Exhibit 99.1

Steel Dynamics Reports Second Quarter 2017 Results

FORT WAYNE, INDIANA, July 19, 2017 / PRNewswire / Steel Dynamics, Inc. (NASDAQ/GS: STLD) today announced second quarter 2017 financial results.  The company reported second quarter 2017 net income of $154 million, or $0.63 per diluted share, with net sales of $2.4 billion.  Comparatively, prior year second quarter net income was $142 million, or $0.58 per diluted share, with net sales of $2.0 billion.  Sequential first quarter 2017 net income was $201 million, or $0.82 per diluted share, with net sales of $2.4 billion.

“The team delivered a solid performance for the second quarter 2017 despite hesitant customer order entry and significantly higher quarter-over-quarter steel imports,” said Mark D. Millett, President and Chief Executive Officer. “Our second quarter 2017 income from operations was $265 million with a trailing twelve month adjusted EBITDA record of $1.4 billion.   The decrease in sequential quarterly earnings was principally driven by our flat roll operations, as increased average scrap costs outpaced average sales price growth.  As mentioned in our mid-quarter guidance, we had a planned galvanizing line upgrade at our Butler Flat Roll Division and also experienced some start-up issues at our new Columbus Flat Roll Division paint line, which increased expenses and decreased value-added flat roll shipments in the quarter.

“We believe the customer order hesitancy was related to anticipated scrap price changes rather than any underlying softness in demand.  Additionally, customer inventory levels continued to be positioned at historically low levels.  Steel demand from the automotive sector remained steady, as the construction and energy sectors continued to improve,” continued Millett.

“Second quarter 2017 operating income from our metals recycling platform remained aligned with the strong first quarter performance, in spite of somewhat lower shipments and metal spread, as the team continued to optimize costs throughout the business,” continued Millett. “The fabrication group achieved another quarter of record shipments, a solid indicator that the non-residential construction market is continuing a positive growth profile.”

Additional Second Quarter 2017 Comments

Second quarter 2017 operating income for the company’s steel operations decreased 22 percent, or $79 million, to $274 million sequentially, primarily related to two operational items within the flat roll operations and overall metal spread compression.  During the second quarter 2017, the company further modernized one of its galvanizing lines located at its Butler Flat Roll Division, while also expanding the line’s annual value-added production capability by an additional 180,000 tons.  The upgrade required the line to be down for three weeks in May.  Additionally, the company experienced quality issues related to the start-up of its new Galvalume and paint line at its Columbus Flat Roll Division, resulting in line downtime.  Combined, these two items resulted in higher costs and lower value-added shipments, reducing potential second quarter 2017 pretax earnings by an estimated $30 million.

The company’s average steel product price increased less than consumed raw material scrap costs, resulting in steel metal spread compression.  The second quarter 2017 average product selling price for the company’s steel operations increased $36 to $779 per ton.  The average ferrous scrap cost per ton melted increased $39 to $303 per ton.

Second quarter 2017 operating income attributable to the company’s flat roll products decreased 22 percent when compared to the sequential first quarter.  Operating income from long products decreased 24 percent as a result of an eight percent decrease in shipments, most significantly from the company’s Structural and Rail Division, despite record quarterly rail shipments.  Structural and merchant steel volumes remain under pressure from excess domestic production capability, coupled with elevated import levels.  The company’s steel production utilization rate was 91 percent in the second quarter 2017, compared to 95 percent in the sequential first quarter and compared to the estimated second quarter domestic industry utilization rate of 74 percent.

Second quarter 2017 operating income from the company’s metals recycling operations was $20 million, compared to $21 million in the sequential first quarter.  Higher average sales prices were offset by lower shipments, related in part to the company’s sale of certain southeastern U.S. locations at the end of the first quarter 2017.

The company’s fabrication operations recorded second quarter 2017 operating income of $20 million, compared to sequential first quarter results of $24 million.  The platform achieved a second consecutive quarter of record shipments.  However, metal spread compression based on higher average steel input costs more than offset the improved volume.

Year-to-Date June 30, 2017 Comparison

For the six months ended June 30, 2017, net income was $355 million, or $1.46 per diluted share, on net sales of $4.8 billion, as compared to net income of $205 million, or $0.84 per diluted share, on net sales of $3.8 billion for the same period in 2016.  First half 2017 net sales increased 26 percent.  Although all platforms experienced improved revenues, the improvement was driven by higher average steel product pricing.  First half 2017 operating income increased $212 million, or 55 percent, to $600 million, based on improved earnings from the company’s steel operations. The average year-to-date selling price for the company’s steel operations increased $153 to $761 per ton.  The average year-to-date ferrous scrap cost per ton melted increased $77 to $283 per ton.

During the first half of 2017, the company generated strong cash flow from operations of $321 million and maintained liquidity of $2.1 billion at June 30, 2017.  The company also repurchased $138 million of its common stock during the first half of 2017.

Outlook

“We remain optimistic that macroeconomic and market conditions are in place to benefit domestic steel consumption in the coming years,” said Millett.  “Although U.S. automotive production has peaked, we believe North American automotive steel consumption will be steady, and that there will be additional growth in the energy and construction sectors, especially for larger, public sector infrastructure projects.

“We continue to strengthen our financial position through strong cash flow generation and the execution of our long-term strategy. We are well-positioned for growth, and remain focused on delivering shareholder value through organic and strategic growth opportunities,” concluded Millett.

Conference Call and Webcast

Steel Dynamics, Inc. will hold a conference call to discuss second quarter 2017 operating and financial results on Thursday, July 20, 2017, at 10:00 a.m. Eastern Time.  You may access the call and find dial-in information on the Investors section of the company’s website at www.steeldynamics.com.  A replay of the call will be available on our website until 11:59 p.m. Eastern Time on July 25, 2017.

About Steel Dynamics, Inc.

Steel Dynamics, Inc. is one of the largest domestic steel producers and metals recyclers in the United States based on estimated annual steelmaking and metals recycling capability, with facilities located throughout the United States, and in Mexico.  Steel Dynamics produces steel products, including hot roll, cold roll, and coated sheet steel, structural steel beams and shapes, rail, engineered special-bar-quality steel, cold finished steel, merchant bar products, specialty steel sections and steel joists and deck.  In addition, the company produces liquid pig iron and processes and sells ferrous and nonferrous scrap.

Note Regarding Non-GAAP Financial Measures

The company reports its financial results in accordance with U.S. generally accepted accounting principles (GAAP). Management believes that Adjusted Operating Income, Adjusted Net Income, Adjusted Diluted Earnings Per Share, EBITDA and Adjusted EBITDA, non-GAAP financial measures, provide additional meaningful information regarding the company’s performance and financial strength. Non-GAAP financial measures should be viewed in addition to, and not as an alternative for, the company’s reported results prepared in accordance with GAAP.  In addition, because not all companies use identical calculations, EBITDA included in this release may not be comparable to similarly titled measures of other companies.

Forward-Looking Statements

This press release contains some predictive statements about future events, including statements related to conditions in the steel and metallic scrap markets, Steel Dynamics’ revenues, costs of purchased materials, future profitability and earnings, and the operation of new or existing facilities. These statements, which we generally precede or accompany by such typical conditional words as “anticipate,” “intend,” “believe,” “estimate,” “plan,” “seek,” “project” or “expect,” or by the words “may,” “will,” or “should,” are intended to be made as “forward-looking,” subject to many risks and uncertainties, within the safe harbor protections of the Private Securities Litigation Reform Act of 1995. These statements speak only as of this date and are based upon information and assumptions, which we consider reasonable as of this date, concerning our businesses and the environments in which they operate. Such predictive statements are not guarantees of future performance, and we undertake no duty to update or revise any such statements. Some factors that could cause such forward-looking statements to turn out differently than anticipated include: (1) the effects of uncertain economic conditions; (2) cyclical and changing industrial demand; (3) changes in conditions in any of the steel or scrap-consuming sectors of the economy which affect demand for our products, including the strength of the non-residential and residential construction, automotive, appliance, pipe and tube, and other steel-consuming industries; (4) fluctuations in the cost of key raw materials (including steel scrap, iron units, and energy costs) and our ability to pass-on any cost increases; (5) the impact of domestic and foreign import price competition; (6) unanticipated difficulties in integrating or starting up new or acquired businesses; (7) risks and uncertainties involving product and/or technology development; and (8) occurrences of unexpected plant outages or equipment failures.

More specifically, we refer you to Steel Dynamics’ more detailed explanation of these and other factors and risks that may cause such predictive statements to turn out differently, as set forth in our most recent Annual Report on Form 10-K under the headings Special Note Regarding Forward-Looking Statements and Risk Factors, in our quarterly reports on Form 10-Q or in other reports which we from time to time file with the Securities and Exchange Commission. These are available publicly on the SEC website, www.sec.gov, and on the Steel Dynamics website, www.steeldynamics.com: Investors: SEC Filings.

Contact:  Tricia Meyers, Investor Relations Manager— +1.260.969.3500

Steel Dynamics, Inc.

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