<PAGE>
SUPPLEMENT DATED SEPTEMBER 23, 1998, TO
THE PROSPECTUS DATED MAY 1, 1998
EXCHEQUER VARIABLE ANNUITY
A FLEXIBLE PREMIUM DEFERRED COMBINATION
FIXED AND VARIABLE ANNUITY CONTRACT
ISSUED BY
SECURITY LIFE OF DENVER INSURANCE COMPANY
AND
SECURITY LIFE SEPARATE ACCOUNT A1
THIS SUPPLEMENT UPDATES CERTAIN INFORMATION CONTAINED IN YOUR PROSPECTUS.
PLEASE READ IT CAREFULLY AND KEEP IT WITH YOUR PROSPECTUS FOR FUTURE REFERENCE.
Effective July 6, 1998, INVESCO Funds Group, Inc. ("IFG"), the investment
adviser to INVESCO Variable Investment Funds, Inc., changed the arrangements by
which it voluntarily absorbs certain expenses of the INVESCO VIF - Industrial
Income Fund, INVESCO VIF - High Yield Fund and INVESCO VIF - Utilities Fund.
See Pages 9 - 11 of the prospectus. The annual expenses of these Portfolios,
restated to reflect these changes, are as follows:
PORTFOLIO INVESTMENT OTHER EXPENSES TOTAL
MANAGEMENT PORTFOLIO
FEE EXPENSES
========================================================================
INVESCO VIF - High 0.60% 0.45% 1.05%
Yield Fund
INVESCO VIF - 0.75% 0.30% 1.05%
Industrial Income Fund
INVESCO VIF - 0.60% 0.55% 1.15%
Utilities Portfolio
* * *
The examples depicting the dollar amount of expenses on Page 12 are changed as
follows:
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<CAPTION>
IF YOU SURRENDERED YOUR IF YOU DO NOT SURRENDER YOUR
CONTRACT AT THE END OF THE CONTRACT OR IF YOU ANNUITIZE AT
STATED PERIOD. THE END OF THE STATED PERIOD.
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<S> <C> <C> <C> <C> <C> <C> <C> <C>
1 3 5 10 1 3 5 10
DIVISION INVESTING IN: Year Years Years Years Year Years Years Years
- -------------------------------------------------------------------------------------------------------------------------------
INVESCO Variable Investment Funds, Inc.
INVESCO VIF - High Yield Portfolio 97 131 169 293 27 81 139 293
INVESCO VIF - Industrial Income Portfolio 97 131 169 293 27 81 139 293
INVESCO VIF - Utilities Portfolio 98 134 173 303 28 84 143 303
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