<PAGE>
Rule 424(b)(3)
File No. 333-77041
SUPPLEMENT DATED DECEMBER 20, 1999
TO
PROFILE DATED MAY 1, 1999
AND
PROSPECTUS DATED MAY 1, 1999
FOR
MFS REGATTA PLATINUM
VARIABLE AND FIXED ANNUITY
ISSUED BY SUN LIFE ASSURANCE COMPANY OF CANADA (U.S.)
THE FOLLOWING LANGUAGE APPLIES ONLY TO CONTRACTS ISSUED TO OR HELD BY
PARTICIPANTS RESIDENT OR DOMICILED IN PUERTO RICO:
Section 6, Taxes, of the Profile is hereby deleted with respect to
Contracts issued in Puerto Rico and is hereby replaced by the following:
"Under the tax laws of Puerto Rico, when an annuity
payment is made under your Contract, your Annuitant or any
other Payee is required to include as gross income the portion
of each annuity payment equal to 3% of the aggregate purchase
payments you made under the Contract. The amount if any, in
excess of the included amount is excluded from gross income.
After an amount equal to the aggregate amount excluded from
gross income has been received, all of the annuity payments
are considered to be taxable income. You should consult with
your tax adviser for specific tax information."
The section of the Prospectus entitled "Federal Tax Status" is hereby
amended by the addition of the following sub-section:
"PUERTO RICO TAX CONSIDERATIONS ON VARIABLE ANNUITY CONTRACTS
The Contract offered by this Prospectus is considered
an annuity contract under Section 1022 of the Puerto Rico
Internal Revenue Code of 1994, as amended (the "1994 Code").
Under the current provisions of the 1994 Code, no income tax
is payable on increases in value of accumulation shares of
annuity units credited to a variable annuity contract until
payments are made to the annuitant or other payee under such
contract.
If any annuity distributions are made under an
annuity contract, the annuitant or other payee will be
required to include as gross income the portion of each
payment equal to 3% of the aggregate premiums or other
consideration paid for the annuity. The amount, if any, in
excess of the included amount is excluded from gross income.
After an amount equal to the aggregate amount excluded from
gross income has been received, all of the annuity payments
are considered to be taxable income.
In the event payment under a Contract is made in a
lump sum, the amount of the payment would be included in the
gross income of the Annuitant or other Payee to the extent of
the Annuitant's aggregate premiums or other consideration
paid.
The provisions of the 1994 Code with respect to
qualified retirement plans described in this Prospectus vary
significantly from those under the Internal Revenue Code.
Although we
<PAGE>
currently offer the Contract in Puerto Rico in connection with
qualified retirement plans, the text of this Prospectus under
the heading "Federal Tax Status" dealing with such qualified
retirement plans is inapplicable to Puerto Rico and should be
disregarded.
For information regarding the income tax consequences
of owning a Contract, you should consult a qualified tax
adviser."
THIS SUPPLEMENT IS NOT VALID UNLESS ACCOMPANIED OR PRECEDED BY THE CURRENT
PROSPECTUS OF MFS REGATTA PLATINUM VARIABLE AND FIXED ANNUITY, DATED MAY 1,
1999, AND THE CURRENT PROSPECTUS OF THE MFS/SUN LIFE SERIES TRUST. THIS
SUPPLEMENT AND THE PROSPECTUSES SHOULD BE READ AND RETAINED FOR FURTHER
REFERENCE.
PLAT-16PR 12/99
<PAGE>
Rule 424(b)(3)
File No. 333-77041
SUPPLEMENT DATED DECEMBER 20, 1999
TO
PROFILE DATED MAY 1, 1999
AND
PROSPECTUS DATED MAY 1, 1999
FOR
FUTURITY II
VARIABLE AND FIXED ANNUITY
ISSUED BY SUN LIFE ASSURANCE COMPANY OF CANADA (U.S.)
THE FOLLOWING LANGUAGE APPLIES ONLY TO CONTRACTS ISSUED TO OR HELD BY
PARTICIPANTS RESIDENT OR DOMICILED IN PUERTO RICO:
Section 6, Taxes, of the Profile is hereby deleted with respect to
Contracts issued in Puerto Rico and is hereby replaced by the following:
"Under the tax laws of Puerto Rico, when an annuity
payment is made under your Contract, your Annuitant or any
other Payee is required to include as gross income the portion
of each annuity payment equal to 3% of the aggregate purchase
payments you made under the Contract. The amount if any, in
excess of the included amount is excluded from gross income.
After an amount equal to the aggregate amount excluded from
gross income has been received, all of the annuity payments
are considered to be taxable income. You should consult with
your tax adviser for specific tax information."
The section of the Prospectus entitled "Federal Tax Status" is hereby
amended by the addition of the following sub-section:
"PUERTO RICO TAX CONSIDERATIONS ON VARIABLE ANNUITY CONTRACTS
The Contract offered by this Prospectus is considered
an annuity contract under Section 1022 of the Puerto Rico
Internal Revenue Code of 1994, as amended (the "1994 Code").
Under the current provisions of the 1994 Code, no income tax
is payable on increases in value of accumulation shares of
annuity units credited to a variable annuity contract until
payments are made to the annuitant or other payee under such
contract.
If any annuity distributions are made under an
annuity contract, the annuitant or other payee will be
required to include as gross income the portion of each
payment equal to 3% of the aggregate premiums or other
consideration paid for the annuity. The amount, if any, in
excess of the included amount is excluded from gross income.
After an amount equal to the aggregate amount excluded from
gross income has been received, all of the annuity payments
are considered to be taxable income.
In the event payment under a Contract is made in a
lump sum, the amount of the payment would be included in the
gross income of the Annuitant or other Payee to the extent of
the Annuitant's aggregate premiums or other consideration
paid.
The provisions of the 1994 Code with respect to
qualified retirement plans described in this Prospectus vary
significantly from those under the Internal Revenue Code.
Although we
<PAGE>
currently offer the Contract in Puerto Rico in connection with
qualified retirement plans, the text of this Prospectus under
the heading "Federal Tax Status" dealing with such qualified
retirement plans is inapplicable to Puerto Rico and should be
disregarded.
For information regarding the income tax consequences
of owning a Contract, you should consult a qualified tax
adviser."
THIS SUPPLEMENT IS NOT VALID UNLESS ACCOMPANIED OR PRECEDED BY THE CURRENT
PROSPECTUS OF FUTURITY II VARIABLE AND FIXED ANNUITY, DATED MAY 1, 1999, AND THE
CURRENT PROSPECTUSES OF THE FUNDS. THIS SUPPLEMENT AND THE PROSPECTUSES SHOULD
BE READ AND RETAINED FOR FURTHER REFERENCE.
FUT 801
