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MFS SERIES TRUST I
500 Boylston Street Boston Massachusetts 02116-3741
617 954 5000
December 30, 1996
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 Research Growth and Income Fund, MFS
Equity Income Fund, MFS Core Growth Fund, MFS Aggressive 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 (series of
MFS Series Trust I)
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 does not differ from that contained in
Post-Effective Amendment No. 27 (the "Amendment") to the Trust's Registration
Statement on Form N-1A. This Amendment was filed electronically on December 27,
1996.
Please call the undersigned or Sharon Julius-Doucette at (617) 954-5000
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
