MFS SERIES TRUST X, 497J, 1998-12-01

MFS SERIES TRUST X
497J, 1998-12-01
Previous: GLAMIS GOLD LTD, 8-K, 1998-12-01
Next: MFS SERIES TRUST X, 497, 1998-12-01


<PAGE>

                               MFS SERIES TRUST X
               500 Boylston Street Boston Massachusetts 02116-3741
                                617 954 5000




                                        December 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
              811-4992)  on Behalf of MFS  Government  Mortgage  Fund,  MFS     
              Strategic Value Fund, MFS Small Cap Value Fund and MFS Emerging 
              Markets Debt 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. 24 (the  "Amendment") to the Trust's  Registration
Statement on Form N-1A. The Amendment was filed  electronically  on November 25,
1998.

         Please call the undersigned or Martha Donovan at (617) 954-842 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