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MFS(R)/SUN LIFE SERIES TRUST
High Yield Series
Supplement to the Current Statement of Additional Information
Certain investment limitations of the High Yield Series, as noted on
page 4 under the section entitled "Investment Techniques, Practices and Risks"
of MFS/Sun Life Series Trust's Statement of Additional Information dated May 1,
1999, are amended and restated as follows:
Percentage Limitations
(Based on Net Assets)
High Yield Series
Foreign Securities ............. 50%
Emerging Markets Securities .... 50%
The date of this Supplement is August 25, 1999.
