Exhibit 99.1

Press Release April 17, 2013
	7575 W. Jefferson Blvd.
	Fort Wayne, IN  46804

Steel Dynamics Reports First Quarter 2013 Diluted Earnings Per Share of $0.21

FORT WAYNE, INDIANA, April 17, 2013 / PRNewswire / Steel Dynamics, Inc. (NASDAQ/GS: STLD) today announced first quarter 2013 net income of $48 million, or $0.21 per diluted share, on net sales of $1.8 billion.  By comparison, prior year first quarter net income was $46 million, or $0.20 per diluted share, on net sales of $2.0 billion; and sequential fourth quarter 2012 net income was $61 million, or $0.27 per diluted share, on net sales of $1.7 billion.  Prior quarters included the following items—first quarter 2012 earnings were reduced by $0.03 per diluted share due to refinancing costs and fourth quarter 2012 earnings were increased by $0.07 per diluted share due to positive tax adjustments.

“The first quarter remained challenging from a market perspective, as customer confidence and buying patterns continued to be impacted by global economic uncertainty;” said President and Chief Executive Officer, Mark Millett, “but the team did a great job.  We hit several production records, and did so safely, as safety records improved from levels already better than industry standards.  We are pleased the first quarter financial performance was at the upper range of our March guidance.  Operating income improved slightly to $96 million compared to last quarter’s results.

“Compared to the fourth quarter, operating income from our steel operations improved four percent to $122 million, as increased long product volumes more than offset weaker sheet steel shipments and somewhat lower overall metal spreads,” stated Millett.  “An oversupplied northeastern U.S. galvanized sheet market pressured first quarter shipments from The Techs.  However, increased shipments of wide flange beams, rail and engineered bar products more than offset the decrease.  Despite the slow growth of the commercial construction market, we have seen increased wide flange beam shipments for several consecutive quarters, albeit still very low in relative historical terms, and our fabrication business continues to be profitable.

“Operating income from our metals recycling operations decreased three percent to $25 million when compared to the fourth quarter, as increased volumes were more than offset by decreased ferrous and nonferrous margins,” said Millett. “We noted in our fourth quarter 2012 earnings release that we were anticipating potential challenges in the metals recycling market during the first quarter 2013.  Due to ongoing slow U.S. growth and inclement weather, the availability of unprocessed scrap was limited, particularly in the Midwest and along the northeastern corridor, resulting in increased costs to purchase unprocessed material.

“The company’s continued solid performance in a difficult market environment is driven by our ongoing commitment to provide exceptional value to our customers, while taking advantage of our innovative, low-cost operating culture.  We remain committed to leveraging the full complement of our competitive strengths to sustain and grow shareholder value,” Millett concluded.

First Quarter Review

First quarter shipments were higher across the company’s operating segments when compared to the fourth quarter of 2012, and to the prior year first quarter, aside from metals recycling which decreased year over year.  Operating income increased slightly when compared to the fourth quarter of last year, but declined 20 percent from prior year’s first quarter, primarily due to reduced steel metal spreads, as steel product pricing decreased more than scrap raw material costs.

The company’s steel mill utilization rate improved to 89 percent in the first quarter from 80 percent in the fourth quarter of 2012.  There was a shift toward higher valued-added products in the company’s steel shipments during the first quarter of 2013, when compared to the fourth quarter of 2012.  This change helped offset decreased metal spread, resulting in increased operating income of $4 million.  The average

selling price per ton shipped increased $5 to $789 in the first quarter, and the average ferrous scrap cost per ton melted increased $8 per ton.   Operating income attributable to the company’s long product operations increased 16 percent when compared to the sequential quarter, while earnings from sheet operations decreased four percent.

The impact of losses from the company’s Minnesota operations on first quarter 2013 consolidated net income was approximately $14 million, or $0.06 per diluted share, which included a unique loss of $2 million (after taxes), or $0.01 per diluted share, related to the sale of excess iron concentrate reserves purchased from third parties.  In addition, despite achieving record production levels, the use of higher cost iron concentrate during the quarter also resulted in increased operating losses.  Comparatively, the impact of losses on fourth quarter 2012 earnings was $10 million, or approximately $0.04 per diluted share.  As previously indicated and according to plan, the installation of additional oxygen-burners and other equipment modifications will be made at the iron nugget facility in April.  These modifications are expected to further improve production volumes.

Production at the company’s iron concentrate facility continues to proceed well, and the plant is operating at a cash-cost of less than $50 per metric ton, which is substantially less than current market prices in excess of $135 per metric ton.  As iron concentrate is the primary raw material for the iron nugget facility, this is a pivotal achievement in lowering the raw material input cost of iron nuggets.

The company plans to start solely using its lower-cost iron concentrate for nugget production in May.  However, due to costs related to the outage, the company still anticipates second quarter 2013 losses associated with the Minnesota operations to be similar to those recorded in the fourth quarter of 2012.

During the first quarter the company issued $400 million of new 5¼% senior notes due in 2023 and offered to repay $500 million of its existing 6¾% senior notes due in 2015.  At March 31, 2013, the company had repaid $302 million of the existing senior notes, repaying the remaining amount of $198 million on April 9, 2013.  After giving effect to the April repayment, total debt decreased $100 million and liquidity remained strong with $1.4 billion in unrestricted cash and available funding under the revolving credit facility. These transactions, along with the resulting repayment of debt with available cash, not only extended the company’s overall debt maturity profile, but should also provide an estimated annual interest savings of approximately $13 million.

Outlook

“Demand for high-quality steel products has not abated,” Millett said. “We remain optimistic. The team is on track to complete the organic growth projects scheduled to start at the end of this year, including the engineered special-bar-quality capacity expansion and the premium rail product addition.  The automotive market remains strong, and we believe there is potential for manufactured goods to continue to build momentum in 2013.   Housing start data also suggests an increasingly higher potential for a recovery in residential construction. We continue to be cautiously optimistic about the nonresidential construction market in 2013, as market indices continue to trend higher. We also view the increase in our long product and fabrication sales as a positive sign, even though they are improving from historically low levels. We are confident that with our exceptional team, and our superior, low-cost operating culture, we are uniquely prepared to capitalize on the opportunities ahead.”

Summary First Quarter Operating Segment Information

The following tables highlight operating results for each of the company’s primary operating platforms. References to operating income in the following paragraphs exclude profit-sharing expenses and amortization pertaining to intangible assets.  Dollar amounts are in thousands, excluding per ton data.

Steel Operations

This segment includes five electric-arc-furnace steel mills and related steel finishing and processing facilities, including The Techs. The company’s steel operations produce flat-rolled steel, structural steel, merchant bars, engineered special-bar-quality steel, rebar, rail, and specialty shapes.

	First Quarter				Sequential
	2013		2012		4Q 2012
Total Sales	$	1,142,075	$	1,254,464	$	1,126,438
External Sales	1,061,312		1,186,720		1,061,419
Operating Income	121,589		139,740		117,097
Total Shipments (tons)	1,469,802		1,450,123		1,457,053
Average External Sales Price Per Ton	$	789	$	875	$	784
Average Ferrous Scrap Cost Per Ton	$	351	$	417	$	343

Metals Recycling and Ferrous Resources Operations

This segment principally includes the company’s metals recycling operations (OmniSource Corporation), a liquid pig iron production facility (Iron Dynamics), and the company’s Minnesota iron producing operations.

	First Quarter					Sequential
Metals Recycling & Ferrous Resources	2013			2012		4Q 2012
Total Sales	$	914,568		$	1,112,340	$	798,163
External Sales	621,128			699,600		530,258
Operating Income (Loss)	(4,309		)	10,399		507

	First Quarter						Sequential
Metals Recycling (Standalone)	2013			2012			4Q 2012
Total Sales	$	835,039		$	1,057,173		$	741,342
External Sales	609,918			699,342			520,931
Operating Income	24,965			25,004			25,818
Unrealized Hedging Gains	691			2,003			9,820
Ferrous Shipments (gross tons)	1,342,929			1,582,840			1,238,143
% Shipments to SDI Steel Mills	41		%	48		%	46		%
Nonferrous Shipments (pounds 000’s)	279,656			291,636			251,080

Steel Fabrication Operations

Steel fabrication operations include New Millennium Building Systems, which fabricates steel joists, trusses, and decking used in the construction of non-residential buildings.

	First Quarter					Sequential
	2013		2012			4Q 2012
Total Sales	$	94,375	$	74,896		$	98,301
Operating Income (Loss)	1,530		(2,668		)	1,448
Total Shipments (tons)	77,583		60,183			76,870
Average External Sales Price Per Ton	$	1,214	$	1,244		$	1,278

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 annual sales of $7.3 billion in 2012, over 6,600 employees, and manufacturing facilities primarily located throughout the United States (including five steel mills, six steel processing facilities, two iron production facilities, over 70 metals recycling locations and six steel fabrication plants).

Forward-Looking Statement

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 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 a recurrent slowing economy on industrial demand; (2) changes in economic conditions, either generally or in any of the steel or scrap-consuming sectors which affect demand for our products, including the strength of the non-residential and residential construction, automotive, appliance, and other steel-consuming industries; (3) 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; (4) the impact of domestic and foreign import price competition; (5) risks and uncertainties involving product and/or technology development; and (6) occurrences of unexpected plant outages or equipment failures.

More specifically, we refer you to SDI’s 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, 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 Web site, www.sec.gov, and on the Steel Dynamics Web site, www.steeldynamics.com.

Conference Call and Webcast

On Thursday, April 18, 2013, at 10:00 a.m. Eastern Time, Steel Dynamics will host a conference call with investors and analysts to discuss the company’s first quarter 2013 operating and financial results.  We invite you to listen to the live audiocast of the conference call accessible from our website (http://www.steeldynamics.com), or via telephone (the conference call number may also be obtained on our website).   A replay of the discussion will be available on our website until midnight on  April 25, 2013.  A downloadable podcast and an MP3 file of the event will also be available on our website.

Contact:  Marlene Owen, Director Investor Relations —+1.260.969.3500

Steel Dynamics, Inc.

CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)

(in thousands, except per share data)

	Three Months Ended					Three Months Ended
	March 31,					December 31,
	2013			2012		2012
Net sales	$	1,795,696		$	1,982,040	$	1,705,001
Costs of goods sold	1,619,432			1,780,776		1,524,904
Gross profit	176,264			201,264		180,097
Selling, general and administrative expenses	65,262			64,384		69,340
Profit sharing	6,643			8,072		6,750
Amortization of intangible assets	8,127			8,992		8,722
Impairment charges	—			—		356
Operating income	96,232			119,816		94,929
Interest expense, net of capitalized interest	34,629			41,112		34,877
Other expense (income), net	(1,046		)	10,248		(3,852		)
Income before income taxes	62,649			68,456		63,904
Income taxes	21,397			26,679		8,810
Net income	41,252			41,777		55,094
Net loss attributable to noncontrolling interests	6,963			3,898		5,477
Net income attributable to Steel Dynamics, Inc.	$	48,215		$	45,675	$	60,571
Basic earnings per share attributable to Steel Dynamics, Inc. stockholders	$	.22		$	.21	$	.28
Weighted average common shares outstanding	219,995			218,996		219,346
Diluted earnings per share attributable to Steel Dynamics, Inc. stockholders, including the effect of assumed conversions when dilutive	$	.21		$	.20	$	.27
Weighted average common shares and equivalents outstanding	238,087			236,526		236,890
Dividends declared per share	$	.11		$	.10	$	.10

Steel Dynamics, Inc.

UNAUDITED SUPPLEMENTAL OPERATING INFORMATION

(dollars in thousands)

	Quarter Ended						Quarter Ended
	March 31,						December 31,
	2013			2012			2012
Steel Operations*
Shipments (tons)
Flat Roll Division	704,290			658,505			713,770
Structural and Rail Division
Structural	228,089			227,059			225,100
Rail	52,808			33,947			37,341
Engineered Bar Products Division	112,821			157,489			98,858
Roanoke Bar Division	139,950			151,296			127,952
Steel of West Virginia	80,707			77,212			73,581
The Techs	151,137			144,615			180,451
Total	1,469,802			1,450,123			1,457,053
Intra-company	(125,370		)	(94,176		)	(102,772		)
External	1,344,432			1,355,947			1,354,281
Production, excluding The Techs (tons)	1,407,508			1,351,818			1,290,567
Net sales
Total	$	1,142,075		$	1,254,464		$	1,126,438
Intra-company	(80,763		)	(67,744		)	(65,019		)
External	$	1,061,312		$	1,186,720		$	1,061,419
Operating income before amortization of intangibles	$	121,589		$	139,740		$	117,097
Amortization of intangibles	(2,288		)	(2,432		)	(2,289		)
Operating income (Note 1)	$	119,301		$	137,308		$	114,808
Metals Recycling and Ferrous Resources Operations**
OmniSource
Ferrous metals shipments (gross tons)
Total	1,342,929			1,582,840			1,238,143
Intra-company	(553,890		)	(763,767		)	(573,293		)
External	789,039			819,073			664,850
Nonferrous metals shipments (thousands of pounds)
Total	279,656			291,636			251,080
Intra-company	(3,529		)	(1,958		)	(3,456		)
External	276,127			289,678			247,624
Mesabi Nugget shipments (metric tons) - Intra-company	59,685			46,230			36,481
Iron Dynamics (metric tons) - Intra-company	64,685			56,628			57,117
Net sales
Total	$	914,568		$	1,112,340		$	798,163
Intra-company	(293,440		)	(412,740		)	(267,905		)
External	$	621,128		$	699,600		$	530,258
Operating income (loss) before amortization of intangibles	$	(4,309	)	$	10,399		$	507
Amortization of intangibles	(5,515		)	(6,236		)	(6,110		)
Operating income (loss) (Note 1)	$	(9,824	)	$	4,163		$	(5,603	)
Steel Fabrication Operations***
Shipments (tons)
Total	77,583			60,183			76,870
Intra-company	(334		)	(2		)	(187		)
External	77,249			60,181			76,683
Net sales
Total	$	94,375		$	74,896		$	98,301
Intra-company	(578		)	(4		)	(277		)
External	$	93,797		$	74,892		$	98,024
Operating income (loss) (Note 1)	$	1,530		$	(2,668	)	$	1,448

*	Steel Operations include the company’s five steelmaking divisions and The Techs three galvanizing plants.
**	Metals Recycling and Ferrous Resources Operations include OmniSource; Iron Dynamics (all shipments are internal); and Minnesota Operations, including Mesabi Nugget (all shipments have been internal).
***	Steel Fabrication Operations include the company’s joist and deck fabrication operations.

(Note 1) Segment operating income (loss) excludes profit sharing expense.

Steel Dynamics, Inc.

CONSOLIDATED BALANCE SHEETS

(in thousands)

	March 31, 2013			December 31, 2012
	(unaudited)
Assets
Current assets
Cash and equivalents	$	477,861		$	375,917
Investments in short-term commercial paper	—			31,520
Accounts receivable, net	753,301			642,363
Inventories	1,170,159			1,202,507
Deferred income taxes	23,564			23,449
Income taxes receivable	412			893
Other current assets	23,644			19,576
Total current assets	2,448,941			2,296,225
Property, plant and equipment, net	2,232,413			2,231,198
Restricted cash	23,400			27,749
Intangible assets, net	408,832			416,635
Goodwill	736,912			738,542
Other assets	106,076			105,067
Total assets	$	5,956,574		$	5,815,416
Liabilities and Equity
Current liabilities
Accounts payable	$	410,632		$	360,097
Income taxes payable	13,438			16,941
Accrued expenses	159,035			203,008
Current maturities of long-term debt	231,582			29,631
Total current liabilities	814,687			609,677
Long-term debt
Term note	240,625			247,500
Senior notes	1,500,000			1,600,000
Convertible senior notes	287,496			287,496
Other long-term debt	41,093			37,610
Total long-term debt	2,069,214			2,172,606
Deferred income taxes	546,722			537,304
Other liabilities	19,947			19,173
Commitments and contingencies
Redeemable noncontrolling interests	99,414			98,814
Equity
Common stock	639			637
Treasury stock, at cost	(719,076		)	(720,479		)
Additional paid-in capital	1,045,973			1,037,687
Retained earnings	2,111,597			2,087,620
Total Steel Dynamics, Inc. equity	2,439,133			2,405,465
Noncontrolling interests	(32,543		)	(27,623		)
Total equity	2,406,590			2,377,842
Total liabilities and equity	$	5,956,574		$	5,815,416

Steel Dynamics, Inc.

CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)

(in thousands)

	Three Months Ended
	March 31,
	2013			2012
Operating activities:
Net income	$	41,252		$	41,777
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	57,061			55,572
Equity-based compensation	4,753			6,123
Deferred income taxes	10,935			9,197
Changes in certain assets and liabilities:
Accounts receivable	(110,938		)	(60,820		)
Inventories	32,348			(55,090		)
Accounts payable	38,988			34,902
Income taxes receivable/payable	(3,022		)	17,392
Other assets and liabilities	(41,667		)	(27,632		)
Net cash provided by operating activities	29,710			21,421
Investing activities:
Purchase of property, plant and equipment	(45,346		)	(45,555		)
Other investing activities	33,934			(1,864		)
Net cash used in investing activities	(11,412		)	(47,419		)
Financing activities:
Issuance of current and long-term debt	409,261			289,969
Repayment of current and long-term debt	(305,691		)	(283,448		)
Debt issuance costs	(5,997		)	(2,191		)
Proceeds from exercise of stock options, including related tax effect	7,614			1,097
Contributions from noncontrolling investors, net	411			9,506
Dividends paid	(21,952		)	(21,887		)
Net cash provided by (used in) financing activities	83,646			(6,954		)
Increase (decrease) in cash and equivalents	101,944			(32,952		)
Cash and equivalents at beginning of period	375,917			390,761
Cash and equivalents at end of period	$	477,861		$	357,809
Supplemental disclosure information:
Cash paid for interest	$	49,732		$	18,753
Cash paid (received) for federal and state income taxes, net	$	11,165		$	(955	)