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MFS[RegTM] VARIABLE INSURANCE TRUSTSM
MFS EMERGING GROWTH SERIES MFS TOTAL RETURN SERIES
MFS RESEARCH SERIES MFS UTILITIES SERIES
Supplement dated May 1, 2000 to the Current Prospectus
This Supplement describes the series' service class shares, and it
supplements certain information in the series' Prospectus dated May 1,
2000. The caption headings used in this Supplement correspond with the
caption headings used in the Prospectus. All series described here may not
be available for purchase through your insurance contract. See your
insurance contract prospectus for a list of available investment products.
Service class shares were first offered for sale on May 1, 2000.
I EXPENSE SUMMARY
o Expense Table
The "Expense Table" describes the fees and expenses that you may pay when
you buy, redeem and hold service shares of each series. -
The table is supplemented as follows:
Annual Series Operating Expenses (expenses that are deducted from series'
assets):
<TABLE>
<CAPTION>
Emerging Total
Growth Research Return Utilities
Series Series Series Series
---------- ---------- ---------- ----------
<S> <C> <C> <C> <C>
Management Fees ................................. 0.75% 0.75% 0.75% 0.75%
Distribution (12b-1) Fees(1) .................... 0.20% 0.20% 0.20% 0.20%
Other Expenses(2) ............................... 0.09% 0.11% 0.15% 0.16%
---- ---- ---- ----
Total Annual Fund Operating Expenses(2) ......... 1.04% 1.06% 1.10% 1.11%
Fee Waiver/Expense Reimbursement(3) ............ N/A N/A N/A N/A
---- ---- ---- ----
Net Expenses(2) ................................ 1.04% 1.06% 1.10% 1.11%
---- ---- ---- ----
</TABLE>
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(1) Each series has adopted a distribution plan under Rule 12b-1 that
permits it to pay marketing and other fees to support the sale and
distribution of service class shares (these fees are referred to as
distribution fees).
(2) Each series has an expense offset arrangement that reduces the series'
custodian fee based upon the amount of cash maintained by the series with
its custodian and dividend disbursing agent. The series may enter into
other similar arrangements and directed brokerage arrangements, which
would also have the effect of reducing the series' expenses. "Other
Expenses" do not take into account these expense reductions, and are
therefore higher than the actual expenses of the series. Had these fee
reductions been taken into account, "Net Expenses" would be lower, and for
service class shares would be estimated to be:
1.03% for Emerging Growth Series 1.09% for Total Return Series
1.05% for Research Series 1.10% for Utilities Series
(3) MFS has contractually agreed, subject to reimbursement, to bear the
series' expenses such that "Other Expenses" (after taking into account the
expense offset arrangement described above) do not exceed 0.15% annually.
These contractual fee arrangements will continue until at least May 1,
2001, unless changed with the consent of the board of trustees which
oversees the series.
o Example of Expenses
The "Example of Expenses" table is intended to help you compare the cost
of investing in each series with the cost of investing in other mutual
funds.
The examples assume that:
o You invest $10,000 in the series for the time periods indicated and you
redeem your shares at the end of the time periods;
o Your investment has a 5% return each year and dividends and other
distributions are reinvested; and
o The series' operating expenses remain the same, except that the series'
total operating expenses are assumed to be the series' "Net Expenses" for
the first year, and the series' "Total Annual Fund Operating Expenses"
for subsequent years (see Expense Table).
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The table is supplemented as follows:
<TABLE>
<CAPTION>
Service Class Shares Year 1 Year 3
--------------------------- ------------ -----------
<S> <C> <C>
Emerging Growth Series $106 $331
Research Series 108 337
Total Return Series 112 350
Utilities Series 113 353
</TABLE>
II DISTRIBUTION FEES
Each series has adopted a plan under Rule 12b-1 that permits it to pay
marketing and other fees to support the sale and distribution of service
class shares. These annual distribution fees may equal up to 0.25%, and are
paid out of the assets of each series' service class shares. Over time,
these fees will increase the cost of your shares and may cost you more than
paying other types of sales charges. Currently, the distribution fee is
0.20% of each series' service class shares. The remaining 0.05% service
class distribution fee is not being imposed and will be imposed only with
the approval of the Trustees of the Trust.
The date of this Supplement is May 1, 2000
