UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K/A

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 27, 2015

AMERICAN TOWER CORPORATION

(Exact Name of Registrant as Specified in Charter)

116 Huntington Avenue

Boston, Massachusetts  02116

(Address of Principal Executive Offices)  (Zip Code)

(617) 375-7500

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

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):

Item 2.01        Completion of Acquisition or Disposition of Assets.

As previously reported on its Current Report on Form 8-K filed with the Securities and Exchange Commission (the “SEC”) on March 30, 2015 (the “Closing 8-K”), American Tower Corporation (the “Company”), through certain of its wholly owned subsidiaries, completed its acquisition of the exclusive right to lease, acquire or otherwise operate and manage 11,448 wireless communications sites from certain subsidiaries of Verizon Communications Inc. (“Verizon”) for approximately $5.053 billion in cash (the “Verizon Transaction”) on March 27, 2015.

For a description of the Verizon Transaction and the related agreements, see Item 1.01 of the Company’s Current Report on Form 8-K filed with the SEC on February 5, 2015, as supplemented by the Closing 8-K.

This Current Report on Form 8-K/A amends the Closing 8-K and is being filed to provide the financial statements and pro forma financial information relating to the Verizon Transaction set forth below under Item 9.01. In entering into the Verizon Transaction, the Company evaluated, among other things, sources of revenue (including, but not limited to, the lease to Verizon, described more fully in the Closing 8-K) and expenses (including, but not limited to, expenses associated with leases, property taxes, repairs and maintenance and utilities, as well as other operating expenses and selling, general and administrative expenses). After reasonable inquiry, management is not aware of any other material factors affecting these sites that would cause the reported financial information not to be indicative of their future operating results, other than as disclosed in the pro forma financial information.

Item 9.01        Financial Statements and Exhibits.

(a) Financial statements of real estate operations acquired

(b) Pro forma financial information

The following unaudited pro forma condensed combined financial information of the Company, giving effect to the Verizon Transaction, is attached as Exhibit 99.2 hereto and is incorporated herein by reference:

(d) Exhibits

Exhibit No. Description

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.

EXHIBIT INDEX

Exhibit No. Description