UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): March 5, 2014

The ADT Corporation

(Exact Name of Registrant as Specified in Charter)

1501 Yamato Road

Boca Raton, Florida 33431

(Address of Principal Executive Offices, including Zip Code)

(561) 988-3600

(Registrant’s telephone number, including Area Code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

On March 5, 2014, The ADT Corporation (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) with Merrill Lynch, Pierce Fenner & Smith Incorporated, as representative for the several underwriters named therein (collectively, the “Underwriters”) providing for the offer and sale of $500,000,000 principal amount of the Company’s 4.125% Senior Notes due 2019 (the “Notes”).

The Company has made certain customary representations, warranties and covenants in the Underwriting Agreement concerning the Company and the Registration Statement related to the offering of the Notes, respectively. The Company also has agreed to indemnify the Underwriters against certain liabilities, including liabilities under the Securities Act of 1933, as amended.

The Notes offering is expected to close, subject to customary closing conditions, on March 19, 2014.

The foregoing description of the Underwriting Agreement is qualified in its entirety by reference to the Underwriting Agreement, a copy of which is filed as Exhibit 1.1 to this Form 8-K and incorporated by reference herein.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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