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MASSACHUSETTS FINANCIAL SERVICES COMPANY
500 BOYLSTON STREET, BOSTON, MASSACHUSETTS 02116-3741
(617) 954-5000
June 19, 2000
VIA EDGAR
Securities and Exchange Commission
Judiciary Plaza
450 Fifth Street, NW
Washington, DC 20549
Re: MFS(R)/Sun Life Series Trust (the "Trust") (File Nos. 2-83616 and
811-3732) on behalf of MFS(R)Technology Series
Ladies and Gentlemen:
Pursuant to Rule 497(j) under the Securities Act of 1933, as amended,
please accept this letter as certification that the Prospectus and Statement of
Additional Information for the Trust do not differ from those contained in
Post-Effective Amendment No. 26 (the "Amendment") to the Trust's Registration
Statement on Form N-1A. The Amendment was filed electronically on May 1, 2000
under Rule 485(a) and, as confirmed by Keith Carpenter of the staff of the
Securities and Exchange Commission, granted accelerated effectiveness on June
14, 2000.
Please call the undersigned or Karen M. Ray at (617) 954-5801 or (800)
343-2829 with any questions you may have.
Very truly yours,
JAMES F. DESMARAIS
James F. DesMarais
Assistant General Counsel
JFD/bjn
