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MASSACHUSETTS FINANCIAL SERVICES COMPANY
500 BOYLSTON ST7REET, BOSTON, MASSACHUSETTS 02116
(617) 954-5000
June 5, 2000
VIA EDGAR
Securities and Exchange Commission
Judiciary Plaza
450 Fifth Street, NW
Washington, DC 20549
Re: MFS(R)Series Trust III (the "Trust") (File Nos. 2-60491 and
811-2794) on Behalf of MFS(R)High Income Fund ("MFH"),
MFS(R)Municipal High Income Fund ("MMH") and MFS(R)High Yield
Opportunities Fund ("HYO")
Ladies and Gentlemen:
Pursuant to Rule 497(j) under the Securities Act of 1933, as amended,
please accept this letter on behalf of the Trust 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 for MFH, MMH and
HYO to the Trust's Registration Statement on Form N-1A. The Amendment was filed
electronically on May 30, 2000.
Please call the undersigned or Shauna Fahey at (617) 954-5192 or (800)
343-2829 with any questions you may have.
Very truly yours,
HEATHER R. GIROLAMO
Heather R. Girolamo
Associate Counsel
HRG/bjn
