Exhibit No. 99 are incorporated by reference.
 
ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
         FINANCIAL DISCLOSURE
 
    None.
<PAGE>
                                    PART III
 
ITEM 10.  DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT
 
<TABLE>
<CAPTION>
<S>                         <C>
 
Zafar Rashid, 49            President and Chief Executive Officer; Senior Vice President and
Director since 1998          Chief Financial Officer of Fortis Inc.
Larry M. Cains, 52          Treasurer; Senior Vice President of Fortis, Inc.
Director since 1995
Allen R. Freedman, 59       Chairman of Board; Chairman and Chief Executive Officer of
Director Since 1989          Fortis, Inc.
Dean C. Kopperud, 46        Chief Executive Officer of Fortis Advisers, Inc. and President of
Director Since 1994          Fortis Investors, Inc.; Executive Vice President -- Fortis
                             Financial Group of Fortis Benefits Insurance Company
Terry J. Kryshak, 48        Senior Vice President and Chief Administrative Officer
Director Since 1991
Susie Gharib, 48            Anchorwoman, Cable NBC; before that, Anchorwoman, Financial News
Director Since 1991          Network
Dale Edward Gardner, 68     President, Gardner & Bull
Director Since 1989
Kenneth W. Nelson, 77       President, Tech Products, Inc.
Director Since 1989
Clarence Elkus Galston, 89  Attorney at Law
Director Since 1989
Robert B. Pollock, 44       President and Chief Executive Officer of Fortis Benefits
Director Since 1995          Insurance Company
Barbara R. Hege, 55         Assistant Treasurer and Chief Financial Officer
Jerome A. Atkinson, 49      Secretary; Vice President, Secretary and General Counsel of
                             Fortis, Inc.; before that Senior Vice President, Secretary and
                             General Counsel of American Security Insurance Company
</TABLE>
 
    First Fortis' officers serve at the pleasure of the Board of Directors, and
members of the Board who are also officers or employees of First Fortis serve
without compensation. All Directors serve until their successors are duly
elected and qualified. The compensation of members of the Board who are not also
officers or employees of First Fortis or its affiliates is as follows. The
Director receives $1,000 for attendance at the annual Board meeting. If the
Director is also a member of the Audit Committee and/or the Investment
Committee, the Director also receives $1,000 for attending any meeting of such
committee unless the committee meeting date is the same as the annual meeting,
in which case the committee meeting compensation is $500.
 
    Mr. Freedman is also a director of Systems and Computer Technology
Corporation and the following registered investment companies: Fortis Equity
Portfolios, Inc.; Fortis Growth Fund, Inc.; Fortis Income Portfolios, Inc.;
Fortis Securities, Inc.; Fortis Tax-Free Portfolios, Inc.; Fortis Money
Portfolios, Inc.; Fortis Advantage Portfolios, Inc.; Fortis Worldwide
Portfolios, Inc.; Fortis Series Fund, Inc.; Special Portfolios, Inc.
<PAGE>
ITEM 11.  EXECUTIVE COMPENSATION
  SUMMARY COMPENSATION TABLE
 
<TABLE>
<CAPTION>
                                                                       ANNUAL COMPENSATION
                                                            -----------------------------------------
                                                                                      OTHER ANNUAL         ALL OTHER
                                                              SALARY       BONUS      COMPENSATION     COMPENSATION (1)
NAME AND PRINCIPAL POSITION                        YEAR         ($)         ($)            ($)                ($)
-----------------------------------------------  ---------  -----------  ---------  -----------------  -----------------
<S>                                              <C>        <C>          <C>        <C>                <C>
Zafar Rashid...................................       1998  $         0  $       0      $       0          $       0
  President                                           1997            0          0              0                  0
Terry J. Kryshak...............................       1998  $   117,300  $  37,000      $       0          $   9,258
  Senior Vice President and                           1997      115,000     34,000              0              8,940
  Chief Administrative Officer                        1996      111,000     34,000              0              6,660
</TABLE>
 
(1) This column includes contributions made by First Fortis for the year for the
    benefit for the named individual to defined contribution retirement plans.
 
    As additional compensation to its employees and executive officers, First
Fortis has an Employees' Uniform Retirement Plan and an Executive Retirement
Plan which generally provide an annual annuity benefit upon retirement at age 65
(or a reduced benefit upon early retirement) equal to: .9% of the employee's
Average Annual compensation up to the employee's social security covered
compensation, plus 1.3% of Average Annual compensation above the employee's
social security covered compensation up to $235,840, as adjusted by an index,
multiplied by the employee's years of credited services.
 
    The following table illustrates the combined estimated life annuity benefit
payable from the Employees Uniform Retirement Plan and the Executive Retirement
Plan to employees with the specified Final Average Salary and Years of Service
upon retirement.
 
PENSION TABLE
 
<TABLE>
<CAPTION>
        1998                                   YEARS OF SERVICE
      EARNINGS            10         15         20         25         30         35
<S>                    <C>        <C>        <C>        <C>        <C>        <C>
      125,000             15,005     22,507     30,010     37,512     45,015     52,517
      150,000             18,255     27,382     36,510     45,637     54,765     63,892
      175,000             21,505     32,257     43,010     53,762     64,515     75,267
      200,000             24,755     37,132     49,510     61,887     74,265     86,642
      225,000             28,005     42,007     56,010     70,012     84,015     98,017
      250,000             30,990     46,485     61,980     77,475     92,970    108,465
      275,000 +           31,908     47,862     63,816     79,770     95,724    111,678
</TABLE>
 
    The table above excludes social security benefits. In general, for the
purposes of these plans compensation includes salary and bonuses. The credited
years of service with First Fortis for those individuals named in the Summary
Compensation Table above are as follows: 1 and 8.
 
ITEM 12.  SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT
 
    (a) Security Ownership of Certain Beneficial Owners
 
<TABLE>
<CAPTION>
                                                          PERCENTAGE
                                          NUMBER OF     OF OUTSTANDING
  NAME & ADDRESS OF BENEFICIAL OWNER       SHARES       VOTING SHARES
---------------------------------------  -----------  ------------------
<S>                                      <C>          <C>
Fortis, Inc.                                100,000          100%
 One Chase Manhattan Plaza
 New York, NY 10005
</TABLE>
 
<PAGE>
    (b) Security Ownership of Management
 
    None.
 
    (c) Changes in Control
 
    None.
 
ITEM 13.  CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS
 
    None.
<PAGE>
                                    PART IV
 
ITEM 14.  EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K
 
(a)(1)The following financial statements of First Fortis Life Insurance Company
      are included in Item 8:
 
       Report of Independent Auditors
 
       Balance Sheets at December 31, 1998 and 1997
 
       Statements of Operations for the years ended December 31, 1998, 1997 and
       1996
 
       Statements of Changes in Shareholder's Equity for the years ended
       December 31, 1998, 1997 and 1996
 
       Statements of Cash Flows for the years ended December 31, 1998, 1997 and
       1996.
 
       Notes to Financial Statements
 
(a)(2) The information required by the following financial statement schedules
       for First Fortis Life Insurance Company are included in Item 8:
 
       I.  Summary of Investments -- Other than Investments in Related Parties
           -- Contained in the Notes to Financial Statements.
 
       II. Condensed Financial Information of Registrant -- Contained in the
           non-financial statement part of the prospectus.
 
       III. Supplementary Insurance Information -- Contained in Financials and
            Notes to Financial Statements.
 
       IV. Reinsurance -- Contained in the Notes to Financial Statements.
 
       V.  Valuation and Qualifying Accounts -- Contained in the Financial
           Statements and Notes to Financial Statements.
 
    All other schedules to the financial statements required by Article 7 of the
Regulation S-X are not required under the related instructions or are
inapplicable and therefore have been omitted.
 
(a)(3) Listing of Exhibits
 
       2. None.
 
       3.(a) Articles of Incorporation of First Fortis Life Insurance Company --
       Incorporated by reference from Form 10-K filed by registrant, File No.
       33-71690, on March 29, 1996.
 
        (b) By-laws of First Fortis Life Insurance Company (Incorporated by
       reference from Form N-4 Registration Statement, File No. 33-71686, of
       registrant and its Separate Account A filed on November 15, 1993);
 
       4.(a) Form of Combination Fixed and Variable Group Annuity Contract;
       (Incorporated by reference from Post-Effective Amendment No. 2 to Form
       N-4 Registration Statement, File No. 33-71686, of registrant and its
       Separate Account A filed on April 27, 1995);
 
        (b) Form of Application to be used in connection with Contract filed as
       Exhibit 4 (a) (Incorporated by reference from Post-Effective Amendment
       No. 2 to Form N-4 Registration Statement, File No. 33-71686, of
       registrant and its Separate Account A filed on April 27, 1995);
 
        (c) Form of IRA Endorsement (Incorporated by reference from
       Post-Effective Amendment No. 2 to Form N-4 Registration Statement, File
       No. 33-71686, of registrant and its Separate Account A filed on April 27,
       1995);
 
        (d) Form of Section 403(b) Annuity Endorsement (Incorporated by
       reference from Post-Effective Amendment No. 2 to Form N-4 Registration
       Statement, File No. 33-71686, of registrant and its Separate Account A
       filed on April 27, 1995);
<PAGE>
       10. Administrative Service Agreement -- Incorporated by reference from
       Form 10-K filed by registrant, File No. 33-71690, on March 29, 1996.
 
       24.(a) Power of Attorney for Messrs. Rutherford, Freedman and Madame
       Gharib. (Incorporated by reference from Form N-4 Registration Statement,
       File No. 33-71686, of registrant and its Separate Account A filed on
       November 15, 1993).
 
        (b) Power of Attorney for Messrs. Gardner, Nelson and Galston.
       (Incorporated by reference from Form N-4 Registration Statement, File No.
       33-71686, of registrant and its Separate Account A filed on February 28,
       1995.)
 
       99. Form of prospectus to be filed as part of Form S-2 Amended
       Registration Statement of the Registrant.
 
(b)    Reports on Form 8-K filed in the fourth quarter of 1998
 
       None.
 
(c)    Exhibits
 
       Included in 14 (a)(3) above.
 
(d)    Financial Statement Schedules
 
       Included in 14(a)(2) above.
<PAGE>
                                   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 on this 26th day of
March, 1999.
 
                                          FIRST FORTIS LIFE INSURANCE COMPANY
                                          By:     /s/     ZAFAR RASHID
                                             -----------------------------------
                                                        Zafar Rashid
                                             PRESIDENT & CHIEF EXECUTIVE OFFICER
                                                (PRINCIPAL EXECUTIVE OFFICER)
 
    Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been duly signed below by the following persons on behalf of the
registrant and in the capacities indicated on the 26th day of March, 1999. The
following persons represent a majority of the Board of Directors of First Fortis
Life Insurance Company:
 
<TABLE>
<CAPTION>
                       SIGNATURE                                          TITLE WITH FIRST FORTIS
--------------------------------------------------------  --------------------------------------------------------
 
<C>                                                       <S>
                      /s/     ZAFAR RASHID
      --------------------------------------------        President, Chief Executive Officer and Director
                      Zafar Rashid                         (Principal Executive Officer)
 
                     /s/   TERRY J. KRYSHAK
      --------------------------------------------        Sr. Vice President and Chief Administrative Officer and
                    Terry J. Kryshak                       Director
 
                     /s/    LARRY M. CAINS
      --------------------------------------------        Treasurer and Director (Principal Financial Officer)
                     Larry M. Cains
 
                     /s/   BARBARA R. HEGE
      --------------------------------------------        Chief Financial Officer
                    Barbara R. Hege
 
                           *
      --------------------------------------------        Chairman of Board and Director
                  Allen Royal Freedman
 
                           *
      --------------------------------------------        Director
                      Susie Gharib
 
                           *
      --------------------------------------------        Director
                  Dale Edward Gardner
 
                           *
      --------------------------------------------        Director
                 Kenneth Warwick Nelson
 
                     /s/  ROBERT B. POLLOCK
      --------------------------------------------        Director
                   Robert B. Pollock
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
                       SIGNATURE                                          TITLE WITH FIRST FORTIS
--------------------------------------------------------  --------------------------------------------------------
 
<C>                                                       <S>
                     /s/   DEAN C. KOPPERUD
      --------------------------------------------        Director
                    Dean C. Kopperud
 
                           *
      --------------------------------------------        Director
                 Clarence Elkus Galston
 
            *By /s/         TERRY J. KRYSHAK
      --------------------------------------------
                    Terry J. Kryshak
                    ATTORNEY-IN-FACT
</TABLE>