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) October 6, 2015

SBA Communications Corporation

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (561) 995-7670

(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):

Purchase Agreement

On October 6, 2015, SBA Senior Finance, LLC (“SBA Senior Finance”), an indirect subsidiary of SBA Communications Corporation (the “Company”), entered into a Purchase Agreement (the “Purchase Agreement”) among SBA Senior Finance, Deutsche Bank Trust Company Americas, as trustee, and Barclays Capital Inc., Citigroup Global Markets Inc. and Deutsche Bank Securities Inc., as representatives of the several initial purchasers named on Schedule I thereto (the “Initial Purchasers”), pursuant to which SBA Tower Trust (the “Trust”), a New York common law trust established by an indirect subsidiary of the Company, agreed to sell $500 million principal amount of Secured Tower Revenue Securities, Series 2015-1C (the “2015-1C Tower Securities”) to the Initial Purchasers. The Purchase Agreement contained customary representations, warranties, conditions to closing, indemnification rights and obligations of the parties.

Upon issuance, the 2015-1C Tower Securities will have an anticipated repayment date of October 2020, a final maturity date of October 2045 and an interest rate of 3.156% per annum.

The Company expects the closing of the 2015-1C Tower Securities to occur on or about October 14, 2015. The Company intends to use the net proceeds from this offering to make a cash distribution to SBA Guarantor LLC which will further distribute such amount to one or more other SBA entities to be used (1) to repay drawn amounts on the revolving credit facility of SBA Senior Finance II LLC, and (2) for general corporate purposes.

The Company and certain of its affiliates have previously entered into commercial financial arrangements with each of the Initial Purchasers, and/or their respective affiliates, and each of these entities and/or its affiliates has in the past provided financial, advisory, investment banking and other services to the Company and its affiliates, including (1) serving as a lender and/or in other related capacities in connection with the Senior Credit Agreement and the various term loans and revolving credit facility under the Senior Credit Agreement and/or (2) as a book runner and/or an initial purchaser for our Secured Tower Revenue Securities, Series 2014-1, Series 2014-2, Series 2013-1, Series 2013-2, Series 2012-1 and Series 2010-2. In addition, each of Barclays Capital Inc., Citigroup Global Markets Inc., Deutsche Bank Securities Inc., J.P. Morgan Securities LLC, Wells Fargo Securities, LLC, and TD Securities (USA) LLC served as a book runner and/or an initial purchaser for our 4.875% Senior Notes due 2022, 5.75% Senior Notes due 2020 and 5.625% Senior Notes due 2019.

On October 6, 2015, the Company issued a press release announcing the pricing of its $500 million principal amount of 2015-1C Tower Securities. A copy of the press release is filed herewith as Exhibit 99.1.

(d) Exhibits

SIGNATURES

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.

Date: October 9, 2015