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MFS SERIES TRUST X
500 Boylston Street Boston Massachusetts 02116-3741
617 954 5000
October 1, 1998
VIA EDGAR
Securities and Exchange Commission
Judiciary Plaza
450 Fifth Street, NW
Washington, DC 20549
Re: MFS Series Trust X (the "Trust") (File Nos. 33-1657 and 811-4492)
on behalf of MFS International Growth Fund, MFS International
Growth and Income Fund and MFS/Foreign & Colonial Emerging Markets
Equity 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 Prospectus and Statement of
Additional Information for the Trust do not differ from those contained in
Post-Effective Amendment No. 23 (the "Amendment") to the Trust's Registration
Statement on Form N-1A. The Amendment was filed electronically on September 25,
1998.
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
