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MFS SERIES TRUST I
500 Boylston Street Boston Massachusetts 02116-3741
617 954 5000
January 5, 1998
VIA EDGAR
Securities and Exchange Commission
Judiciary Plaza
450 Fifth Street, NW
Washington, DC 20549
Re: MFS Series Trust I (the "Trust") (File No. 33-7638) on Behalf of:
MFS Managed Sectors Fund
MFS Cash Reserve Fund
MFS World Asset Allocation Fund
MFS Equity Income Fund
MFS Research Growth and Income Fund
MFS Core Growth Fund
MFS Strategic Growth Fund
MFS Special Opportunities Fund
MFS Convertible Securities Fund
MFS Blue Chip Fund
MFS New Discovery Fund
MFS Science and Technology Fund and
MFS Research International Fund
Ladies and Gentlemen:
Pursuant to Rule 497(j) under the Securities Act of 1933, as amended,
please accept this letter as certification that the Prospectuses and Statements
of Additional Information for the Trust do not differ from those contained in
Post-Effective Amendment No. 29 (the "Amendment") to the Trust's Registration
Statement on Form N-1A. The Amendment was filed electronically on December 24,
1997.
Please call the undersigned or Sharon Julius-Doucette at(617) 954-5406
or (800) 343-2829 with any questions you may have.
Very truly yours,
JAMES R. BORDEWICK, JR.
James R. Bordewick, Jr.
Assistant Secretary
JRB/bjn
