<PAGE>
SEPARATE ACCOUNT VA-K
(VALUPLUS ASSURANCE VARIABLE IMMEDIATE ANNUITY)
ALLMERICA FINANCIAL LIFE INSURANCE AND ANNUITY COMPANY
FIRST ALLMERICA FINANCIAL LIFE INSURANCE COMPANY
SUPPLEMENT DATED DECEMBER 31, 2000 TO PROSPECTUS DATED MAY 2000
***
The Dreyfus Socially Responsible Growth Fund of the Dreyfus Socially Responsible
Growth Fund, Inc., the Dreyfus VIF Appreciation Portfolio of Dreyfus Variable
Investment Fund, and the Dreyfus VIF Quality Bond Portfolio of Dreyfus Variable
Investment Fund each offer two classes of shares: Service shares and Initial
shares. Each Fund's prospectus dated December 31, 2000 describes the Service
shares and the Initial shares. Currently, only the Funds' Initial shares are
available for investment under the Contracts.
***
SUPPLEMENT DATED DECEMBER 31, 2000
