Post-effective Amendment (investment Company, Rule 485(a)) (485apos)

As filed with the Securities and Exchange Commission on August 28, 2013

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1933 Act Registration No. 333-182308 1940 Act Registration No. 811-22717 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM N-1A REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 [ ] Pre-Effective Amendment No. __ [ ] Post-Effective Amendment No. 23 [X] and/or REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940 [ ] Amendment No. 25 [X]

FIRST TRUST EXCHANGE-TRADED FUND VI
(Exact name of registrant as specified in charter)

120 East Liberty Drive, Suite 400
Wheaton, Illinois 60187
(Address of Principal Executive Offices) (Zip Code)

REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: [phone]

W. Scott Jardine, Esq., Secretary
First Trust Exchange-Traded Fund VI
First Trust Advisors L.P.
120 East Liberty Drive, Suite 400
Wheaton, Illinois 60187
(Name and Address of Agent for Service)

Copy to:
Eric F. Fess, Esq.
Chapman and Cutler LLP
111 West Monroe Street
Chicago, Illinois 60603

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

[X] immediately upon filing pursuant to paragraph (b)
[ ] on ___________ 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.

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This Registration Statement relates to International Multi-Asset Diversified Income Index Fund, a series of the Registrant.

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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 Registration Statement to be signed on its behalf by the undersigned, duly authorized in the City of Wheaton, and State of Illinois, on the 28th day of August, 2013.

FIRST TRUST EXCHANGE-TRADED FUND VI

By: /s/ Mark R. Bradley ------------------------------------- Mark R. Bradley, President and Chief Executive Officer

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

SIGNATURE TITLE DATE President and Chief Executive August 28, 2013 /s/ Mark R. Bradley Officer ------------------------ Mark R. Bradley Treasurer, Chief Financial Officer August 28, 2013 /s/ James M. Dykas and Chief Accounting Officer ------------------------ James M. Dykas ) James A. Bowen* Trustee ) ) ) Richard E. Erickson* Trustee ) ) ) Thomas R. Kadlec* Trustee ) ) ) Robert F. Keith* Trustee ) BY: /s/ W. Scott Jardine ) ------------------------- ) W. Scott Jardine Niel B. Nielson * Trustee ) Attorney-In-Fact ) August 28, 2013

* Original powers of attorney authorizing James A. Bowen, W. Scott Jardine, Mark R. Bradley, Eric F. Fess and Kristi A. Maher to execute Registrant's Registration Statement, and Amendments thereto, for each of the trustees of the Registrant on whose behalf this Registration Statement is filed, were previously executed, filed as an exhibit and are incorporated by reference herein.

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INDEX TO EXHIBITS

(101) Risk/return summary in interactive data format