Fidelity (logo) Investments®| 245 Summer Street
Boston MA 02210
617 563 7000

||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| August 16, 2013

U.S. Securities & Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Re:	Fidelity Commonwealth Trust (the trust):
	Fidelity Series 100 Index Fund (the fund)
	File Nos. 002-52322 and 811-02546

__________________________________________________________________________

Ladies and Gentlemen:

Transmitted herewith for filing pursuant to Rule 497(e) under the Securities Act of 1933 (33 Act), as amended, are exhibits containing interactive data format risk/return summary information for supplements to the registration statement for the fund listed above. The purpose of this filing is to submit the 497 filing in XBRL for the fund.

||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||	Very truly yours,
	/s/ Jeffrey LaFountain
	Jeffrey LaFountain
	Legal Product Group