<PAGE>
MFS/SUN LIFE SERIES TRUST- FOREIGN & COLONIAL EMERGING MARKETS EQUITY SERIES
Supplement to the Current Prospectus
The description of the portfolio manager under the "Management of the Series
Fund - Investment Adviser" section beginning on page 48 is hereby revised to
reflect that, effective February 1, 1997, Jeffery Chowdhry is an additional
portfolio manager of the Series. Mr. Chowdhry, a Director of Foreign & Colonial
Emerging Markets LTD ("FCEM"), has been employed by FCEM as a portfolio manager
since 1994. Prior to 1994, Mr. Chowdhry was a portfolio manager at BZW
Investment Management.
The date of this Supplement is January 29, 1997.
<PAGE>
MFS/FOREIGN & COLONIAL EMERGING MARKETS EQUITY FUND
MFS WORLD GROWTH FUND
Supplement to the Current Prospectus
The description of the portfolio manager under the "Management of the Fund
Investment Adviser" section of the Prospectus is hereby revised to reflect that,
effective February 1, 1997, Jeffery Chowdhry is an additional portfolio manager
of the Fund. Mr. Chowdhry, a Director of Foreign & Colonial Emerging Markets LTD
("FCEM"), has been employed by FCEM as a portfolio manager since 1994. Prior to
1994, Mr. Chowdhry was a portfolio manager at BZW Investment Management.
The date of this Supplement is January 29, 1997.
<PAGE>
MFS/SUN LIFE SERIES TRUST- GOVERNMENT SECURITIES SERIES
Supplement to the Current Prospectus
The description of the portfolio manager under the "Management of the Series
Fund - Investment Adviser" section beginning on page 48 is hereby revised to
reflect that, effective January 1, 1997, D. Richard Smith is the portfolio
manager of the Series. Mr. Smith, a Vice President of Massachusetts Financial
Services Company (the "Adviser"), has been employed by the Adviser as a
portfolio manager since 1993. Prior to 1993, Mr. Smith was a portfolio manager
at Salomon Brothers, Inc.
The date of this Supplement is January 29, 1997.
