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MFS(R) SUN LIFE SERIES TRUST
MFS(R) Total Return Series
Supplement to the Current Prospectus
The description of portfolio managers under the "Management of the Series -
Investment Adviser" section is hereby restated as follows:
Total Return Series - David M. Calabro, a Senior Vice President of MFS,
has been a portfolio manager of the Series since July 19, 1995 and
employed by the Adviser as a portfolio manager since 1992. Mr. Calabro
is the head of this portfolio management team and a manager of the
common stock portion of the Series' portfolio. Geoffrey L. Kurinsky, a
Senior Vice President of MFS, has been a portfolio manager of the
Series since July 19, 1995 and employed by the adviser as a portfolio
manager since 1987. Mr. Kurinsky is the manager of the Series' fixed
income securities. Constantinos G. Mokas, a Vice President of MFS, has
been a portfolio manager of the Series since April 1, 1998, and has
been employed by the Adviser as a portfolio manager since 1990. Mr.
Mokas is the manager of the Series' convertible securities. Lisa B.
Nurme, a Senior Vice President of MFS, has been employed by the Adviser
as a portfolio manager since 1987. Ms. Nurme is a manager of the common
stock portion of the Series' portfolio and has been a portfolio manager
of the Series since July 19, 1995. Maura A. Shaughnessy, a Senior Vice
President of MFS, has been employed by the Adviser as a portfolio
manager since 1991 and has been a portfolio manager of the Series since
July 19, 1995. Ms. Shaughnessy is a manager of the common stock portion
of the Series' portfolio. Kenneth J. Enright, a Vice President of MFS,
has been employed by the Adviser as a portfolio manager since 1986 and
has been a portfolio manager of the Series since January 15, 1999. Mr.
Enright is a manager of the common stock portion of the Series'
portfolio.
The date of this Supplement is January 15, 1999.
