Exhibit 99.1

Contact: Leah Stearns

Vice President, Investor Relations & Treasurer

Telephone: (617) 375-7500

AMERICAN TOWER CORPORATION REPORTS

FIRST QUARTER 2014 FINANCIAL RESULTS

Boston, Massachusetts – May 1, 2014: American Tower Corporation (NYSE: AMT) today reported financial results for the quarter ended March 31, 2014.

Jim Taiclet, American Tower’s Chief Executive Officer stated, “The technology transition from 3G to 4G wireless services in the U.S. is in full swing. We expect 4G device penetration to expand from 26% to 33% during the course of 2014. This 3G to 4G transition, coupled with even more applications, games, music and video services is putting significant strain on wireless networks and is driving elevated demand for tower space.

We are experiencing the benefit of this phenomenon, not only on our legacy domestic sites, but also on the GTP assets we acquired last year, which are already exceeding our original expectations. The resulting strong growth in the U.S. business, augmented by our even faster growing international segment has put us firmly on track to achieve double-digit annual growth in AFFO per Share for the foreseeable future.”

FIRST QUARTER 2014 OPERATING RESULTS OVERVIEW

American Tower generated the following operating results for the quarter ended March 31, 2014 (unless otherwise indicated, all comparative information is presented against the quarter ended March 31, 2013).

Total revenue increased 22.6% to $984.1 million and total rental and management revenue increased 23.5% to $960.1 million. Total rental and management revenue Core Growth was approximately 30.2%, and total rental and management Organic Core Growth was approximately 11.5%. Please refer to the selected statement of operations detail on page 12, which highlights the items affecting all Core Growth percentages for the quarter ended March 31, 2014.

Total rental and management Gross Margin increased 20.7% to $712.3 million. Total selling, general, administrative and development expense was $110.0 million, including $24.1 million of stock-based compensation expense. Adjusted EBITDA increased 22.1% to $640.5 million, Core Growth in Adjusted EBITDA was 28.3%, and Adjusted EBITDA Margin was 65%.

Adjusted Funds From Operations (AFFO) increased 22.8% to $439.3 million, AFFO per Share increased 22.2% to $1.10, and Core Growth in AFFO was approximately 28.2%.

Operating income increased 18.0% to $353.6 million, and net income attributable to American Tower Corporation increased 18.1% to $202.5 million. Net income attributable to American Tower Corporation per both basic and diluted common share increased 18.6% to $0.51.

Cash provided by operating activities increased 20.9% to $476.6 million.

Segment Results

Domestic Rental and Management Segment – Domestic rental and management segment revenue increased 23.3% to $635.8 million, and Organic Core Growth in domestic rental and management segment revenue was 9.2%. Domestic rental and management segment Gross Margin increased 21.3% to $514.3 million. Domestic rental and management segment Operating Profit increased 21.4% to $486.9 million, which represented 73% of total Operating Profit. Domestic rental and management segment Operating Profit Margin was 77%.

International Rental and Management Segment – International rental and management segment revenue increased 23.9% to $324.3 million, and Organic Core Growth in international rental and management segment revenue was 16.1%. International rental and management segment Gross Margin increased 19.2% to $198.0 million, while international rental and management segment Operating Profit increased 23.6% to $168.8 million, which represented 25% of total Operating Profit. International rental and management segment Operating Profit Margin was 52% (70%, excluding the impact of $82.4 million of pass-through revenues).

Network Development Services Segment – Network development services segment revenue was $24.0 million. Network development services segment Gross Margin was $14.2 million, and network development services segment Operating Profit was $11.6 million, which represented 2% of total Operating Profit. Network development services segment Operating Profit Margin was 49%.

Please refer to “Non-GAAP and Defined Financial Measures” on pages 4 and 5 for definitions of Gross Margin, Operating Profit, Operating Profit Margin, Adjusted EBITDA, Adjusted EBITDA Margin, NAREIT Funds From Operations, AFFO, AFFO per Share, Core Growth, Organic Core Growth, New Property Core Growth and Net Leverage Ratio. For additional financial information, including reconciliations to GAAP measures, please refer to the unaudited selected financial information on pages 10 through 13.

INVESTING OVERVIEW

Distributions – On April 25, 2014, the Company paid its first quarter distribution of $0.32 per share, or a total of approximately $126.6 million, to stockholders of record at the close of business on April 10, 2014.

Cash Paid for Capital Expenditures – During the first quarter of 2014, total capital expenditures of $213.9 million included:

Cash Paid for Acquisitions – During the first quarter of 2014, the Company spent $62.8 million for acquisitions, which was primarily related to sites acquired during December 2013.

Subsequent to the end of the first quarter of 2014, the Company acquired entities holding a portfolio of 60 communications sites and related assets in the U.S., which are primarily leased to radio and television broadcast tenants, from Richland Properties LLC (“Richland”). Total consideration for the acquisition was approximately $385.9 million, which included the assumption of approximately $196.5 million of secured debt.

FINANCING OVERVIEW

Leverage – For the quarter ended March 31, 2014, the Company’s Net Leverage Ratio was approximately 5.5x net debt (total debt less cash and cash equivalents) to first quarter 2014 annualized Adjusted EBITDA.

Liquidity – As of March 31, 2014, the Company had approximately $3.2 billion of total liquidity, comprised of the ability to borrow up to an aggregate of approximately $2.8 billion under its three revolving credit facilities, net of any outstanding letters of credit, and over $0.3 billion in cash and cash equivalents.

FULL YEAR 2014 OUTLOOK

The following estimates are based on a number of assumptions that management believes to be reasonable and reflect the Company’s expectations as of May 1, 2014. Actual results may differ materially from these estimates as a result of various factors, and the Company refers you to the cautionary language regarding “forward-looking” statements included in this press release when considering this information.

The Company’s outlook is based on the following average foreign currency exchange rates to 1.00 U.S. Dollar for the remainder of 2014: (a) 2.35 Brazilian Reais; (b) 550.00 Chilean Pesos; (c) 2,000.00 Colombian Pesos; (d) 0.75 Euros; (e) 2.75 Ghanaian Cedi; (f) 61.00 Indian Rupees; (g) 13.10 Mexican Pesos; (h) 2.80 Peruvian Soles; (i) 10.80 South African Rand; and (j) 2,500.00 Ugandan Shillings.

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As reflected in the table below, the Company has raised the midpoint of its full year 2014 outlook for total rental and management revenue by $70 million, Adjusted EBITDA by $50 million and AFFO by $35 million. These estimates include the acquisition of Richland in the U.S.

The Company’s outlook for total rental and management revenue reflects the following at the midpoint:

The calculation of midpoint Core Growth is as follows:

(Totals may not add due to rounding.)

Total Rental and Management Revenue Core Growth Components⁽¹⁾:

(Totals may not add due to rounding.)

Outlook for Capital Expenditures:

($ in millions)

(Totals may not add due to rounding.)

Reconciliations of Outlook for Net Income to Adjusted EBITDA:

($ in millions)

(Totals may not add due to rounding.)

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Reconciliations of Outlook for Net Income to AFFO:

($ in millions)

(Totals may not add due to rounding.)

Conference Call Information

American Tower will host a conference call today at 8:30 a.m. ET to discuss its financial results for the three months ended March 31, 2014 and its outlook for 2014. Supplemental materials for the call will be available on the Company’s website, www.americantower.com. The conference call dial-in numbers are as follows:

U.S./Canada dial-in: (866) 740-9153

International dial-in: (706) 645-9644

Passcode: 30664545

When available, a replay of the call can be accessed until 11:59 p.m. ET on May 14, 2014. The replay dial-in numbers are as follows:

U.S./Canada dial-in: (855) 859-2056

International dial-in: (404) 537-3406

Passcode: 30664545

American Tower will also sponsor a live simulcast and replay of the call on its website, www.americantower.com.

About American Tower

American Tower is a leading independent owner, operator and developer of wireless and broadcast communications real estate. American Tower currently owns and operates approximately 68,000 communications sites in the United States, Brazil, Chile, Colombia, Costa Rica, Germany, Ghana, India, Mexico, Panama, Peru, South Africa and Uganda. For more information about American Tower, please visit the “Earnings Materials” and “Company & Industry Resources” sections of our investor relations website at www.americantower.com.

Non-GAAP and Defined Financial Measures

In addition to the results prepared in accordance with generally accepted accounting principles in the United States (GAAP) provided throughout this press release, the Company has presented the following non-GAAP and defined financial measures: Gross Margin, Operating Profit, Operating Profit Margin, Adjusted EBITDA, Adjusted EBITDA Margin, NAREIT Funds From Operations, AFFO, AFFO per Share, Core Growth, Organic Core Growth, New Property Core Growth and Net Leverage Ratio. The Company uses Funds From Operations as defined by the National Association of Real Estate Investment Trusts (NAREIT), referred to herein as NAREIT FFO.

The Company defines Gross Margin as revenues less operating expenses, excluding stock-based compensation expense recorded in costs of operations, depreciation, amortization and accretion, selling, general, administrative and development expense, and other operating expenses. The Company defines Operating Profit as Gross Margin less selling, general, administrative and development expense, excluding stock-based compensation expense and corporate expenses. For reporting purposes, the international rental and management segment Operating Profit and Gross Margin also include interest income, TV Azteca, net. These measures of Gross Margin and Operating Profit are also before interest income, interest expense, loss on retirement of long-term obligations, other (expense) income, net income (loss) attributable to non-controlling interest, income (loss) on equity method investments and income taxes. The Company defines Operating Profit Margin as the percentage that results from dividing Operating Profit by revenue. The Company defines Adjusted EBITDA as net income before income (loss) from discontinued operations, net, income (loss) from equity method investments, income tax provision (benefit), other income (expense), loss on retirement of long-term obligations, interest expense, interest income, other operating income (expense), depreciation, amortization and accretion and stock-based compensation expense. The Company defines Adjusted EBITDA Margin as the percentage that results from dividing Adjusted EBITDA by total revenue. NAREIT FFO is defined as net income before gains or losses from the sale or disposal of real estate, real estate related impairment charges and real estate related depreciation, amortization and accretion, and including adjustments for (i) unconsolidated affiliates and (ii) noncontrolling interest. The Company defines AFFO as NAREIT FFO before (i) straight-line revenue and expense, (ii) stock-based compensation expense, (iii) the non-cash portion of our tax provision, (iv) non-real estate related depreciation, amortization and accretion, (v) amortization of deferred financing costs, capitalized interest, debt discounts and premiums and long-term deferred interest, (vi) other income (expense), (vii) loss on retirement of long-term obligations, (viii) other operating income (expense), and adjustments for (ix) unconsolidated affiliates, and (x) noncontrolling interest, less cash payments related to capital improvements and cash payments related to corporate capital expenditures. The

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Company defines AFFO per Share as AFFO divided by the diluted weighted average common shares outstanding. The Company defines Core Growth in total rental and management revenue, Adjusted EBITDA and AFFO as the increase or decrease, expressed as a percentage, resulting from a comparison of financial results for a current period with corresponding financial results for the corresponding period in a prior year, in each case, excluding the impact of straight-line revenue and expense recognition, foreign currency exchange rate fluctuations and significant one-time items. The Company defines Organic Core Growth in rental and management revenue as the increase or decrease, expressed as a percentage, resulting from a comparison of financial results for a current period with corresponding financial results for the corresponding period in a prior year, in each case, excluding the impact of straight-line revenue and expense recognition, foreign currency exchange rate fluctuations, significant one-time items and revenue associated with new properties that the Company has added to the portfolio since the beginning of the prior period. The Company defines New Property Core Growth in rental and management revenue as the increase or decrease, expressed as a percentage, on the properties the Company has added to its portfolio since the beginning of the prior period, in each case, excluding the impact of straight-line revenue and expense recognition, foreign currency exchange rate fluctuations and significant one-time items. The Company defines Net Leverage Ratio as net debt (total debt, less cash and cash equivalents) divided by last quarter annualized Adjusted EBITDA. These measures are not intended to replace financial performance measures determined in accordance with GAAP. Rather, they are presented as additional information because management believes they are useful indicators of the current financial performance of the Company’s core businesses. The Company believes that these measures can assist in comparing company performances on a consistent basis irrespective of depreciation and amortization or capital structure. Depreciation and amortization can vary significantly among companies depending on accounting methods, particularly where acquisitions or non-operating factors, including historical cost bases, are involved. Notwithstanding the foregoing, the Company’s measures of Gross Margin, Operating Profit, Operating Profit Margin, Adjusted EBITDA, Adjusted EBITDA Margin, NAREIT FFO, AFFO, AFFO per Share, Core Growth, Organic Core Growth, New Property Core Growth and Net Leverage Ratio may not be comparable to similarly titled measures used by other companies.

Cautionary Language Regarding Forward-Looking Statements

This press release contains “forward-looking statements” concerning our goals, beliefs, expectations, strategies, objectives, plans, future operating results and underlying assumptions, and other statements that are not necessarily based on historical facts. Examples of these statements include, but are not limited to statements regarding our full year 2014 outlook, foreign currency exchange rates and our expectation regarding future growth of our AFFO per Share. Actual results may differ materially from those indicated in our forward-looking statements as a result of various important factors, including: (1) decrease in demand for our communications sites would materially and adversely affect our operating results, and we cannot control that demand; (2) if our tenants share site infrastructure to a significant degree or consolidate or merge, our growth, revenue and ability to generate positive cash flows could be materially and adversely affected; (3) our business is subject to government regulations and changes in current or future laws or regulations could restrict our ability to operate our business as we currently do; (4) our leverage and debt service obligations may materially and adversely affect us; (5) increasing competition in the tower industry may materially and adversely affect us; (6) our expansion initiatives involve a number of risks and uncertainties that could adversely affect our operating results, disrupt our operations or expose us to additional risk if we are not able to successfully integrate operations, assets and personnel; (7) our foreign operations are subject to economic, political and other risks that could materially and adversely affect our revenues or financial position, including risks associated with fluctuations in foreign currency exchange rates; (8) a substantial portion of our revenue is derived from a small number of tenants, and we are sensitive to changes in the creditworthiness and financial strength of our tenants; (9) we may fail to realize the growth prospects and cost savings anticipated as a result of our acquisition of MIP Tower Holdings LLC, the parent company of Global Tower Partners (GTP); (10) new technologies or changes in a tenant’s business model could make our tower leasing business less desirable and result in decreasing revenues; (11) if we fail to remain qualified as a REIT, we will be subject to tax at corporate income tax rates, which may substantially reduce funds otherwise available; (12) we may be limited in our ability to fund required distributions using cash generated through our TRSs; (13) complying with REIT requirements may limit our flexibility or cause us to forego otherwise attractive opportunities; (14) certain of our business activities may be subject to corporate level income tax and foreign taxes, which reduce our cash flows, and may create deferred and contingent tax liabilities; (15) we may need additional financing to fund capital expenditures, future growth and expansion initiatives and to satisfy our REIT distribution requirements; (16) if we are unable to protect our rights to the land under our towers, it could adversely affect our business and operating results; (17) if we are unable or choose not to exercise our rights to purchase towers that are subject to lease and sublease agreements at the end of the applicable period, our cash flows derived from such towers will be eliminated; (18) restrictive covenants in the agreements related to our securitization transactions, our credit facilities and our debt securities could materially and adversely affect our business by limiting flexibility; (19) we may incur goodwill and other intangible asset impairment charges, which could result in a significant reduction to our earnings; (20) our costs could increase and our revenues could decrease due to perceived health risks from radio emissions, especially if these perceived risks are substantiated; (21) we could have liability under environmental and occupational safety and health laws; and (22) our towers or data centers may be affected by natural disasters and other unforeseen events for which our insurance may not provide adequate coverage. For additional information regarding factors that may cause actual results to differ materially from those indicated in our forward-looking statements, we refer you to the information contained in Item 1A of our Form 10-K for the year ended December 31, 2013. We undertake no obligation to update the information contained in this press release to reflect subsequently occurring events or circumstances.

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UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS

(In thousands)

6

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(In thousands, except per share data)

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UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(In thousands)

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UNAUDITED RESULTS FROM OPERATIONS, BY SEGMENT

(In thousands, except percentages)

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UNAUDITED SELECTED FINANCIAL INFORMATION

(In thousands, except where noted. Totals may not add due to rounding.)

SELECTED BALANCE SHEET DETAIL:

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UNAUDITED SELECTED FINANCIAL INFORMATION

(In thousands, except where noted. Totals may not add due to rounding.)

SELECTED BALANCE SHEET DETAIL (CONTINUED):

SELECTED STATEMENT OF OPERATIONS DETAIL:

Total rental and management straight-line revenue and expense (1):

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UNAUDITED SELECTED FINANCIAL INFORMATION

($ in thousands. Totals may not add due to rounding.)

SELECTED STATEMENT OF OPERATIONS DETAIL (CONTINUED):

The following table reflects the estimated impact of foreign currency exchange rate fluctuations, straight-line revenue and expense recognition and material one-time items on total rental and management revenue, Adjusted EBITDA and AFFO:

The calculation of Core Growth is as follows:

The components of Core Growth in rental and management revenue are as follows:

SELECTED CASH FLOW DETAIL:

SELECTED PORTFOLIO DETAIL – OWNED SITES:

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UNAUDITED RECONCILIATIONS TO GAAP MEASURES AND THE CALCULATION OF DEFINED FINANCIAL MEASURES

(In thousands, except per share data and percentages. Totals may not add due to rounding.)

The reconciliation of net income to Adjusted EBITDA and the calculation of Adjusted EBITDA Margin are as follows:

The reconciliation of net income to NAREIT FFO and the calculation of AFFO and AFFO per Share are presented below:

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