<PAGE>
ALLMERICA FINANCIAL LIFE INSURANCE AND ANNUITY COMPANY
SUPPLEMENT TO PROSPECTUS DATED MAY 1, 1999
THIS SUPPLEMENT SUPPLANTS THE SUPPLEMENT DATED SEPTEMBER 1, 1999
VEL III ACCOUNT
* * *
Effective December 1, 1999, the following information relating to the Guaranteed
Death Benefit Rider is amended as follows:
Under THE CONTRACT, the following sub-heading on page 24 of the Prospectus is
amended in its entirety as follows:
"GUARANTEED DEATH BENEFIT RIDER (NOT AVAILABLE IN CERTAIN STATES, INCLUDING
MASSACHUSETTS)."
Under APPENDIX B - OPTIONAL INSURANCE BENEFITS on page B-1 of the Prospectus,
the following sentence is inserted at the end of the paragraph under GUARANTEED
DEATH BENEFIT RIDER
"This rider is not available in certain states, including Massachusetts."
* * *
Effective September 1, 1999, the following information relating to the Select
Aggressive Growth Fund and Select Capital Appreciation Fund is amended as
follows:
Under the SUMMARY - CHARGES OF THE UNDERLYING FUNDS, the table and footnotes are
amended as follows:
<TABLE>
<CAPTION>
MANAGEMENT FEE OTHER EXPENSES TOTAL FUND EXPENSES
(AFTER VOLUNTARY (AFTER APPLICABLE (AFTER WAIVERS/
UNDERLYING FUND WAIVERS) REIMBURSEMENTS) REIMBURSEMENTS)
- --------------- -------- --------------- ---------------
<S> <C> <C> <C>
Select Aggressive Growth Fund................... 0.82%*** 0.07% 0.89%(1)(2)***
Select Capital Appreciation Fund................ 0.94%*** 0.10% 1.04%(1)(2)***
</TABLE>
*** Effective September 1, 1999, the management fee rates for the Select
Aggressive Growth Fund and Select Capital Appreciation Fund were revised.
The Management Fee and Total Fund Expenses shown in the table above have
been adjusted to assume that the revised rates took effect on January 1,
1998.
Under footnote (2), the percentage for the Select Aggressive Growth Fund is
changed to 0.86%.
Under INVESTMENT ADVISORY SERVICES-the management fee schedule for the Select
Aggressive Growth Fund and Select Capital Appreciation Fund is amended as
follows:
<TABLE>
<S> <C> <C>
Select Aggressive Growth Fund First $100 Million 1.00%
Next $150 Million 0.90%
Next $250 Million 0.80%
Next $500 Million 0.70%
<PAGE>
<S> <C> <C>
Select Capital Appreciation Fund First $100 Million 1.00%
Next $150 Million 0.90%
Next $250 Million 0.80%
Next $500 Million 0.70%
Over $1 Billion 0.65%
</TABLE>
SUPPLEMENT DATED DECEMBER 1, 1999
