As filed with the United States Securities and Exchange Commission on January 4, 2013

1933 Act Registration. No. 002-58287
1940 Act Registration. No. 811-02729

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933	þ
Pre-Effective Amendment No.	o
Post-Effective Amendment No. 65	þ

and/or

REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940	þ
Amendment No. 66

(Check appropriate box or boxes.)

SHORT-TERM INVESTMENTS TRUST

(Exact Name of Registrant as Specified in Charter)

11 Greenway Plaza, Suite 1000, Houston, TX   77046-1173
(Address of Principal Executive Offices)   (Zip Code)

Registrant’s Telephone Number, including Area Code (713) 626-1919

John M. Zerr, Esquire
11 Greenway Plaza, Suite 1000, Houston, TX 77046-1173
(Name and Address of Agent for Service)

Copy to:

Seba Kurian, Esquire	E. Carolan Berkley, Esquire
Invesco Advisers, Inc.	Stradley Ronon, Stevens & Young, LLP
11 Greenway Plaza, Suite 1000	2600 One Commerce Square
Houston, Texas 77046-1173	Philadelphia, Pennsylvania 19103
Approximate Date of Proposed Public Offering: As soon as practicable after the effective date of this Amendment

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

þ immediately upon filing pursuant to paragraph (b)

o on [Date] pursuant to paragraph (b)

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

o on [Date] pursuant to paragraph (a)(1)

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

o on [Date] pursuant to paragraph (a)(2) of rule 485.

If appropriate, check the following box:

o 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 pursuant to 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, thereunto duly authorized, in the city of Houston, Texas on the 4^th day of January, 2013.

Registrant:	SHORT-TERM INVESTMENTS TRUST
	By:	/s/ Karen Dunn Kelley       Karen Dunn Kelley, President

     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:

SIGNATURES	TITLE	DATE
/s/ Karen Dunn Kelley (Karen Dunn Kelley)	President  (Principal Executive Officer)	January 4, 2013
/s/ David C. Arch* (David C. Arch)	Trustee	January 4, 2013
/s/ Frank S. Bayley* (Frank S. Bayley)	Trustee	January 4, 2013
/s/ James T. Bunch* (James T. Bunch)	Trustee	January 4, 2013
/s/ Bruce L. Crockett* (Bruce L. Crockett)	Chair & Trustee	January 4, 2013
/s/ Rodney Dammeyer* (Rodney Dammeyer)	Trustee	January 4, 2013
/s/ Albert R. Dowden* (Albert R. Dowden)	Trustee	January 4, 2013
/s/ Martin L. Flanagan* (Martin L. Flanagan)	Trustee	January 4, 2013
/s/ Jack M. Fields* (Jack M. Fields)	Trustee	January 4, 2013
/s/ Carl Frischling* (Carl Frischling)	Trustee	January 4, 2013
/s/ Prema Mathai-Davis* (Prema Mathai-Davis)	Trustee	January 4, 2013
/s/ Larry Soll* (Larry Soll)	Trustee	January 4, 2013

	SIGNATURES	TITLE	DATE
	/s/ Hugo F. Sonnenschein* (Hugo F. Sonnenschein)	Trustee	January 4, 2013
	/s/ Raymond Stickel, Jr.* (Raymond Stickel, Jr.)	Trustee	January 4, 2013
	/s/ Wayne W. Whalen* (Wayne W. Whalen)	Trustee	January 4, 2013
	/s/ Sheri Morris (Sheri Morris)	Vice President & Treasurer (Principal Financial and  Accounting Officer)	January 4, 2013
*By	/s/ Philip A. Taylor Philip A. Taylor Attorney-in-Fact

* Philip A. Taylor, pursuant to powers of attorney filed in Registrant’s Post-Effective Amendment No. 61 on December 21, 2010.

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