UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-K/A

Amendment No. 1

For the fiscal year ended July 31, 2012

OR

For the transition period from                    to                    

Commission file number 1-14959

BRADY CORPORATION

(Exact name of registrant as specified in charter)

6555 West Good Hope Road,

Milwaukee, WI 53223

(Address of principal executive offices) (Zip Code)

(414) 358-6600

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  x    No  ¨

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes  ¨    No  x

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  x    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of the registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definition of “large accelerated filer”, “accelerated filer”, and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    Yes  ¨    No  x

The aggregate market value of the non-voting common stock held by non-affiliates of the registrant as of January 31, 2012, was approximately $1,441,914,982 based on closing sale price of $32.37 per share on that date as reported for the New York Stock Exchange. As of September 20, 2012, there were 47,406,559 outstanding shares of Class A Nonvoting Common Stock (the “Class A Common Stock”), and 3,538,628 shares of Class B Common Stock. The Class B Common Stock, all of which is held by affiliates of the registrant, is the only voting stock.

Explanatory Note

We are filing this Amendment No. 1 on Form 10-K/A (this “Amendment”) to our Annual Report on Form 10-K for the fiscal year ended July 31, 2012, which was filed on September 27, 2012 (the “Original Form 10-K”), to amend and restate Exhibit 23 to correct a clerical error. This Amendment does not amend any other information set forth in the Original Form 10-K, and we have not updated the disclosures therein to reflect any events that may have occurred at a date subsequent to the date of the Original Form 10-K.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized this 28th day of September 2012.

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