Certification of No Change in Definitive Materials. (497j)

Name	Symbol	Market	Type
Mfs Mid Cap Value Fund Share Class - 529A (MM)	NASDAQ:EACVX	NASDAQ	Fund

Name

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Market

Type

Mfs Mid Cap Value Fund Share Class - 529A (MM)

NASDAQ:EACVX

NASDAQ

Fund

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Certification of No Change in Definitive Materials. (497j)

01/02/2013 1:17pm

Edgar (US Regulatory)

111 Huntington Ave., Boston, Massachusetts 02199-7610

Phone 617-954-5000

February 1, 2013

VIA EDGAR

United States Securities and Exchange Commission

100 F Street, N.E.

Washington, DC 20549

Re:

MFS ® Series Trust XI (the “Trust”) (File Nos. 33-68310 and 811-7992) on Behalf of MFS ® Mid Cap Value Fund and MFS ® Blended Research ® Core Equity Fund (the “Funds”)

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. 35 (the “Amendment”) to the Trust’s Registration Statement on Form N-1A. The Amendment was filed electronically on January 25, 2013.

Please call the undersigned at (617) 954-5843 or Jessica McCormick at (617) 954-6149 with any questions you may have.

Very truly yours,

BRIAN E. LANGENFELD

Brian E. Langenfeld

Vice President & Senior Counsel

BEL/bjn

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EACVX Mfs Mid Cap Value Fund Share Class - 529A (MM)