Exhibit 99.1

FOR IMMEDIATE RELEASE

GLOBAL BRASS AND COPPER HOLDINGS, INC. REPORTS FIRST

QUARTER 2014 FINANCIAL RESULTS

First Quarter Highlights

Schaumburg, IL., May 7, 2014 Global Brass and Copper Holdings, Inc. (NYSE:BRSS) (“GBC” or the “Company”) today announced the results for the first quarter ended March 31, 2014.

First Quarter Operating Results

Volume for the first quarter of 2014 increased by 2.1% to 134.2 million pounds compared to 131.5 million pounds in the first quarter of 2013. The increase in volume was the result of higher demand in the building and housing, automotive, coinage and munitions end markets. These increases were partially offset by lower demand in the electronics/electrical components end market resulting from customers sourcing their finished products offshore, which resulted in reduced demand for brass rod in this end market. By segment, Olin Brass, Chase Brass, and A.J. Oster volume increased 1.7%, 1.6%, and 1.2% during the first quarter, respectively.

“Increasing volumes across the business coupled with ongoing momentum in Eco Brass, our lead-free product portfolio, drove first quarter performance,” said John Wasz, GBC’s President and Chief Executive Officer. “We continue to make disciplined investments to bolster our future growth, strengthen our industry leading product portfolio, optimize efficiencies in our supply chain and drive our continuous improvement initiatives. While we did experience some short-term weather-related disruptions and sub-par operational performance during the first quarter, we have great confidence in our business and the strategy we are executing to create shareholder value.”

Net sales for the first quarter of 2014 decreased by 0.3% to $443.8 million compared to $445.0 million in the first quarter of 2013. The decline in net sales was attributable to lower metal prices and a shift in product mix, partially offset by an increase in average selling prices, higher volume and as a result of higher sales of unprocessed metal. Adjusted sales, a non-GAAP financial measure which reflects the value added premium over metal replacement cost recovery, increased by 1.2% to $141.3 million for the first quarter of 2014 from $139.6 million for the same period of 2013. A reconciliation of net sales to adjusted sales is provided later in this press release.

Net income attributable to GBC for the quarter was $9.7 million, or $0.46 per diluted share, compared to net income of $11.4 million, or $0.54 per diluted share, for the same period of 2013. The decrease in net income attributable to GBC for the quarter was primarily the result of the decrease in gross profit, partially offset by a decrease in selling, general and administrative expenses and a decrease in the provision for income taxes.

Consolidated Adjusted EBITDA, a non-GAAP measure of consolidated GBC profitability, was $28.7 million for the first quarter of 2014, a decrease of 4.7% compared to the first quarter of 2013, driven by higher manufacturing conversion costs and a shift in product mix. Partially offsetting the decrease were higher volume, increases in average selling prices, lower shrinkage costs and a decrease in selling, general and administrative costs. A reconciliation of net income attributable to Global Brass and Copper Holdings, Inc. to Consolidated Adjusted EBITDA is provided later in this press release.

Cash Flow and Leverage

During the first quarter of 2014, the Company reported net cash used in operating activities of $5.0 million driven by increased investment in working capital.

The Company ended the quarter with cash of $16.9 million, borrowings of $23.0 million under its asset based revolving lending facility (“ABL Facility”), senior secured notes of $375.0 million, and with borrowing availability of $176.5 million under its ABL Facility.

2014 Guidance

The Company is lowering its full-year 2014 guidance. For the full-year 2014, GBC expects:

The reduction reflects a lowering of near term growth expectations in automotive, building and housing, and coinage end markets versus management’s prior estimates, and the need for an additional quarter to resolve various operating issues at Olin Brass. While the Company expects second quarter volume and Consolidated Adjusted EBITDA to improve compared to first quarter, the Company does not expect year over year Consolidated Adjusted EBITDA growth until the second half of the year.

Conference Call

The Company will host a teleconference and webcast at 8:30 a.m. (Central Time) on Thursday, May 8 to review the results. To listen to the live call, individuals can access the webcast at the investor relations portion of the Company’s website at http://ir.gbcholdings.com, or by dialing 866-318-8614, passcode # 90110782 approximately 10 minutes before the scheduled start time. For those who cannot listen to the live broadcast, replays will be available shortly after the call on the Global Brass and Copper website.

About Global Brass and Copper

Global Brass and Copper Holdings, Inc. through its wholly-owned principal operating subsidiary, Global Brass and Copper, Inc., is a leading, value-added converter, fabricator, distributor and processor of specialized copper and brass products in North America. We engage in metal melting and casting, rolling, drawing, extruding and stamping to fabricate finished and semi-finished alloy products from processed scrap, copper cathode and other refined metals. Our products include a wide range of sheet, strip, foil, rod, tube and fabricated metal component products that we sell under the Olin Brass, Chase Brass and A.J. Oster brand names. Our products are used in a variety of applications across diversified end markets, including the building and housing, munitions, automotive, transportation, coinage, electronics/electrical components, industrial machinery and equipment and general consumer end markets.

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Global Brass and Copper Holdings, Inc.

Consolidated Statements of Operations (Unaudited)

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Global Brass and Copper Holdings, Inc.

Consolidated Adjusted EBITDA Reconciliation

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Segment Results of Operations

Segment Adjusted EBITDA Reconciliation

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Global Brass and Copper Holdings, Inc.

Consolidated Balance Sheets (Unaudited)

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Global Brass and Copper Holdings, Inc.

Consolidated Statements of Cash Flows (Unaudited)

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Cautionary Statement Concerning Forward-Looking Statements

This press release contains “forward-looking statements” that involve risks and uncertainties. You can identify forward-looking statements because they contain words such as “believes”, “expects”, “projects”, “may”, “would”, “should”, “seeks”, “approximately”, “intends”, “plans”, “estimates”, “anticipates” or similar expressions that relate to our strategy, plans or intentions. All statements the Company makes relating to its estimated and projected earnings, margins, costs, expenditures, cash flows, growth rates and financial results or to its expectations regarding future industry trends are forward-looking statements. In addition, the Company, through its senior management, from time to time make forward-looking public statements concerning its expected future operations and performance and other developments. These forward-looking statements are subject to known and unknown risks, uncertainties and other factors that may change at any time, and, therefore, the Company’s actual results may differ materially from those that it expected. The Company derives many of its forward-looking statements from its operating budgets and forecasts, which are based upon many detailed assumptions. While the Company believes that its assumptions are reasonable, it is very difficult to predict the impact of known factors, and, of course, it is impossible to anticipate all factors that could affect the Company’s actual results. Actual results may differ materially from these expectations due to various risks and uncertainties, including: the failure to maintain the Company’s balanced book approach which could cause increased volatility in the Company’s profitability and operating results and may result in significant losses; the loss in order volumes from any of the Company’s largest customers, which may reduce the Company’s sales volumes, revenues and cash flows; the disruption to the Company’s business if its customers shift their manufacturing offshore; the occurrence of any prolonged disruptions at or failures of the Company’s manufacturing facilities and equipment which could have a material adverse effect on its business, financial condition, results of operations and cash flows; disruptions arising from inclement weather; and the failure to implement the Company’s business strategy, including its growth initiatives, could adversely affect its business, financial condition, results of operations or cash flows. More detailed information about these and other risks and uncertainties are contained in the Company’s filings with the Securities and Exchange Commission, including under “Risk Factors” and elsewhere in our Annual Report on Form 10-K filed with the Securities and Exchange Commission on March 19, 2014. All forward-looking information in this press release is expressly qualified in its entirety by these cautionary statements. All forward-looking statements contained in this press release are based upon information available to the Company on the date of this press release.

In addition, the matters referred to in the forward-looking statements contained in this press release may not in fact occur. Accordingly, investors should not place undue reliance on those statements. The Company undertakes no obligation to publicly update or revise any forward-looking statement as a result of new information, future events or otherwise, except as otherwise required by law.

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Non-GAAP Measures

In addition to the results reported in accordance with U.S. GAAP, we have provided information regarding “Consolidated EBITDA”, “Segment EBITDA”, “Consolidated Adjusted EBITDA”, “Segment Adjusted EBITDA”, “Adjusted Diluted Earnings per Common Share” , and “Adjusted Sales”, each of which is defined below.

EBITDA-Based Measures

We define Consolidated EBITDA as net income (loss) attributable to Global Brass and Copper Holdings, Inc., adjusted to exclude interest expense, provision for (benefit from) income taxes, depreciation expense and amortization expense. Segment EBITDA is defined by us as income (loss) before provision for (benefit from) income taxes and equity income, adjusted to exclude interest expense, depreciation expense and amortization expense, in each case, to the extent such items are attributable to such segment.

We use Consolidated EBITDA only to calculate Consolidated Adjusted EBITDA. Consolidated Adjusted EBITDA is Consolidated EBITDA, further adjusted to exclude unrealized gains and losses on derivative contracts in support of our balanced book approach, unrealized gains and losses associated with derivative contracts related to electricity and natural gas costs, non-cash losses due to lower of cost or market adjustments to inventory, LIFO-based gains and losses due to the depletion of a LIFO layer of metal inventory, non-cash compensation expense related to payments made to certain members of our management by Halkos, share-based compensation expense, loss on extinguishment of debt, non-cash income accretion related to the Dowa Joint Venture, management fees paid to KPS Management II, L.P. and KPS Management III, L.P. (“KPS”), restructuring and other business transformation charges, specified legal and professional expenses and certain other items.

We use Segment EBITDA only to calculate Segment Adjusted EBITDA. Segment Adjusted EBITDA is Segment EBITDA, further adjusted to include equity income, net of tax and to exclude net income attributable to noncontrolling interest, unrealized gains and losses on derivative contracts in support of our balanced book approach, unrealized gains and losses associated with derivative contracts related to electricity and natural gas costs, non-cash losses due to lower of cost or market adjustments to inventory, LIFO-based gains and losses due to the depletion of a LIFO layer of metal inventory, non-cash compensation expense related to payments made to certain members of our management by Halkos, share-based compensation expense, loss on extinguishment of debt, non-cash income accretion related to the Dowa Joint Venture and restructuring and other business transformation charges, in each case, to the extent such items are attributable to the relevant segment.

We present the above-described EBITDA-based measures because we consider them important supplemental measures and believe they are frequently used by securities analysts, investors and other interested parties in the evaluation of companies in our industry. Nevertheless, our EBITDA-based measures may not be comparable to similarly titled measures presented by other companies.

We present Consolidated Adjusted EBITDA as a supplemental measure of our performance because we believe it represents a meaningful presentation of the financial performance of our core operations, without the impact of the various items excluded, in order to provide period-to-period comparisons that are more consistent and more easily understood. In addition, Segment Adjusted EBITDA is the key metric used by our chief operating decision-maker to evaluate the business performance of our segments in comparison to budgets, forecasts and prior-year financial results, providing a measure that management believes reflects our core operating performance.

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Our EBITDA-based measures are not intended as alternatives to net income (loss) as indicators of our operating performance, as alternatives to any other measure of performance in conformity with GAAP or as alternatives to cash flow provided by operating activities as measures of liquidity. You should therefore not place undue reliance on our EBITDA-based measures or ratios calculated using those measures. Our GAAP-based measures can be found in our consolidated financial statements included elsewhere in this press release.

Adjusted Diluted Earnings per Common Share

Adjusted Diluted Earnings per Common Share is defined as Diluted Income (Loss) per Common Share adjusted to remove the after-tax impact of the addbacks to EBITDA in calculating Consolidated Adjusted EBITDA. We believe that Adjusted Diluted Earnings per Common Share supplements our GAAP results to provide a more complete understanding of the results of our business, and we believe it is useful to our investors and other parties for these same reasons. Adjusted Diluted Earnings per Common Share may not be comparable to similarly titled measures presented by other companies and is not a measure of operating performance or liquidity defined by GAAP.

Adjusted Sales

Adjusted sales is defined as net sales less the metal component of net sales. Net sales is the most directly comparable GAAP measure to adjusted sales. Adjusted sales represents the value-added premium we earn over our conversion and fabrication costs. Management uses adjusted sales on a consolidated basis to monitor the revenues that are generated from our value-added conversion and fabrication processes excluding the effects of fluctuations in metal costs. We believe that adjusted sales supplements our GAAP results to provide a more complete understanding of the results of our business, and we believe it is useful to our investors and other parties for these same reasons. Adjusted sales may not be comparable to similarly titled measures presented by other companies and is not a measure of operating performance or liquidity defined by GAAP.

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