Exhibit 99.3

Unaudited Preliminary Pro Forma Condensed

Combined Financial Information

On July 18, 2017, Crown Castle International Corp. (“Crown Castle”, “Company” or “CCIC”) entered into a definitive agreement to acquire LTS Group Holdings LLC (“Lightower”) for approximately $7.1 billion in cash, subject to certain limited post-closing adjustments (“Lightower Acquisition”). Lightower owns or has rights to approximately 32,000 route miles of fiber located primarily in top metro markets in the Northeast, including Boston, New York and Philadelphia. On November 1, 2017, the Company closed the Lightower Acquisition, which was financed using (1) cash on hand, including proceeds from the July 2017 Equity Financings and August 2017 Senior Notes Offering, and (2) borrowings under the 2016 Revolver (each as defined below).

The accompanying unaudited preliminary pro forma condensed combined financial statements present the preliminary pro

forma combined financial position and results of operations of the combined company based upon the historical financial statements of Crown Castle and Lightower, after giving effect to the Lightower Acquisition.

The adjustments set forth herein and described in the accompanying footnotes are intended to reflect the impact of the Lightower Acquisition on Crown Castle. The accompanying unaudited preliminary pro forma condensed combined financial statements are based upon the historical financial statements and have been derived from the (1) audited consolidated financial statements of Crown Castle contained in its Annual Report on Form 10-K for the fiscal year ended December 31, 2016 and the unaudited condensed consolidated financial statements of Crown Castle contained in its Quarterly Report on Form 10-Q for the nine months ended September 30, 2017, and (2) consolidated statement of operations of LTS Group Holdings LLC for the year ended December 31, 2016 and the nine months ended September 30, 2017. References to “LTS Group Holdings LLC” refer to the collective operations of the Lightower assets.

The accompanying unaudited preliminary pro forma condensed combined financial statements are prepared using the purchase method of accounting, with Crown Castle treated as the acquirer and as if the Lightower Acquisition had been consummated on (1) September 30, 2017 for purposes of preparing the unaudited pro forma condensed combined balance sheet and (2) on January 1, 2016 for purposes of preparing the unaudited pro forma condensed combined statement of operations for the year ended December 31, 2016 and the nine months ended September 30, 2017. Crown Castle is in the process of obtaining a third-party valuation related to assets acquired and liabilities assumed from Lightower. Given the size and timing of the Lightower Acquisition, the amount of certain assets presented are based on preliminary valuations and are subject to adjustment as additional information is obtained and the third-party valuation is finalized. The primary areas of the purchase price allocation that are not finalized relate to fair values of property and equipment, intangibles, goodwill, and deferred revenues. However, as indicated in note (B) to the unaudited preliminary pro forma condensed combined financial statements, Crown Castle made preliminary estimates of major categories of assets and liabilities in preparing the unaudited preliminary pro forma condensed combined financial statements. Any excess purchase price over the acquired net assets, as adjusted to reflect estimated fair values, has been recorded as goodwill.

Crown Castle operates as a real estate investment trust (“REIT”) for U.S. federal income tax purposes. As a REIT, Crown Castle is generally entitled to a deduction for dividends that it pays and therefore is not subject to U.S. federal corporate income tax on its net taxable income that is currently distributed to its stockholders. However, Crown Castle may be subject to certain federal, state, local and foreign taxes on its income or assets, including (1) alternative minimum taxes, (2) taxes on any undistributed income, (3) taxes related to its taxable REIT subsidiaries (“TRSs”), (4) franchise taxes, (5) property taxes and (6) transfer taxes.

Based on preliminary tax studies, Crown Castle anticipates that a substantial amount of the assets and related income from the Lightower Acquisition will be included in the REIT, with certain non-qualifying assets being included in TRSs. Accordingly, the accompanying unaudited preliminary pro forma condensed combined financial statements have been prepared under the assumption that approximately 85% of Lightower’s assets and related income will be included in the REIT. Crown Castle will continue to evaluate the level of assets and related income that will be included in the REIT.

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The accompanying unaudited preliminary pro forma condensed combined financial statements are provided for illustrative purposes only and do not purport to represent what the actual consolidated results of operations or the consolidated financial position of Crown Castle would have been had the Lightower Acquisition occurred on the dates assumed, nor are they necessarily indicative of future consolidated results of operations or consolidated financial position. The accompanying unaudited preliminary pro forma condensed combined financial statements address a hypothetical situation, and actual results may differ from these unaudited preliminary pro forma condensed combined financial statements once Crown Castle has completed the tax and valuation studies necessary to finalize the required purchase price allocations. There can be no assurance that such finalization will not result in material changes. The unaudited preliminary pro forma condensed combined financial statements do not include the realization of potential cost savings from operating efficiencies or restructuring costs that may result from the Lightower Acquisition. The unaudited preliminary pro forma condensed combined financial statements should be read in conjunction with the separate historical consolidated financial statements and accompanying notes of Crown Castle, previously filed on Crown Castle’s Annual Report on Form 10-K for the fiscal year ended December 31, 2016 and Quarterly Report on Form 10-Q for the nine months ended September 30, 2017, and the separate historical consolidated financial statements and accompanying notes of LTS Group Holdings LLC for the year ended December 31, 2016 and nine months ended September 30, 2017 included elsewhere in this filing.

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Unaudited Preliminary Pro Forma Condensed Combined Balance Sheet

Crown Castle International Corp. and Subsidiaries

September 30, 2017

(In thousands of dollars, except share amounts)

See notes to unaudited preliminary pro forma condensed combined financial statements.

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Unaudited Preliminary Pro Forma Condensed Combined Statement of Operations

Crown Castle International Corp. and Subsidiaries

Year Ended December 31, 2016

(In thousands except per share data)

N/M:  Not meaningful

See notes to unaudited preliminary pro forma condensed combined financial statements.

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Unaudited Preliminary Pro Forma Condensed Combined Statement of Operations

Crown Castle International Corp. and Subsidiaries

Nine Months Ended September 30, 2017

(In thousands except per share data)

N/M: Not meaningful

See notes to unaudited preliminary pro forma condensed combined financial statements.

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Notes to Preliminary Pro Forma Condensed Combined Financial Information (Unaudited)

Crown Castle International Corp. and Subsidiaries

(tabular dollars in thousands)

The table below reflects the cash paid and financing sources for the Lightower Acquisition.

Additionally, dividends/distributions in excess of earnings were impacted by $50 million (reflected as a corresponding decrease in cash) for estimated transaction costs directly related to the Lightower Acquisition that we anticipate will be expensed. Such transaction costs have not been included in the unaudited preliminary pro forma condensed combined statement of operations.

No deferred taxes have been recorded for purposes of the unaudited preliminary pro forma condensed combined financial statements as Crown Castle expects that any provision for income taxes resulting from the Lightower Acquisition will be current tax. See notes D4 and F4. Crown Castle will continue to evaluate the level of assets and related income that will be included in the REIT.

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Notes to Preliminary Pro Forma Condensed Combined Financial Information (Unaudited)

Crown Castle International Corp. and Subsidiaries

(tabular dollars in thousands)

July 2017 Common Stock Offering

In July 2017, Crown Castle issued approximately 40.15 million shares of common stock resulting in net proceeds of approximately $3.8 billion (“July 2017 Common Stock Offering”). Crown Castle used the net proceeds from the July 2017 Common Stock Offering to partially fund the Lightower Acquisition and pay related fees and expenses. As of September 30, 2017, Crown Castle had approximately 406.3 million shares of common stock outstanding.

July 2017 Preferred Stock Offering

In July 2017, Crown Castle issued 1.65 million shares of the 6.875% Mandatory Convertible Preferred Stock and generated net proceeds of approximately $1.6 billion (“Mandatory Convertible Preferred Stock Offering” and, together with the July 2017 Common Stock Offering, “July 2017 Equity Financings”). Crown Castle used the net proceeds of the Mandatory Convertible Preferred Stock Offering to partially fund the Lightower Acquisition and pay related fees and expenses. Unless converted earlier, each outstanding share of the 6.875% Mandatory Convertible Preferred Stock will automatically convert into shares of Crown Castle common stock on August 1, 2020. Currently, each share of the 6.875% Mandatory Convertible Preferred Stock will convert into between 8.6806 shares (based on the current maximum conversion price of $115.20) and 10.4167 shares (based on the current minimum conversion price of $96.00) of common stock on August 1, 2020, depending on the applicable market value of the common stock and subject to certain anti-dilution adjustments. At any time prior to August 1, 2020, holders of the 6.875% Mandatory Convertible Preferred Stock may elect to convert all or a portion of their shares into common stock at the minimum conversion rate of 8.6806 shares of common stock per share of 6.875% Mandatory Convertible Preferred Stock, subject to certain anti-dilution adjustments. As of September 30, 2017, Crown Castle had approximately 1.65 million shares of the 6.875% Mandatory Convertible Preferred Stock outstanding.

August 2017 Senior Notes Offering

In August 2017, Crown Castle issued $750 million aggregate principal amount of 3.20% Senior Notes due September 2024 and $1.0 billion aggregate principal amount of 3.65% Senior Notes due September 2027 (collectively, “August 2017 Senior Notes Offering”). Crown Castle used the net proceeds of the August 2017 Senior Notes Offering to partially fund the Lightower Acquisition and pay related fees and expenses.

2016 Revolver proceeds

Additionally, in October 2017, Crown Castle drew $655 million under its $3.5 billion unsecured revolving credit facility (“2016 Revolver”). Crown Castle used a portion of the proceeds from the amount drawn from the 2016 Revolver to partially fund the Lightower Acquisition and pay related fees and expenses.

As of September 30, 2017, after giving effect to the October 2017 draw under the 2016 Revolver, Crown Castle had approximately $15.9 billion of debt and other obligations outstanding.

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Notes to Preliminary Pro Forma Condensed Combined Financial Information (Unaudited)

Crown Castle International Corp. and Subsidiaries

(tabular dollars in thousands)

Crown Castle will continue to evaluate the level of assets and related income that will be included in the REIT.

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Notes to Preliminary Pro Forma Condensed Combined Financial Information (Unaudited)

Crown Castle International Corp. and Subsidiaries

(tabular dollars in thousands)

The pro forma weighted-average common shares outstanding are inclusive of the impact of the 40.15 million shares of common stock issued in connection with the July 2017 Common Stock Offering, the proceeds of which were used to partially fund the Lightower Acquisition, as discussed previously in note B3.

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Notes to Preliminary Pro Forma Condensed Combined Financial Information (Unaudited)

Crown Castle International Corp. and Subsidiaries

(tabular dollars in thousands)

Crown Castle will continue to evaluate the level of assets and related income that will be included in the REIT.

The pro forma weighted-average common shares outstanding are inclusive of the impact of the 40.15 million shares of common stock issued in connection with the July 2017 Common Stock Offering, the proceeds of which were used to partially fund the Lightower Acquisition, as discussed previously in note B3.

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