As filed with the Securities and Exchange Commission on December 20, 2012

Registration No. 2-10816

811-00058

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933	x
Pre-Effective Amendment No.	¨
Post-Effective Amendment No. 105	x

and/or

REGISTRATION STATEMENT

UNDER

THE INVESTMENT COMPANY ACT OF 1940	x
Amendment No. 39	x
(Check appropriate box or boxes)

THE GEORGE PUTNAM FUND OF BOSTON

(Exact Name of Registrant as Specified in Charter)

One Post Office Square,

Boston, Massachusetts 02109

(Address of Principal Executive Offices) (Zip Code)

(617) 292-1000

Registrant’s Telephone Number, including Area Code

Copy to:

ROBERT T. BURNS, Vice President THE GEORGE PUTNAM FUND OF BOSTON One Post Office Square Boston, Massachusetts 02109 (Name and address of agent for service) JOHN W. GERSTMAYR, Esquire ROPES & GRAY LLP Prudential Tower 800 Boylston Street Boston, Massachusetts 02199-3600

It is proposed that this filing will become effective (check appropriate box)

¨ immediately upon filing pursuant to paragraph (b)

x on November 30, 2012 pursuant to paragraph (b)

¨ 60 days after filing pursuant to paragraph (a)(1)

¨ on (date) pursuant to paragraph (a)(1)

¨ 75 days after filing pursuant to paragraph (a)(2)

¨ on (date) pursuant to paragraph (a)(2) of Rule 485.

If appropriate, check the following box:

¨ this post-effective amendment designates a new effective date for a previously filed post-effective amendment.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 and the Investment Company Act of 1940, the Registrant certifies that it meets all of the requirements for effectiveness of this Registration Statement under Rule 485(b) under the Securities Act of 1933 and has duly caused this Amendment to its Registration Statement to be signed on its behalf by the undersigned, duly authorized, in the City of Boston, and The Commonwealth of Massachusetts, on the 20th day of December, 2012.

The George Putnam Fund of Boston
By:	/s/ Jonathan S. Horwitz, Executive Vice President, Principal Executive Officer and Compliance Liaison

Pursuant to the requirements of the Securities Act of 1933, this Amendment to the Registration Statement has been signed below by the following persons in the capacities and on the dates indicated:

Signature	Title
Jameson A. Baxter*	Chair, Board of Trustees
Robert L. Reynolds*	President and Trustee
Jonathan S. Horwitz*	Executive Vice President, Principal Executive Officer and Compliance Liaison
Steven D. Krichmar*	Vice President and Principal Financial Officer
Janet C. Smith*	Vice President, Principal Accounting Officer and Assistant Treasurer
Liaquat Ahamed*	Trustee
Ravi Akhoury*	Trustee

Barbara M. Baumann*	Trustee
Charles B. Curtis*	Trustee
Robert J. Darretta*	Trustee
Katinka Domotorffy*	Trustee
John A. Hill*	Trustee
Paul L. Joskow*	Trustee
Elizabeth T. Kennan*	Trustee
Kenneth R. Leibler*	Trustee
Robert E. Patterson*	Trustee
George Putnam, III*	Trustee
W. Thomas Stephens*	Trustee

By:	/s/ Jonathan S. Horwitz, as Attorney-in-Fact
December 20, 2012
*  Signed pursuant to power of attorney filed in Post- Effective Amendment No.104 to the Registrant’s Registration Statement on November 28, 2012

EXHIBIT INDEX

XBRL Instance Document	Ex-101.ins
XBRL Taxonomy Extension Schema Document	Ex-101.sch
XBRL Taxonomy Extension Calculation Linkbase Document	Ex-101.cal
XBRL Taxonomy Extension Labels Linkbase	Ex-101.lab
XBRL Taxonomy Extension Presentation Linkbase Document	Ex-101.pre
XBRL Taxonomy Extension Definition Linkbase	Ex-101.def