Exhibit 99.3

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL DATA

On August 16, 2016, U.S. Silica Holdings, Inc., a Delaware corporation (“U.S. Silica” or the “Company”), completed the Merger of New Birmingham, Inc., a Nevada corporation (“NBI”), the holding company of New Birmingham Resources, LLC (“NBR”). The Merger was completed pursuant to the terms of the previously announced Agreement and Plan of Merger, by and among the Company, New Birmingham Merger Corp., a Nevada corporation and wholly owned subsidiary of the Company (“Merger Sub 1”), NBI Merger Subsidiary II, Inc., a Delaware corporation and wholly owned subsidiary of the Company (“Merger Sub 2”), NBI, and each of David Durrett and Erik Dall as representatives of the sellers and option holders (the “Merger Agreement”), pursuant to which the Company acquired all of the outstanding capital stock of NBI through the Merger of Merger Sub 1 with and into NBI, followed immediately by the Merger of NBI with and into Merger Sub 2 (collectively, the “Merger”).

The consideration paid by the Company to the stockholders of NBI at the closing of the Merger consisted of $106,509,000 of net cash, subject to customary post-closing adjustment and 2,630,513 shares of common stock of the Company. A portion of the cash consideration has been deposited into escrow to support the post-closing purchase price adjustments and the sellers’ indemnification obligations.

The unaudited pro forma condensed combined financial statements have been prepared using the acquisition method of accounting in accordance with Accounting Standards Codification (“ASC”) 805, “Business Combinations”, with the Company treated as the legal and accounting acquirer. The following tables set forth unaudited pro forma combined financial data as of June 30, 2016, for the six months ended June 30, 2016, and for the twelve months ended December 31, 2015. The unaudited pro forma condensed combined balance sheet as of June 30, 2016 gives effect to the Merger as if it had occurred on that date. The pro forma balance sheet data is derived from the unaudited historical financial statements of U.S. Silica and NBI as of June 30, 2016. The unaudited pro forma combined statement of operations for the year ended December 31, 2015, and for the six months ended June 30, 2016 have been prepared to illustrate the effects of the Merger, as if it had occurred on January 1, 2015. The pro forma operations data is derived from the audited financial statements of U.S. Silica for the year ended December 31, 2015, the unaudited financial statements of U.S. Silica for the six months ended June 30, 2016, the audited financial statements of NBI for the year ended December 31, 2015, and the unaudited financial statements of NBI for the six months ended June 30, 2016.

The historical financial statements have been adjusted in the unaudited pro forma condensed combined financial statements to give effect to events that are (i) directly attributable to the Merger, (ii) factually supportable, and (iii) with respect to the statements of operations, expected to have a continuing impact on the combined company. The unaudited pro forma combined statements of operations do not reflect any non-recurring charges directly related to the Merger that the combined company may have incurred upon completion of the Merger. Further, the tax rate used for these unaudited pro forma condensed combined financial statements is an estimated effective tax rate, which will likely vary from the actual effective rate in periods subsequent to the completion of the Merger.

The unaudited pro forma condensed combined financial statements have been prepared for informational purposes only and are not necessarily indicative of what the combined company’s condensed consolidated financial position or results of operations actually would have been had the Merger been consummated prior to June 30, 2016, nor are they necessarily indicative of our future results of operations. In addition, the unaudited pro forma combined financial statements do not purport to project the future financial position or operating results of the combined company. The fair value of NBI’s identifiable tangible and intangible assets acquired and liabilities assumed are based on preliminary estimates. As of the date of filing of the Current Report on Form 8-K/A to which the following unaudited pro forma combined financial statements are attached, the Company has not completed the detailed valuation work necessary to finalize the required estimated fair values of the NBI assets acquired and liabilities assumed and related allocation of purchase price. The purchase price allocation and related depreciation, depletion

and amortization included in the unaudited pro forma combined financial statements are preliminary and have been made solely for purposes of preparing these unaudited pro forma condensed combined financial statements. Management anticipates that the values assigned to the assets acquired and liabilities assumed will be finalized during the one-year measurement period following the date of completion of the Merger. Differences between these preliminary estimates and the final acquisition accounting may occur and these differences could have a material impact on the unaudited pro forma condensed combined financial statements and the combined company’s future results of operations and financial position. In addition, certain reclassifications have been made to NBI’s historical financial statements to conform to the presentation used in the Company’s historical financial statements. Such reclassifications had no effect on NBI’s previously reported financial position or results of operations.

The unaudited pro forma condensed combined financial statements do not include any adjustments for the anticipated benefits from cost savings or synergies of U.S. Silica and NBI operating as a combined company or for liabilities resulting from integration planning, as management is in the process of making these assessments. However, liabilities ultimately may be recorded for additional costs in subsequent periods related to both companies, including severance, relocation or retention costs related to employees of both companies, as well as other costs associated with integrating and/or restructuring the companies. The ultimate recognition of such costs and liabilities would affect amounts in the unaudited pro forma combined financial statements, and such costs and liabilities could be material.

The unaudited pro forma condensed combined financial statements should be read in conjunction with the:

UNAUDITED PRO FORMA CONDENSED COMBINED BALANCE SHEET AS OF JUNE 30, 2016

(dollars in thousands)

UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT OF OPERATIONS FOR THE SIX MONTHS ENDED JUNE 30, 2016

(dollars in thousands)

UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT OF OPERATIONS FOR THE YEAR ENDED DECEMBER 31, 2015

(dollars in thousands)

NOTES TO UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS

The unaudited pro forma condensed combined financial statements are prepared in accordance with Article 11 of SEC Regulation S-X. The historical financial information has been adjusted to give effect to the events that are (i) directly attributable to the Merger, (ii) factually supportable and (iii) with respect to the unaudited pro forma condensed combined statements of income, expected to have a continuing impact on the operating results of the combined company. The historical financial information of U.S. Silica and NBI is presented in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”).

The acquisition accounting adjustments relating to the Merger are preliminary and subject to change, as additional information becomes available and as additional analyses are performed. There can be no assurances that the final valuations will not result in material changes to this preliminary purchase price allocation. The unaudited pro forma condensed combined financial statements do not give effect to the potential impact of any anticipated benefits from cost savings or synergies that may result from the Merger or to any future integration costs. The unaudited pro forma condensed combined financial statements do not purport to project the future operating results or financial position of the combined company following the Merger.

Certain reclassifications have been made to NBI’s historical financial statements to conform to the presentation used in U.S. Silica’s historical consolidated financial statements, including depreciation, depletion and amortization, and gain or loss on sales of assets. Such reclassifications had no effect on NBI’s previously reported financial position or results of operations.

Pursuant to the Merger Agreement, U.S. Silica paid $106,509,000 (net of $9,095,000 cash acquired) cash consideration and $106,562,000 in stock consideration. The calculation of the purchase price is as follows:

The following table sets forth a preliminary allocation of the purchase price to NBI’s identifiable tangible and intangible assets acquired and liabilities assumed by the Company:

Property, plant and mine development

Property, plant and mine development has been adjusted to its estimated fair value as discussed further in Note 4 below. The related depreciation and depletion costs are reflected as a pro forma adjustment in the unaudited pro forma condensed combined statements of operations, as further described in Note 5(b).

Identifiable intangible assets

Preliminary identifiable intangible assets in the pro forma financial information consist of anticipated intangibles derived from customer relationships with an estimated useful life of 15 years. The amortization related to these identifiable intangible assets is reflected as a pro forma adjustment in the unaudited pro forma condensed combined statements of operations, as further described in Note 5(b). The table below indicates the estimated fair value of customer relationships and estimated useful life:

Goodwill represents the excess of the purchase price over the fair value of the underlying net assets acquired. Goodwill in this transaction is attributable to planned growth in regional sand markets and synergies expected to be achieved from the combined operations of U.S. Silica and NBI.

Both customer relationships and goodwill are not expected to be deductible for tax purposes.

Pro Forma Adjustments

Represents the impact from use of restricted cash paid concurrent with or immediately subsequent to the closing of the Merger.

The unaudited pro forma condensed consolidated statements of operations for the year ended December 31, 2015 and for the six months ended June 30, 2016 have not been adjusted for non-recurring transaction costs incurred after the date of these financial statements or any other items that are expected to have a one-time impact on the pro forma combined net income in the twelve months following the Merger.

Pro Forma Adjustments