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MFS SERIES TRUST IX
500 Boylston Street Boston Massachusetts 02116-3741
617 954 5000
August 31, 1998
VIA EDGAR
Securities and Exchange Commission
Judiciary Plaza
450 Fifth Street, NW
Washington, DC 20549
Re: MFS Series Trust IX (the "Trust") (File Nos. 2-50409 and 811-2464)
on behalf of MFS Bond Fund, MFS Limited Maturity Fund and MFS
Municipal Limited Maturity 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. 35 (the "Amendment") to the Trust's Registration
Statement on Form N-1A. The Amendment was filed electronically on August 27,
1998.
Please call the undersigned or Claudia Murphy at (617) 954-5192 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
