As filed with the U.S. Securities and Exchange Commission on October 23, 2014

                            File Nos. 333-179904 and 811-22649                                                                             

 UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933	x
Post-Effective Amendment No. 119	x
and/or
REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940	x
Amendment No. 119	x

(Check appropriate box or boxes)

iShares U.S. ETF Trust

(Exact Name of Registrant as Specified in Charter)

c/o State Street Bank and Trust Company

1 Iron Street

Boston, MA 02210

(Address of Principal Executive Office)(Zip Code)

Registrant’s Telephone Number, including Area Code: (415) 670-2000

The Corporation Trust Company

1209 Orange Street

Wilmington, DE 19801

(Name and Address of Agent for Service)

With Copies to:

MARGERY K. NEALE, ESQ.	BENJAMIN J. HASKIN, ESQ.	EDWARD BAER, ESQ.
WILLKIE FARR & GALLAGHER LLP	WILLKIE FARR & GALLAGHER LLP	BLACKROCK FUND ADVISORS
787 SEVENTH AVENUE	1875 K STREET, N.W.	400 HOWARD STREET
NEW YORK, NY 10019-6099	WASHINGTON, D.C. 20006-1238	SAN FRANCISCO, CA 94105

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

¨     Immediately upon filing pursuant to paragraph (b)	x    On November 21, 2014, 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)

If appropriate, check the following box:

x The post-effective amendment designates a new effective date for a previously filed post-effective amendment.

Explanatory Note

This Post-Effective Amendment No. 119 to the Registrant’s Registration Statement on Form N-1A is being filed pursuant to paragraph (b)(1)(iii) of Rule 485 of the Securities Act of 1933, as amended (the “1933 Act”), solely for the purpose of delaying, until November 21, 2014, the effectiveness of the registration statement for the iShares Interest Rate Hedged Emerging Markets Bond ETF (the “Fund”), filed in Post-Effective Amendment No. 37 on December 6, 2013, pursuant to paragraph (a) of Rule 485 of the 1933 Act.

The effectiveness of the Registration Statement of the Fund was previously delayed pursuant to paragraph (b)(1)(iii) of Rule 485 of the 1933 Act as follows:

PEA No.	Date Filed	Automatic Effective Date
60	February 18, 2014	March 21, 2014
72	March 20, 2014	April 18, 2014
77	April 17, 2014	May 16, 2014
83	May 15, 2014	June 13, 2014
88	June 12, 2014	July 11, 2014
94	July 10, 2014	August 1, 2014
99	July 31, 2014	August 29, 2014
106	August 28, 2014	September 26, 2014
113	September 25, 2014	October 24, 2014

This Post-Effective Amendment No. 119 incorporates by reference the information contained in Parts A, B and C of Post-Effective Amendment No. 37.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, and the Investment Company Act of 1940, as amended, the Registrant certifies that it meets all the requirements for the effectiveness of this Registration Statement pursuant to Rule 485(b)(1)(iii) of the Securities Act of 1933, as amended, and has duly caused this Post-Effective Amendment No. 119 to the Registration Statement to be signed on its behalf by the undersigned, duly authorized, in the City of San Francisco and the State of California on the 23rd day of October, 2014.

iSHARES U.S. ETF TRUST 

By:
	Manish Mehta*
	President
	Date: October 23, 2014

Pursuant to the requirements of the Securities Act of 1933, as amended, this Post-Effective Amendment No. 119 to the Registration Statement has been signed below by the following persons in the capacities and on the date indicated.

By:
	Mark Wiedman*
	Trustee
	Date: October 23, 2014
	John E. Martinez*
	Trustee
	Date: October 23, 2014
	George G.C. Parker*
	Trustee
	Date: October 23, 2014
	Cecilia H. Herbert*
	Trustee
	Date: October 23, 2014
	Charles A. Hurty*
	Trustee
	Date: October 23, 2014

	John E. Kerrigan*
	Trustee
	Date: October 23, 2014
	Robert H. Silver*
	Trustee
	Date: October 23, 2014
	Robert S. Kapito*
	Trustee
	Date: October 23, 2014
	Madhav V. Rajan*
	Trustee
	Date: October 23, 2014
	/s/ Jack Gee
	Jack Gee
	Treasurer
	Date: October 23, 2014
* By:	/s/ Jack Gee
	Jack Gee
	Attorney-in-fact
	Date: October 23, 2014

* Powers of Attorney, each dated December 31, 2013, for Manish Mehta, Mark Wiedman, Charles A. Hurty, Cecilia H. Herbert, John E. Kerrigan, Robert H. Silver, George G.C. Parker, John E. Martinez, Madhav V. Rajan and Robert S. Kapito are incorporated herein by reference to Post-Effective Amendment No. 46, filed January 10, 2014.