Steel Dynamics (STLD) 10-K risk factor changes: FY2025 vs FY2024

Our [removed: industry,] [added: industries,] as well as the industries of many of our customers and suppliers upon whom we are dependent, [removed: is] [added: are] affected by domestic and global economic factors including periods of slower than anticipated economic growth and the risk of a recession.

Global or domestic actions or conditions, including political actions, proposed or actual trade policies or restrictions, including tariffs or quotas, proposed or actual changes in tax laws, including the [added: imposition of new tax laws or] sunset of certain tax laws, proposed or actual regulation, including those related to the environment, interest rates, terrorism, acts of war or hostility, natural disasters, or pandemics, epidemics, widespread illness or other health issues, could result in changing economic conditions in the United States and globally, disruptions to or slowdowns in our business, our supply chain, or our global or domestic [removed: industry,] [added: industries,] or those of our customers or suppliers upon whom we are dependent.

Our business is also dependent upon certain industries, such as construction, automotive, manufacturing, transportation, heavy and [removed: agriculture] [added: agricultural] equipment, [removed: energy] [added: energy, food packaging, beverage can] and pipe and tube (including OCTG) markets, and [added: many of] these industries are also cyclical in nature and may experience supply chain disruptions.

As a result of volatility in our [removed: industry] [added: industries] or in the industries we serve, we may have difficulty increasing or maintaining our level of sales or profitability.

A downturn in our [removed: industry] [added: industries] or the industries we serve may adversely affect our business, results of operations, financial condition and cash flows.

A disruption of the credit markets could also result in financial instability [removed: of] [added: for] some of our customers and suppliers.

Our [added: steel operations financial condition,] results of operations, [removed: financial condition] and cash flows are driven primarily from the metal spread achieved from the price we sell steel and steel products compared to the price of our metallic raw materials, including scrap.

Should current or new tariffs, duties or quotas expire or be relaxed, repealed or circumvented by importers of steel and steel products, or should trade agreements be renegotiated, downward pressure may be exerted on United States steel and steel products prices, which may adversely affect our [added: steel] business, results of operations, financial condition and cash flows.

Our level of production and our sales and earnings are subject to significant fluctuations as a result of the cyclical nature of the [removed: steel industry] [added: metals industries] and some of the [added: other] industries we serve.

The steel [added: and aluminum] manufacturing business is cyclical in nature, and the selling price of the [removed: steel] [added: products] we make may fluctuate significantly due to many factors beyond our control.

The sale of our manufactured steel [added: and aluminum] products is directly affected by demand for our products in other cyclical industries, such as construction, automotive, manufacturing, transportation, heavy and [removed: agriculture] [added: agricultural] equipment, [removed: energy] [added: energy, food packaging, beverage can] and pipe and tube (including OCTG) markets.

Economic difficulties, stagnant or slow global economies, supply and demand imbalances, supply chain disruptions, periods of heightened inflation or high interest rates, and currency fluctuations in the United States or globally may decrease the demand for our products or increase the amount of imports of steel [added: or aluminum] into the United States, which may decrease our sales, margins and profitability.

Steel [added: and aluminum] producers require large amounts of raw materials, including ferrous [added: and aluminum] scrap metal and scrap substitute products such as pig iron and pelletized iron, and other supplies such as zinc, graphite electrodes and ferroalloys.

The principal raw [removed: material] [added: materials] of our EAF steel operations [removed: is] [added: and aluminum operations are] recycled [removed: ferrous] scrap derived from, among other sources, “home scrap,” generated internally at steel [added: and aluminum] mills themselves; industrial scrap, generated as a by-product of manufacturing; obsolete scrap, recycled from end-of-life automobiles, [removed: appliances] [added: appliances, machinery, food packaging] and [removed: machinery;] [added: used beverage cans;] and demolition scrap, recycled from obsolete structures, containers and machines.

The prices for scrap are subject to market forces largely beyond our control, including demand by United States and foreign steel [added: and aluminum] producers, freight costs and speculation.

The scrap metal recycling industry has historically been, and is expected to remain, highly cyclical and the prices for scrap have varied significantly in the past, may vary significantly in the future and do not necessarily fluctuate in tandem with the price of [removed: steel.][added: steel and aluminum.]

However, given environmental considerations of investors, customers and regulators, additional EAF mills may be constructed, or companies currently operating blast furnace mills may invest in EAF mills, leading to increased demand in ferrous scrap possibly resulting in higher [added: ferrous] scrap prices.

While our vertical integration [removed: into the] [added: with our] metals recycling business and [removed: our] liquid pig-iron operations are expected to enable us to continue being a cost-effective supplier to our own steelmaking [added: and aluminum] operations, for some of our metallics requirements, we still rely on other metallics and raw material suppliers, as well as upon general industry supply conditions for the balance of our needs.

The availability and prices of raw materials and supplies, particularly those with positive environmental attributes, may also be negatively affected by new, existing or changing laws, regulations, sanctions or embargoes, including those that may impose output limitations or higher costs associated with climate change or GHG allocation by suppliers, interruptions in production, accidents or natural disasters, changes in exchange rates, global price fluctuations, the availability and cost of transportation, and competing uses, all of which may be [removed: heighted] [added: heightened] during times of war or hostilities.

Prolonged blackouts, curtailments or disruptions caused [removed: by] [added: by, among other things,] natural disasters or by political or environmental considerations would substantially disrupt our production.

We are taking further action to reduce our environmental footprint through our [removed: 2025, 2030,] [added: 2030] and 2050 goals for GHG emission reduction and increased renewable energy usage.

To achieve these goals, our operational costs may [removed: increase] [added: increase,] and we have had and will continue to have additional capital expenditures, some of which we may not be able to pass along to our customers.

[removed: ●the] [added: | | ● | the] generation, storage, treatment, handling and disposal of solid and hazardous wastes and secondary materials; [added: |]

●the use and treatment of [removed: groundwater;][added: groundwater and surface water;]

●the remediation of [added: equipment, product,] soil [removed: and groundwater] [added: or water] contamination;

●the remediation and reclamation of land used in [added: or affected by] our operations;

Compliance with environmental laws and regulations, which affect our EAF steelmaking, metals recycling, liquid pig-iron, [added: aluminum,] and copper [removed: and aluminum] production operations, is a significant factor in our business.

[removed: We are required to obtain] and comply with environmental permits and licenses, and failure to obtain or renew or the violation of any permit or license may result in substantial fines and penalties, capital expenditures, operational changes, suspension of operations or the closure of a subject facility.

Uncertainty regarding [removed: adequate] [added: appropriate] pollution control levels, testing and sampling procedures, and new pollution control technology are factors that may increase our future compliance expenditures.

In practice, a liable party often splits the costs of cleanup with other [added: potentially responsible parties.]

The global markets in which steel [added: and aluminum] companies and scrap processors conduct business are highly competitive and became even more so due to consolidations in [removed: the steel and scrap] [added: these] industries.

Additionally, in many applications, steel [removed: competes] [added: and aluminum compete] with other materials, such as [removed: aluminum,] [added: aluminum or steel, as the case may be,] cement, composites, plastics, carbon fiber, [removed: glass] [added: titanium, tin, glass, wood,] and [removed: wood.][added: paperboard.]

Increased use of alternative materials for any reason, including as a response to regulations or customer demands, could decrease demand for steel [added: and aluminum] or force other [removed: steel] producers into new products or markets that compete more directly with us, and combined with increased competition could cause us to lose market share, increase expenditures or reduce pricing, any one of which may adversely affect our business, financial condition, results of operations and cash flows.

In addition, a slowdown of industrial [added: or other scrap sources, such as used beverage cans,] production in the United States reduces the supply of industrial grades of metal to the metals recycling industry, resulting in our having less recyclable metal available to [removed: process and sell.][added: process, sell, or consume for our steelmaking or aluminum operations.]

Further, additional EAF steel mill [added: or aluminum production facility] construction or blast furnace mills investing in EAF mills could increase the demand for [added: ferrous and aluminum] scrap, potentially resulting in higher scrap prices or periods of decreased scrap supply.

Any inability to secure scrap for our [removed: EAF steel mills] [added: steelmaking and aluminum operations] could adversely affect our business, results of operations, financial condition and cash flows.

Additionally, cybersecurity vulnerabilities or attacks could result in an interruption of the functionality of our automated and electronically controlled manufacturing operating systems, which, if compromised, could cease, threaten, delay or slow down our ability to melt, roll or otherwise process [added: steel, aluminum or any of our other products for the duration of such interruption.]

This could lead to system interruption, production delays or downtimes and operational disruptions, and the disclosure, modification or destruction of sensitive data, which may adversely affect our reputation, customer and supplier relationships, financial results and results of operations, and could result in litigation or regulatory investigations, actions, fines or penalties, as well as increased cybersecurity monitoring [removed: and protection costs, including the cost or availability of insurance.]

● the risk of a newly constructed facility being completed over budget or not on time, including due to equipment delays or labor shortages, or having delays or difficulties with its [removed: start-up;][added: start-up, ramp-up or qualification of products;]

● the risk of new product [removed: development,] [added: development and qualification,] technology development or customer acquisition and penetration being more [removed: costly] [added: costly, time-consuming] or difficult than expected;

Additionally, the construction of any new aluminum flat rolled products mills may also lead to increased demand in aluminum scrap possibly resulting in higher aluminum scrap prices.

| --- | --- | --- |

We are required to obtain

and protection costs, including the cost or availability of insurance.

These expansions and transactions may involve some or all of the following risks:

Delayed delivery of our products to customers who require on-time delivery from us may cause customers to purchase alternative products, reschedule their own production, or incur other incremental costs.

Customers may be able to pursue financial claims against us for their incremental costs, and we may incur costs to correct such problems in addition to any liability resulting from such

claims.

Interruptions may also harm our reputation among actual and potential customers, potentially resulting in a loss of business.

We may experience difficulties in the launch or production ramp-up of new products which may adversely affect our business.

As we ramp up manufacturing processes for newly introduced products, we may experience difficulties, including manufacturing disruptions, delays, or other complications, which could adversely affect our ability to serve our customers, our reputation, our costs of production and, ultimately, our business, financial condition, results of operations and cash flows.

Our aluminum operations depend on a core group of significant customers.

We have a relatively concentrated group of aluminum customers.

Most of these customers have one or more sizable sales agreements with us.

If one or more of these customers experienced a prolonged period of adverse demand, depressed business activity or financial distress, if any of these customers breached or sought relief from its contractual obligations under its sales agreements with us or if any of these customer relationships otherwise ended or materiality deteriorated and such lost business was not successfully replaced, our aluminum operations financial condition, results of operations, and cash flows may be adversely affected.

Additionally, at times when iron ore prices are low, disruption of the scrap price correlation to iron ore may occur, which may lead to reduced global costs to produce steel, further depressing steel import prices.

Pandemics, epidemics, widespread illness or other health issues may adversely affect our business, results of operations, financial condition, cash flows, liquidity, and stock price.

Pandemics, epidemics, widespread illness or other health issues may adversely affect our business, results of operations, financial condition, cash flows, liquidity and stock price.

Government actions globally, including United States federal and state governmental actions, related to pandemics, epidemics, widespread illness or other health issues have historically impacted demand for our products, our supply chain, our employees, the economy generally, inflation and interest rates, and any similar future actions may result in similar or additional impacts.

As a major producer of galvanized steel products, we purchase and consume a large amount of zinc, which if purchased at high prices, may adversely affect our profit margins.

potentially responsible parties.

Additionally, our recycled aluminum flat rolled products mill with an anticipated annual production capacity of 650,000 metric tons of finished products located in Columbus, Mississippi is expected to produce commercially viable products by mid-year 2025.

Although we anticipate being able to effectively compete in the aluminum industry, along with the other risks described herein, including delays or difficulties with our start-up, we may face unexpected and enhanced competition, which may adversely affect the expected contributions of our aluminum operations and our resulting business, financial condition, results of operations and cash flows.

steel or any of our other products for the duration of such interruption.

These expansions and transactions, including our recycled aluminum flat rolled products mill with an anticipated annual production capacity of 650,000 metric tons of finished products located in Columbus, Mississippi, may involve some or all of the following risks:

Some factors that could cause such forward-looking statements to turn out differently than anticipated include: (1) domestic and global economic factors; (2) global steelmaking overcapacity and imports of steel, together with increased scrap prices; (3) [removed: pandemics, epidemics, widespread illness or other health issues; (4)] the cyclical nature of the [removed: steel industry] [added: metals industries] and the industries we serve; [removed: (5)] [added: (4)] volatility and major fluctuations in prices and availability of scrap metal, scrap substitutes and supplies, and our potential inability to pass higher costs on to our customers; [removed: (6)] [added: (5)] cost and availability of electricity, natural gas, oil, and other energy resources are subject to volatile market conditions; [removed: (7)] [added: (6)] increased environmental, greenhouse gas emissions and sustainability considerations from our customers and investors or related regulations; [removed: (8)] [added: (7)] compliance with and changes in environmental and remediation requirements; [removed: (9)] [added: (8)] significant price and other forms of competition from other steel and aluminum producers, scrap processors and alternative materials; [removed: (10)] [added: (9)] availability of an adequate source of supply of scrap for our metals recycling operations; [removed: (11)] [added: (10)] cybersecurity threats and risks to the security of our sensitive data and information technology; [removed: (12)] [added: (11)] the implementation of our growth strategy; [removed: (13)] [added: (12)] our ability to retain, develop and attract key personnel; [removed: (14)] [added: (13)] litigation and legal compliance; [removed: (15)] [added: (14)] unexpected equipment downtime or shutdowns; [added: (15) difficulties in the launch or production ramp-up of new products;] (16) [added: our aluminum operations depend on a core group of significant customers; (17)] governmental agencies may refuse to grant or renew some of our licenses and permits; [removed: (17)] [added: (18)] our [removed: senior unsecured credit facility contains,] [added: existing debt agreements contain,] and any future financing agreements may contain, restrictive covenants that may limit our flexibility; and [removed: (18)] [added: (19)] the impacts of impairment charges.

We charge premium prices for certain grades of [removed: steel,] [added: steel and aluminum,] product dimensions, certain smaller volumes, and for value-added processing or coating of our steel products.

Consolidated net sales were [removed: $17.5] [added: $18.2] billion during [removed: 2024,] [added: 2025,] with cash flow from operations of [removed: $1.8] [added: $1.4] billion.

Metal spread compression in our steel and, particularly, steel fabrication segments resulted in [removed: significantly] lower operating income in [removed: 2024] [added: 2025] compared to [removed: 2023.][added: 2024.]

Consolidated operating income for [removed: 2024] [added: 2025] decreased [removed: $1.2 billion,] [added: $467.1 million,] or [removed: 38%,] [added: 24%,] to [removed: $1.9] [added: $1.5] billion, compared to [removed: $3.2] [added: $1.9] billion in [removed: 2023.][added: 2024.]

Net income attributable to Steel Dynamics, Inc. for [removed: 2024] [added: 2025] decreased [removed: $913.7] [added: $351.5] million, or [removed: 37%,] [added: 23%,] to [removed: $1.5] [added: $1.2] billion, compared to [removed: 2023.][added: 2024.]

Diluted earnings per share attributable to Steel Dynamics, Inc. was [removed: $9.84] [added: $7.99] for [removed: 2024,] [added: 2025,] compared to [removed: $14.64] [added: $9.84] for [removed: 2023.][added: 2024.]

_Management’s Discussion and Analysis of Financial Condition and Results of Operations_ in Part II of our Annual Report on Form 10-K for the year ended December 31, [removed: 2023,] [added: 2024,] for additional information regarding results of operations for the year ended December 31, [removed: 2023,] [added: 2024,] as compared to the year ended December 31, [removed: 2022,] [added: 2023,] and segment operating results for [removed: 2023] [added: 2024] as compared to [removed: 2022.][added: 2023.]

| ​ | ​ | [removed: 2024] [added: 2025] | | ​ | % Change | ​ | [removed: 2023] [added: 2024] | | ​ |

| ​ | Steel Operations | $ | [removed: 12,527,066] [added: 13,412,773] | ​ | [removed: (4)%] [added: 7%] | ​ | $ | [removed: 13,067,622] [added: 12,527,066] | ​ |

| ​ | Metals Recycling Operations | ​ | [removed: 4,136,913] [added: 4,346,074] | ​ | [removed: (1)%] [added: 5%] | ​ | ​ | [removed: 4,158,588] [added: 4,136,913] | ​ |

| ​ | Steel Fabrication Operations | ​ | [removed: 1,771,795] [added: 1,418,665] | ​ | [removed: (37)%] [added: (20)%] | ​ | ​ | [removed: 2,806,777] [added: 1,771,795] | ​ |

| ​ | Aluminum Operations | ​ | [removed: 318,689] [added: 473,881] | ​ | [removed: 11%] [added: 49%] | ​ | ​ | [removed: 285,907] [added: 318,689] | ​ |

| ​ | Steel Operations | $ | [removed: 1,582,374] [added: 1,427,544] | ​ | [removed: (16)%] [added: (10)%] | ​ | $ | [removed: 1,881,600] [added: 1,582,374] | ​ |

| ​ | Metals Recycling Operations | ​ | [removed: 76,807] [added: 97,176] | ​ | [removed: 61%] [added: 27%] | ​ | ​ | [removed: 47,735] [added: 76,807] | ​ |

| ​ | Steel Fabrication Operations | ​ | [removed: 666,984] [added: 407,425] | ​ | [removed: (58)%] [added: (39)%] | ​ | ​ | [removed: 1,593,261] [added: 666,984] | ​ |

Steel operations include our [removed: EAF] [added: electric arc furnace (EAF)] steel mills, including Butler Flat Roll Division, Columbus Flat Roll Division, Southwest-Sinton Flat Roll Division, Structural and Rail Division, Engineered Bar Products Division, Roanoke Bar Division, [added: and] Steel of West [removed: Virginia,] [added: Virginia;] steel coating and processing operations at The Techs, Heartland Flat Roll Division, United Steel Supply, [added: New Process Steel, L.P. (acquired December 1, 2025), and] Vulcan Threaded Products, [removed: Inc.,] [added: Inc.;] warehouse operations in [removed: Mexico,] [added: Mexico;] and [added: a 75% controlling equity interest in] SDI Biocarbon Solutions, [removed: LLC, a joint venture to construct and operate a biocarbon production facility.][added: LLC.]

Steel operations accounted for [removed: 69%] [added: 72%] and [removed: 67%] [added: 69%] of our consolidated net sales during [removed: 2024] [added: 2025] and [removed: 2023,] [added: 2024,] respectively.

Steel Operations [added: Segment] Shipments (tons):

| ​ | ​ | [removed: 2024] [added: 2025] | ​ | % Change | ​ | [removed: 2023] [added: 2024] | ​ |

| ​ | Total shipments | [removed: 12,660,487] [added: 13,748,801] | ​ | [removed: (1)%] [added: 9%] | ​ | [removed: 12,821,753] [added: 12,660,487] | ​ |

| ​ | Intra-segment shipments | [removed: (1,306,364)] [added: (1,429,299)] | ​ | ​ | ​ | [removed: (1,449,832)] [added: (1,306,364)] | ​ |

| ​ | Steel Operations Segment shipments | [removed: 11,354,123] [added: 12,319,502] | ​ | [removed: \-] [added: 9%] | ​ | [removed: 11,371,921] [added: 11,354,123] | ​ |

| ​ | External shipments | [removed: 10,929,453] [added: 11,960,582] | ​ | [removed: \-] [added: 9%] | ​ | [removed: 10,976,707] [added: 10,929,453] | ​ |

[removed: ][added: ]

[added: Steel Operations] Segment Results [removed: 2024] [added: 2025] vs. [removed: 2023][added: 2024]

Net sales for the steel operations segment were [removed: 4% lower] [added: 7% higher] in [removed: 2024] [added: 2025] when compared to [removed: 2023,] [added: 2024,] due to [removed: lower average steel selling prices on consistent volumes.][added: a 9% increase in segment shipments.]

Our metallic raw material cost consumed in our steel mills [removed: decreased $28] [added: was unchanged on a] per net [removed: ton, or 7%,] [added: ton basis] in [removed: 2024] [added: 2025] compared to [removed: 2023,] [added: 2024,] consistent with overall [removed: decreased] [added: steady] domestic scrap pricing noted below in the metals recycling operations segment discussion.

As a result of average selling prices decreasing more than scrap costs, [removed: specifically for long products,] metal spread (which we define as the difference between average steel mill selling prices and the cost of ferrous scrap consumed in our steel mills) decreased [removed: 3%] [added: 2%] in [removed: 2024] [added: 2025] compared to [removed: 2023.][added: 2024.]

Due to metal spread compression, operating income for the steel operations decreased [removed: 16%] [added: 10%] to [removed: $1.6] [added: $1.4] billion in [removed: 2024] [added: 2025] compared to [removed: 2023.][added: 2024.]

Metals recycling operations include our [removed: OmniSource] [added: Omni] ferrous and nonferrous processing, transportation, marketing, brokerage, and scrap management services [removed: primarily] [added: located] throughout the United States and [added: in Central and Northern] Mexico.

In [removed: 2024] [added: 2025] and [removed: 2023, 62%] [added: 2024, 65% and 62%, respectively,] of metals recycling operations ferrous scrap was sold to our own steel mills, [removed: while] [added: as] our steel mill utilization [removed: remained consistent at 81% and 82%] [added: increased to 86%] in [removed: 2024 and 2023, respectively.][added: 2025 compared to 81% 2024, with production levels at our Sinton facility increasing during 2025.]

Metals recycling operations accounted for 11% of our consolidated net sales during [removed: 2024] [added: 2025] and [removed: 2023.][added: 2024.]

Metals Recycling Operations [added: Segment] Shipments:

| ​ | ​ | ​ | [removed: 2024] [added: 2025] | ​ | % Change | ​ | [removed: 2023] [added: 2024] | ​ |

| ​ | Total | ​ | [removed: 5,850,544] [added: 6,160,797] | ​ | [removed: 1%] [added: 5%] | ​ | [removed: 5,792,484] [added: 5,850,544] | ​ |

| ​ | External shipments | ​ | [removed: 2,194,510] [added: 2,147,762] | ​ | [removed: \-] [added: (2)%] | ​ | [removed: 2,199,156] [added: 2,194,510] | ​ |

| ​ | Total | ​ | [removed: 965,491] [added: 916,502] | ​ | [removed: (1)%] [added: (5)%] | ​ | [removed: 970,445] [added: 965,491] | ​ |

| ​ | External shipments | ​ | [removed: 793,576] [added: 737,786] | ​ | [removed: 4%] [added: (7)%] | ​ | [removed: 762,579] [added: 793,576] | ​ |

During [removed: 2024,] [added: 2025,] our metals recycling operations continued to benefit from solid domestic steel industry demand, resulting in [removed: consistent] [added: increased] ferrous [removed: and nonferrous] scrap shipments compared to [removed: 2023.][added: 2024.]

2025 Overview

During 2025 we achieved record steel shipments of 13.7 million tons.

Underlying domestic steel demand was stable during 2025, as imports declined from the elevated levels experienced during the first half of the year and as the Sinton Flat Roll Division’s year-over-year operating performance improved.

Our metals recycling operations segment achieved notable improvement in operating income in 2025 compared to 2024 on higher ferrous metals volumes and higher ferrous and nonferrous pricing.

Our steel fabrication operations experienced historically strong, yet moderating product pricing compared to 2024, with stabilization in selling values realized in the fourth quarter of 2025.

Finally, our aluminum operations segment achieved successful production and qualifications of industrial, beverage can, and automotive quality flat rolled aluminum products, with shipments commencing in the late second half of 2025.

| ​ | Other | ​ | 1,335,454 | ​ | (8)% | ​ | ​ | 1,451,723 | ​ |

| ​ | ​ | ​ | 20,986,847 | ​ | ​ | ​ | ​ | 20,206,186 | ​ |

| ​ | Inter-segment | ​ | (2,810,266) | ​ | ​ | ​ | ​ | (2,665,796) | ​ |

| ​ | ​ | $ | 18,176,581 | ​ | 4% | ​ | $ | 17,540,390 | ​ |

| ​ | Aluminum Operations | ​ | (172,970) | ​ | (139)% | ​ | ​ | (72,331) | ​ |

| ​ | Other | ​ | (281,851) | ​ | 11% | ​ | ​ | (317,408) | ​ |

| ​ | ​ | ​ | 1,477,324 | ​ | ​ | ​ | ​ | 1,936,426 | ​ |

| ​ | Inter-segment | ​ | (1,338) | ​ | ​ | ​ | ​ | 6,611 | ​ |

| ​ | ​ | $ | 1,475,986 | ​ | (24)% | ​ | $ | 1,943,037 | ​ |

During 2025, our steel operations achieved record annual shipments of 13.7 million tons (12.3 million excluding intra-segment), 9% higher than 2024 shipments, primarily due to significant sales volume increases at our Sinton and Heartland facilities as the four new value-added lines operated for a full year in 2025.

Customer order activity and steel demand were strong during 2025, particularly as imports declined in the latter half of the year.

Demand was supported by manufacturing onshoring, infrastructure program funding, lower interest rates, and the increasing regionalization of supply chains in the US.

Despite these favorable market demand conditions, in the face of trade policy uncertainty, average selling prices were modestly lower during 2025 compared to 2024.

Steel segment average selling prices decreased 1%, or $14 per ton, compared to 2024.

| ​ | Inter-segment | ​ | (4,013,035) | ​ | ​ | ​ | (3,656,034) | ​ |

| ​ | Inter-segment | ​ | (178,716) | ​ | ​ | ​ | (171,915) | ​ |

Metals Recycling Operations Segment Results 2025 vs. 2024

Net sales for our metals recycling operations in 2025 increased 5% compared to 2024, driven by increased ferrous volumes and increased selling prices for both ferrous and nonferrous metals.

Ferrous and nonferrous scrap average selling prices increased 2% and 7%, respectively, during 2025 compared to 2024.

Ferrous shipments increased 5% and nonferrous shipments decreased 5% in 2025 compared to 2024.

As a result of these volume and metal spread changes, metals recycling operations operating income in 2025 of $97.2 million increased 27% from 2024.

Steel Fabrication Operations Segment Results 2025 vs. 2024

Order activity remained strong during 2025, with our order backlog maintaining solid levels and extending through the first half of 2026, supported by stable and historically strong pricing.

Demand was largely driven by the commercial, data center, manufacturing, warehouse, and healthcare sectors.

Lower selling prices per ton offset decreased steel input costs per ton,

The recycled aluminum flat roll products mill produces flat rolled aluminum products from aluminum scrap and is a complementary extension of the company’s metals recycling platform.

Our product offerings will be supported by various value-added finishing lines that are still under construction, including two CASH (Continuous Annealing Solutions Heat Treating) lines, a can end and tab coating line, and downstream processing and packaging lines.

Aluminum operations accounted for 2% and 1% of our consolidated net sales during 2025 and 2024, respectively.

Aluminum Operations Segment Results 2025 vs. 2024

During 2025, the results of this segment largely consisted of sales from the ancillary recycled aluminum deox-rod facility, as well as construction, start-up, and commissioning costs associated with the recycled aluminum flat roll products mill and satellite recycled aluminum slab centers.

The flat rolled products mill shipped 15,000 metric tons of finished product during the second half of 2025.

In 2025, aluminum operations sales, including those of our ancillary recycled aluminum deox-rod facility, totaled $473.9 million, an increase of 49%, compared to $318.7 million in 2024 primarily due to the volumes from the aluminum flat rolled products mill beginning in the second half of 2025.

| Consolidated Results |

This increase is primarily a result of higher outstanding long-term debt balances during 2025 compared to 2024 due to our issuance of senior unsecured notes in March and November 2025.

2024 Overview

During 2024 we achieved steel shipments of 12.7 million tons, our second highest annual volume behind 2023’s 12.8 million tons.

Underlying domestic steel demand was stable during 2024, but imports of certain steel products, most notably coated flat rolled steels, caused pricing pressure for flat rolled steel products.

While facing a challenging pricing environment throughout much of the year, our metals recycling teams maintained consistent volumes during 2024 compared to 2023.

A solid non-residential construction market during 2024 benefited our steel fabrication operations, as the segment achieved historically strong volumes and average selling prices, compared to pre-Covid levels.

Our 2024 change in reportable segments did not change the discussion previously provided.

Refer to the Aluminum Operations segment discussion for additional information.

| ​ | Other | ​ | 1,451,723 | ​ | 24% | ​ | ​ | 1,171,901 | ​ |

| ​ | ​ | ​ | 20,206,186 | ​ | ​ | ​ | ​ | 21,490,795 | ​ |

| ​ | Intra-company | ​ | (2,665,796) | ​ | ​ | ​ | ​ | (2,695,479) | ​ |

| ​ | ​ | $ | 17,540,390 | ​ | (7)% | ​ | $ | 18,795,316 | ​ |

| ​ | Aluminum Operations | ​ | (72,331) | ​ | (522)% | ​ | ​ | 17,146 | ​ |

| ​ | Other | ​ | (317,408) | ​ | 20% | ​ | ​ | (394,577) | ​ |

| ​ | ​ | ​ | 1,936,426 | ​ | ​ | ​ | ​ | 3,145,165 | ​ |

| ​ | Intra-company | ​ | 6,611 | ​ | ​ | ​ | ​ | 6,016 | ​ |

| ​ | ​ | $ | 1,943,037 | ​ | (38)% | ​ | $ | 3,151,181 | ​ |

During 2024, our steel operations achieved annual shipments of 12.7 million tons (11.4 million excluding intra-segment), slightly less than 2023 total record shipments.

Customer order activity and steel demand were stable during 2024, with the construction, automotive, industrial, and energy sectors leading demand.

In spite of strong market demand, average selling prices were lower during 2024 compared to 2023, as total steel segment average selling prices decreased 4%, or $46 per ton, compared to 2023.

| ​ | Inter-company | ​ | (3,656,034) | ​ | ​ | ​ | (3,593,328) | ​ |

| ​ | Inter-company | ​ | (171,915) | ​ | ​ | ​ | (207,866) | ​ |

Net sales for our metals recycling operations in 2024 were comparable to 2023 based on consistent shipments.

Due to a challenging pricing environment throughout much of 2024, ferrous average selling prices decreased 7% while nonferrous average selling prices increased 10% during 2024 compared to 2023.

As a result of the overall increased metals spreads, metals recycling operations operating income increased 61% to $76.8 million in 2024 compared to 2023.

Our steel fabrication operations benefited from a solid non-residential construction market, as evidenced by historically solid order backlog that extends deep into the first half of 2025 at attractive pricing levels.

The continued onshoring of manufacturing, coupled with the robust U.S. infrastructure and Inflation Reduction Act programs, supports consistent strong demand for steel joist and deck products.

The aluminum flat rolled products mill and the Mexico and US recycled aluminum slab centers are expected to begin operations in mid to late 2025.

Net sales relate to an entity with aluminum operations, previously reported as part of our metals recycling operations.

The results of this segment largely consist of construction and start-up costs recorded in selling, general, and administrative expenses, which continued to increase during 2024, consistent with increased headcount and start-up costs.

| Other Operations |

The lower interest expense in 2024 compared to 2023 is due to higher capitalized interest in 2024 ($66.8 million, compared to $33.0 million in 2023) related to our ongoing expansion projects, most notably within Aluminum Operations.

Our effective tax rate decrease was due primarily to certain discrete tax adjustments during the third quarter and fourth quarters of 2024.

It is reasonably possible that the amount of unrecognized tax benefits could change in the next twelve months in an amount ranging from zero to $12.0 million, as a result of the expiration of the statute of limitations and other federal and state income tax audits.

| ​ | ​ | ​ | Total liquidity | ​ | $ | 2,168,768 | ​ | ​ | ​ |

Our total outstanding debt of $3.2 billion increased $160.0 million compared to December 31, 2023, due to our issuance of $600.0 million of senior unsecured notes in July 2024 as described in Note 3, the proceeds of which were used for general corporate purposes, including the repayment of our 2.800% senior notes due December 2024, working capital, capital expenditures, advances for or investments in subsidiaries, acquisitions, redemption and repayment of other outstanding indebtedness, and purchases of the company’s common stock.

Working capital decreased $1.2 billion, or 26%, during 2024 to $3.3 billion at December 31, 2024, due primarily to a $1.4 billion decrease in cash and equivalents and short-term investments in support of our capital investments within our aluminum and steel operations.

We are currently executing our plan to invest $2.7 billion in a new state-of-the-art lower-carbon recycled aluminum flat rolled products mill with two new supporting satellite recycled aluminum slab centers, which are being funded by available cash and cash flow from operations.

Related expenditures began in the third quarter of 2022 and are expected to continue through 2025.

In February 2025, our board of directors authorized an additional share repurchase program of up to $1.5 billion of our common stock.

The following table represents the principal cash repayments and related weighted-average interest rates by maturity date for our long-term debt, as of December 31, [removed: 2024] [added: 2025] (in thousands):

At December 31, [removed: 2024,] [added: 2025,] we had a cumulative unrealized [removed: gain] [added: loss] associated with these financial contracts of [removed: $13.1] [added: $56.0] million, substantially all of which have settlement dates in [removed: 2025.][added: 2026.]

We believe [removed: the customer contracts associated with the financial] [added: these] contracts will be fully consummated.

| ​ | 2026 | ​ | $ | 1,493 | ​ | ​ | 5.2% | ​ | $ | 33,162 | ​ | ​ | 5.5% | ​ |

| ​ | 2027 | ​ | ​ | 351,099 | ​ | ​ | 1.7 | ​ | ​ | \- | ​ | ​ | ​ | ​ |

| ​ | 2028 | ​ | ​ | 650,416 | ​ | ​ | 4.0 | ​ | ​ | \- | ​ | ​ | ​ | ​ |

| ​ | 2029 | ​ | ​ | 198 | ​ | ​ | 5.1 | ​ | ​ | \- | ​ | ​ | ​ | ​ |

| ​ | 2030 | ​ | ​ | 600,095 | ​ | ​ | 3.5 | ​ | ​ | \- | ​ | ​ | ​ | ​ |

| ​ | Thereafter | ​ | ​ | 2,650,147 | ​ | ​ | 4.7 | ​ | ​ | \- | ​ | ​ | ​ | ​ |

| ​ | Total debt outstanding | ​ | $ | 4,253,448 | ​ | ​ | 4.2% | ​ | $ | 33,162 | ​ | ​ | 5.5% | ​ |

| ​ | Fair value | ​ | $ | 4,108,867 | ​ | ​ | ​ | ​ | $ | 33,162 | ​ | ​ | ​ | ​ |

| ​ | 2025 | ​ | $ | 401,071 | ​ | ​ | 2.4% | ​ | $ | 26,371 | ​ | ​ | 6.4% | ​ |

| ​ | 2026 | ​ | ​ | 400,896 | ​ | ​ | 5.0 | ​ | ​ | \- | ​ | ​ | ​ | ​ |

| ​ | 2027 | ​ | ​ | 350,465 | ​ | ​ | 1.7 | ​ | ​ | \- | ​ | ​ | ​ | ​ |

| ​ | 2028 | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | ​ | ​ |

| ​ | 2029 | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | ​ | ​ |

| ​ | Thereafter | ​ | ​ | 2,100,000 | ​ | ​ | 3.9 | ​ | ​ | \- | ​ | ​ | ​ | ​ |

| ​ | Total debt outstanding | ​ | $ | 3,252,432 | ​ | ​ | 3.6% | ​ | $ | 26,371 | ​ | ​ | 6.4% | ​ |

| ​ | Fair value | ​ | $ | 2,987,850 | ​ | ​ | ​ | ​ | $ | 26,371 | ​ | ​ | ​ | ​ |

Steel [removed: Dynamics, Inc.] [added: Dynamics] is one of the largest domestic steel producers and [removed: metal] [added: metals] recyclers in [removed: the United States,] [added: North America] based on estimated steelmaking and steel coating capacity of approximately 16 million tons and actual metals recycling volumes as of December 31, [removed: 2024,] [added: 2025,] with one of the most diversified product and end market portfolios in the domestic steel industry, combined with [added: a] meaningful downstream steel fabrication [removed: operations.][added: platform.]

The company [removed: is currently investing in its] [added: also has] aluminum [removed: operations to] [added: operations,] further [removed: diversify] [added: diversifying] its [removed: end markets with plans] [added: product offerings] to supply aluminum flat rolled products with [removed: high] [added: higher] recycled content to the [removed: countercyclical] [added: countercyclical,] sustainable beverage can industry, [removed: in addition to] [added: as well as] the automotive and industrial sectors.

[removed: Primary] [added: The company’s primary] sources of revenue are currently [added: derived] from the manufacture and sale of steel products, the processing and sale of recycled ferrous and nonferrous metals, and the fabrication and sale of steel [removed: joists] [added: joist] and deck products.

Our unique entrepreneurial culture and business model [removed: benefit us operationally, financially,] [added: create operational] and [removed: through] [added: financial advantages and support] the responsible use of [removed: our] resources [removed: in] [added: across] diverse economic environments.

Innovation in all forms is essential to our success, and our teams focus on [removed: how to do things “smarter”] [added: working smarter] within [removed: our current operations, as well as how we continue to grow.][added: existing operations while pursuing opportunities for continued growth.]

[removed: It also] [added: This] includes [added: developing solutions for our teammates, customers, suppliers, and other stakeholders, as well as] finding ways to [removed: “do business”] [added: operate] with fewer resources and less environmental impact.

[removed: Our] [added: The consistent execution of our] six strategic pillars [removed: and the team’s execution of them each day has driven] [added: drives] our [added: long-term] success and sustainability.

| | ● | Financial Strength – Through our adaptable value-added product diversification, vertically connected businesses model, [removed: coupled with our] highly variable operating cost structure and performance-based incentive compensation, along with our continued operating innovations and efficiency, we achieve higher utilization and lower costs, which provide strong cash flow generation through both strong and weak market cycles. |

Competitively advantaged differentiation [removed: in everything we do] is [removed: core] [added: central] to our long-term value creation strategy.

Our entrepreneurial culture is the foundation of our success and is driven by our extensive, performance-based incentive compensation philosophy [removed: for those] [added: that spans from teammates] on the plant floor to [removed: our] senior [removed: leadership team.][added: leadership.]

[removed: Over] [added: More than] 60% of a production team member’s total potential compensation is “at risk” [added: and tied] to [removed: both] quality production and cost-effectiveness metrics.

[removed: Over] [added: More than] 85% of our senior leadership team’s total potential compensation is “at risk” [added: and linked] to companywide financial [removed: performance] metrics that encourage long-term value creation, including return on equity, growth, cash generation, and return on invested [removed: capital measures.][added: capital.]

We have one of the most diversified, high-margin product [removed: offerings within] [added: portfolios in] the domestic steel [removed: industry.][added: industry and a proven track record of profitable growth.]

We have [removed: a track record of profitable growth, driving] [added: driven] diversification [removed: in] [added: across] both end markets and value-added product offerings to sustain higher [removed: volume] [added: volumes] and profitability through varying market environments.

[removed: Over] [added: Approximately] 70% of our steel and steel fabrication sales are considered value-added.

Throughout our history and today, we [removed: seek to provide unique] [added: have focused on providing differentiated] supply-chain [removed: alternatives for] [added: solutions that help] our customers [removed: to] increase efficiency, reduce time and costs, and [removed: promote] [added: support] decarbonization opportunities.

Growing [removed: with] [added: alongside] our customers in this [removed: manner] [added: way] has [removed: proven to be invaluable] [added: been instrumental] in [removed: creating] [added: building] long-lasting relationships and [added: advancing] product development.

The majority of our [removed: steelmaking] [added: scrap consuming] operations are [removed: in locations] [added: located] near sustainable sources of scrap [removed: metals] [added: metal] and [removed: near] [added: close to] our customer base, [removed: allowing us to realize] [added: creating] freight savings [removed: for] [added: on] inbound scrap [removed: as well as for] [added: and] outbound [removed: steel products destined for our customers.][added: finished products.]

This [added: proximity] also allows us to provide [removed: consistent] [added: consistent,] on-time delivery [removed: to our customer base] with relatively short lead times, further [removed: solidifying] [added: strengthening] our customer relationships.

This diversified [added: product] portfolio [removed: of products] enables us to access a broad range of [removed: markets,] [added: markets and] serve a large customer base, [removed: and helps] [added: while helping to] mitigate [removed: our market] exposure to any [removed: one] [added: single] product or [removed: sector, resulting in increased] [added: end market and supporting higher] through-cycle [removed: steel] mill utilization.

[removed: In addition, our] [added: Our] value-added product offerings [added: also] help [removed: to] balance our exposure to commodity grade products supplied by other manufacturers.

We will continue to seek additional opportunities, [removed: such as entering] [added: including our entry into] the recycled aluminum flat rolled products market, and collaborating with our customers to anticipate their future needs by further expanding our range of products and offerings.

As with all [added: of] our growth initiatives, we seek to competitively differentiate ourselves through service, product capability and quality, and [added: integrated] supply-chain solutions.

Our vertically connected businesses [removed: contribute to] [added: support] our higher through-cycle steel production and overall profitability.

Our internal manufacturing [removed: businesses are] [added: operations provide] a significant competitive advantage [removed: supporting higher and] [added: by contributing to] more stable through-cycle earnings and cash flow generation.

Our steel fabrication operations and downstream processing [removed: locations use a] [added: facilities consume] significant [removed: amount] [added: volumes] of [removed: steel in their operations.][added: steel.]

During weaker steel demand environments, we can source their steel needs internally, and during [removed: strong] [added: stronger] steel demand environments, we [removed: have the option to] [added: may] also purchase [removed: their] steel [removed: needs] externally.

In [removed: 2024,] [added: 2025,] our own steel consuming businesses purchased [removed: 1.7] [added: 1.8] million tons of steel from our steel mills, representing [removed: 14%] [added: 13%] of our total [removed: 2024] [added: 2025] steel shipments.

A strategic and synergistic relationship [removed: also] exists between our electric arc furnace (EAF) steel mills and [added: our] metals recycling [added: operations, as well as between our aluminum operations and our metals recycling] operations.

Our metals recycling platform is the largest supplier of recycled ferrous scrap to our steel operations and [removed: is expected to be] the largest supplier of recycled aluminum scrap to our aluminum operations.

This [added: circular model] allows us to reduce companywide working capital, as lower scrap inventory volume is required at our steel [removed: mills.][added: mills and aluminum operations.]

We are also able to source higher-quality scrap for our steel [removed: mills,] [added: mills and aluminum operations,] increasing availability, optimizing costs, and improving quality.

We [removed: operate] [added: have] some of the most technologically advanced and environmentally responsible steel mills [added: and aluminum operations] in the world.

Coupled with our low, highly variable cost structure and our continued operating innovation and efficiency, we are one of the most profitable and lowest-cost domestic [removed: steel producers.][added: metals solutions companies.]

Our [removed: investment includes] [added: aluminum operations consist of] a [removed: 650,000-metric ton] [added: 650,000-metric-ton] recycled aluminum flat rolled products mill in Columbus, [removed: Mississippi, and] [added: Mississippi;] two [removed: supporting] [added: 150,000-metric-ton] satellite recycled aluminum slab [removed: centers.][added: centers, one in Central Mexico and one under construction in the Southwest U.S.; and an ancillary recycled aluminum deox-rod facility.]

[removed: A] [added: Customers and Markets. We have intentionally aligned the growth of our aluminum operations to serve a] significant number of our existing carbon flat [removed: rolled] [added: roll] steel customers [added: who] also consume, or [removed: process] [added: process,] aluminum flat rolled products for automotive, appliance, construction, and other applications.

[removed: We are developing our property to] allow customers to [removed: locate] [added: co-locate] on-site, with one customer already [removed: committed to co-locating] [added: in the construction process] and others expected to co-locate at the rolling mill site in Columbus, enhancing cost efficiencies and reducing emissions across the supply chain.

[removed: The product mix from] [added: Once] the [added: recycled aluminum] flat rolled products mill [removed: is expected to be] [added: reaches full production, we anticipate our aluminum operations product mix will consist of] approximately 45% [removed: sustainable beverage packaging,] [added: can sheet,] 35% automotive, and 20% common alloy and industrial [removed: use.][added: applications.]

The [removed: state-of-the-art recycled aluminum] flat rolled products mill [removed: will utilize a significant amount of] [added: produces flat rolled] aluminum [removed: scrap,] [added: coil products from aluminum scrap] and [removed: as such] is [removed: also] a complementary extension of [removed: the company’s] [added: our] metals recycling platform.

[removed: The] [added: Our] product [removed: offering] [added: offerings] will be supported by various value-added finishing [removed: lines,] [added: lines that are being commissioned,] including two CASH [removed: (continuous annealing solutions heat treating)] [added: (Continuous Annealing Solutions Heat Treating)] lines, a [added: can end and tab] coating line, and downstream processing and packaging lines.

Steel Dynamics, Inc. is a leading industrial metals solutions company, with facilities located throughout the United States and Mexico.

The company operates a circular manufacturing model, producing high-quality, lower-carbon-emission products with recycled scrap as the primary input.

These pillars unify our teams around a common focus and provide the foundation for how we operate and grow.

We distinguish ourselves across all aspects of our business through an overarching culture of excellence that drives how we operate, innovate, and serve our customers.

Our new recycled aluminum flat rolled products mill uses recycled aluminum scrap as its primary raw material and is engineered to provide an energy-efficient, lower-environmental-impact product alternative compared to average aluminum flat rolled production.

These investments allow us to produce high-quality, lower-embodied-carbon steel and aluminum products for our customers and drive returns for our shareholders.

| Matt Bell | ​ | 49 | ​ | Vice President, Metals Recycling |

In 2025, Mr. Millett received Harbor Aluminum’s Gene Greenberg 2025 World’s Aluminum Executive of the Year Award, an award that honors leaders with integrity who have made significant contributions to technically improve and/or disrupt the aluminum industry for the better.

Also in 2025, Mr. Millett was the recipient of the Bessemer Gold Medal, a Premier Award from the Institute of Materials, Minerals & Mining, honoring those who have contributed significantly to the steel industry.

_Miguel Alvarez_ was appointed Senior Vice President, Aluminum Group in October 2025.

Mr. Alvarez is responsible for new strategic aluminum investments, as well as an ancillary recycled aluminum deox-rod facility.

Beginning in

March 2022, Mr. Alvarez served as Senior Vice President, Metals Recycling and was responsible for leading Omni’s ferrous and nonferrous metals recycling operations, including marketing, trading, and logistics activities.

_Matt Bell_ was appointed Vice President, Metals Recycling in November 2025.

Beginning in 2023, Mr. Bell served as Vice President of Commercial for Omni, responsible for developing and implementing its ferrous purchasing and sales growth strategies, including optimizing the scrap supply for the company’s steel operations.

Since joining the company in 2016, Mr. Bell has held increasingly impactful leadership roles within the metals recycling platform in operations, commercial, and marketing responsibilities, including Southwest Commercial Manager from 2020 to 2022 and Ferrous Trading Manager until 2023.

Prior to joining the company, he held various leadership positions in the metals recycling industry.

Matt is an alumnus of the Executive Education Program at the University of Texas McCombs School of Business as well as the Emerging Leaders Program at Northwestern University’s Kellogg School of Management.

*​*

manufacturing facilities located throughout the United States and Mexico.

We believe trust is reinforced through effective communication and transparency, and we are confident our teams will do what is right.

Our leadership team is engaged and continuously evaluates opportunities for improvement.

Our culture is built on safeguarding all individuals and ensures everyone is treated fairly, with dignity and respect.

Through United Steel Supply (“USS”) and New Process Steel, L.P. (“NPS”) (acquired December 1, 2025), we also have distribution and processing of metallic coated and pre-painted products.

Distribution and steel processing is provided through USS and NPS.

The following chart summarizes sheet steel product sales by product type, based on sales dollars, during the respective years.

Cold rolled and coated products are considered value-added products:

USS and NPS provide complementary distribution channels for metallic-coated and pre-painted flat rolled steel coils and steel processing capabilities, including slitting, blanking, cutting to length, stamping and fabrication services.

USS primarily serves roll-former customers in the roofing and siding industry, while also expanding our reach to customers that have not historically purchased steel directly from a primary steel producer.

NPS serves a wide range of customers, including those in agriculture, appliance, automotive, and construction industries, as well as other markets.

| ​ | ​ | 2025 | ​ | 2024 | ​ | 2023 | ​ | ​ |

| |

| Aluminum Operations Segment |

The results of our aluminum operations for 2025, 2024, and 2023 largely consisted of sales from the ancillary recycled aluminum deox-rod facility, as well as construction, start-up, and commissioning costs associated with the recycled aluminum flat rolled products mill and satellite recycled aluminum slab centers.

During the second half of 2025, the recycled aluminum flat rolled products mill produced finished products for the industrial and beverage can markets and achieved product certifications across multiple customers.

In addition, the mill also successfully produced and qualified aluminum hot rolled coils for automotive applications.

Aluminum operations accounted for 2% of our consolidated net sales in 2025, and 1%, in each of 2024 and 2023.

Products. Our aluminum operations provide flat rolled products with high recycled content to the countercyclical, sustainable beverage can industry, as well as the automotive and industrial sectors.

We are further diversifying our end markets by supplying aluminum flat rolled products to the sustainable beverage can industry.

We have developed our real estate to

They bring us together with a common focus, and they provide the foundation upon which we operate and grow.

This means creating solutions for our teammates, customers, suppliers, and other stakeholders.

We distinguish ourselves in every aspect of our business through an overarching spirit of excellence.

In 2024, we began operations on our four new value-added flat roll steel coating lines comprised of an additional paint line and galvanizing line located onsite at our Southwest-Sinton Flat Roll Division and a paint line and galvanizing line at our Heartland Flat Roll Division.

Transformational Growth / New Recycled Aluminum Flat Rolled Strategic Investments

We are nearing the completion of our lower-carbon-emitting, recycled aluminum flat rolled products mill.

We are bringing our culture and related operating efficiencies to the flat rolled aluminum industry.

This investment will allow us to broaden our ability to serve our existing customers as well as new customers by adding high-quality, lower-carbon flat rolled aluminum to our product portfolio.

We plan to begin shipments mid-year 2025.

Our unique performance-based operating culture, coupled with our experience in successfully constructing and operating cost-effective, highly profitable flat roll steel mills and coating lines, positions us exceptionally well to execute this significant strategic investment.

In 2023, we began construction of a biocarbon production facility located in Columbus, Mississippi.

| Glenn A. Pushis | ​ | 59 | ​ | Senior Vice President, Special Projects |

Before that, Mr. Schneider served in various

_Miguel Alvarez_ has been our Senior Vice President, Metals Recycling since March 2022.

Poinsatte_ has been our Senior Vice President and Treasurer since October 2023.

_Glenn A.

Pushis_ has been our Senior Vice President, Special Projects, since February 2019.

Mr. Pushis is responsible for the successful design and construction of the company’s new 650,000-metric ton state-of-the-art lower-carbon, recycled aluminum flat rolled products mill in Columbus, Mississippi with two satellite recycled aluminum slab centers in the Southwestern United States and San Luis Potosi, Mexico.

From 2019 until 2022, Mr. Pushis was responsible for the successful design and construction of the Company’s new Southwest-Sinton Flat Roll Division, developed to serve the Southwestern United States and Mexico.

He has extensive experience in this capacity and has

been instrumental in numerous construction projects for Steel Dynamics since its founding.

Prior to that, Mr. Pushis served as Senior Vice President, Long Products Steel Group, responsible for the company’s four long product steel mills.

He was also a part of the team that constructed the company’s first steel mill in Butler, Indiana, in 1994.

Mr. Pushis earned a bachelor’s degree in mechanical engineering from Purdue University and his MBA from Indiana University.

In addition, Mr. Pushis served as a Past President of the Association for Iron & Steel Technology Foundation.

Mr. Bickford has been with Steel Dynamics since 2003, holding various operational and leadership roles with increasing responsibility in both steel and steel fabrication operations, including General Manager for the company’s Engineered Bar Products Division and General Manager of the Virginia steel fabrication facility.

We know our teams will do what is right and that trust comes from effective communication and transparency.

This is achievable when we all work together.

Leadership is engaged and continuously evaluates where we can improve.

We believe having every individual engaged in safety will lead to zero injuries.

Our people represent the foundation of our six strategic pillars.

Our culture safeguards all people and requires each person to be treated fairly and with dignity.

In the fourth quarter 2024, results from an entity previously reported within the metals recycling operations were moved to the aluminum operations segment, consistent with how the company’s chief operating decision maker currently manages the business.

Segment information provided within this Form 10-K has been recast for all prior periods presented, consistent with the current reportable segment presentation.

These capacities do not represent expected volumes in a given year.

The following chart summarizes the types of sheet steel products sold by sales dollars, during the respective years, with cold rolled and coated products representing value-added products:

USS adds a complementary distribution channel for metallic coated and pre-painted flat roll steel coils to the roll-former market, serving the roofing and siding industry.

This connects us to an industry sector with customers that have not historically purchased steel directly from a steel producer.

Our Structural and Rail Division purchases electricity at current market prices and through fixed price forward contracts.

Some of these matters have resulted in fines or penalties, exclusive of interest and costs, which did not exceed $1 million in aggregate, as of December 31, [removed: 2024.][added: 2025.]

| ☒ | ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31, [removed: 2024] [added: 2025] |

| Indiana | [added: ​ ​ ​] | 35-1929476 |

The aggregate market value of the voting stock held by non-affiliates of the registrant computed by reference to the price at which the common equity was last sold as of June 30, [removed: 2024,] [added: 2025,] was approximately [removed: $14.8] [added: $13.0] billion.

As of February [removed: 24, 2025,] [added: 25, 2026,] Registrant had outstanding [removed: 150,163,986] [added: 144,882,401] shares of common stock.

Portions of registrant’s definitive proxy statement for the [removed: 2025] [added: 2026] Annual Meeting of Shareholders are incorporated by reference into Part III, Items 10 through 14, of this report.

| [Item 1B.](#ITEM1BUNRESOLVEDSTAFFCOMMENTS_407146) | [Unresolved Staff Comments](#ITEM1BUNRESOLVEDSTAFFCOMMENTS_407146) | [removed: 30] [added: 31] |

| [Item 6.](#ITEM6) | [\[Reserved\]](#ITEM6) | [removed: 37] [added: 36] |

| [Item 7.](#ITEM7MANAGEMENTSDISCUSSIONANDANALYSISOFF) | [Management’s Discussion and Analysis of Financial Condition and Results of Operations](#ITEM7MANAGEMENTSDISCUSSIONANDANALYSISOFF) | [removed: 38] [added: 37] |

| [Item 7A.](#ITEM7AQUANTITATIVEANDQUALITATIVEDISCLOSU) | [Quantitative and Qualitative Disclosures About Market Risk](#ITEM7AQUANTITATIVEANDQUALITATIVEDISCLOSU) | [removed: 50] [added: 49] |

| [Item 8.](#ITEM8CONSOLIDATEDFINANCIALSTATEMENTS_437) | [Consolidated Financial Statements and Supplementary Data](#ITEM8CONSOLIDATEDFINANCIALSTATEMENTS_437) | [removed: 51] [added: 50] |

| [Item 9.](#ITEM9CHANGESINANDDISAGREEMENTSWITHACCOUN) | [Changes in and Disagreements with Accountants on Accounting and Financial Disclosure](#ITEM9CHANGESINANDDISAGREEMENTSWITHACCOUN) | [removed: 82] [added: 83] |

| [Item 9A.](#Item9A) | [Controls and Procedures](#Item9A) | [removed: 82] [added: 83] |

| [Item 9B.](#ITEM9BOTHERINFORMATION_500127) | [Other Information](#ITEM9BOTHERINFORMATION_500127) | [removed: 82] [added: 83] |

| [Item 9C.](#ITEM9C) | [Disclosure Regarding Foreign Jurisdictions that Prevent Inspections](#ITEM9C) | [removed: 82] [added: 83] |

| [Item 10.](#ITEM10DIRECTORSEXECUTIVEOFFICERS_95546) | [Directors, Executive Officers, and Corporate Governance](#ITEM10DIRECTORSEXECUTIVEOFFICERS_95546) | [removed: 83] [added: 84] |

| [Item 11.](#ITEM11EXECUTIVECOMPENSATION_392678) | [Executive Compensation](#ITEM11EXECUTIVECOMPENSATION_392678) | [removed: 83] [added: 84] |

| [Item 12.](#ITEM12SECURITYOWNERSHIPOFCERTAINBENEFICI) | [Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters](#ITEM12SECURITYOWNERSHIPOFCERTAINBENEFICI) | [removed: 83] [added: 84] |

| [Item 13.](#ITEM13CERTAINRELATIONSHIPSANDRELATEDTRAN) | [Certain Relationships and Related Transactions, and Director Independence](#ITEM13CERTAINRELATIONSHIPSANDRELATEDTRAN) | [removed: 84] [added: 85] |

| [Item 14.](#ITEM14PRINCIPALACCOUNTANTFEESANDSERVICES) | [Principal Accountant Fees and Services](#ITEM14PRINCIPALACCOUNTANTFEESANDSERVICES) | [removed: 84] [added: 85] |

| [Item 15.](#ITEM15EXHIBITSFINANCIALSTATEMENTSCHEDULE) | [Exhibits and Financial Statement Schedules](#ITEM15EXHIBITSFINANCIALSTATEMENTSCHEDULE) | [removed: 85] [added: 86] |

| [Item 16.](#ITEM16FORM10KSUMMARY_712404) | [Form 10-K Summary](#ITEM16FORM10KSUMMARY_712404) | [removed: 85] [added: 86] |

| [Exhibit Index](#EXHIBITINDEX_376119) | | [removed: 86] [added: 87] |

| [Signatures](#SIGNATURES_483178) | | [removed: 89] [added: 90] |

| | ● | the cyclical nature of the [removed: steel industry] [added: metals industries] and some of the industries we serve; |

| | ● | our [removed: senior unsecured credit facility contains,] [added: existing debt agreements contain,] and any future financing agreements may contain, restrictive covenants that may limit our flexibility; and |

| | ● | difficulties in the launch or production ramp-up of new products; |

| | ● | our aluminum operations depend on a core group of significant customers; |

| --- | --- | --- |

| | ● | pandemics, epidemics, widespread illness or other health issues; |

Our policies, procedures, and processes [removed: follow] [added: utilize] recognized frameworks established by the National Institute of Standards and Technology (“NIST”), as well as other relevant standards.

Our [removed: Director of] Information Security [removed: is responsible for leading the Information Security] Team [removed: which] has established a cybersecurity risk management program of policies and processes for assessing, identifying, and managing risk from cybersecurity threats.

The information security training and awareness program engages personnel through training modules on how to identify potential cybersecurity risks and protect [removed: the Company’s] [added: our] resources and information.

In general, our incident response process [removed: follows] [added: utilizes] the NIST framework and focuses on four phases: (i) preparation; (ii) detection and analysis; (iii) containment, eradication, and recovery; and (iv) post-incident remediation.

As cybersecurity incidents occur, including at third party providers, the [removed: Director of] Information Security [removed: leads the Information Security] Team [removed: through] [added: engages in] a standardized incident response process that focuses on responding to and containing the threat, minimizing any business impact, and evaluating its severity level.

On a quarterly basis, the Audit Committee is informed by management concerning the status of existing and new cybersecurity risks, status of how management is addressing and mitigating those risks, [added: material] cybersecurity and data privacy incidents (if any), and status of key information security initiatives.

The ISG is an [removed: internal] [added: internal, collaborative] working group that [removed: collaborates with the Director of Information Security to ensure] [added: ensures] our cybersecurity program is adequately responsive to the evolving threat landscape.

This group contains members with a master’s degree in information security, as well as individuals with over 20 years of experience in cybersecurity.

Our Director of Information Security has over twenty years of cybersecurity experience, has completed a Masters in Homeland Security, with an emphasis on cybersecurity, and holds several cybersecurity certifications.

The following table describes our significant properties as of December 31, [removed: 2024.][added: 2025.]

| Butler Operations | ​ | Butler, IN | ​ | Flat Roll Steel Mill and Coating Facility | ​ | [removed: 993] [added: 995] | ​ | — |

| The Techs | ​ | Pittsburgh, PA | ​ | Flat Roll Steel Coating Facilities | ​ | [removed: 16] [added: 17] | ​ | 2 |

| Steel of West Virginia | ​ | WV, KY, and TN | ​ | Specialty Shapes Steel Mill and Finishing | ​ | [removed: 139] [added: 141] | ​ | 6 |

| Texas | ​ | Multiple Cities | ​ | Ferrous and Nonferrous Scrap Processing | ​ | 130 | ​ | [removed: 12] [added: 9] |

| Superior Aluminum Alloys | ​ | New Haven, IN | ​ | [added: Recycled] Aluminum [removed: Operations] [added: Deox-Rod Facility] | ​ | 96 | ​ | — |

The company’s corporate headquarters is [added: located] in Fort Wayne, Indiana on 20 owned acres.

*Our [removed: 2024] [added: 2025] steel mill production utilization was [removed: 81%] [added: 86%] of our estimated annual steelmaking capability.

| New Process Steel | ​ | IN, IL, MS, AL, TX, and Monterrey, Mexico | ​ | Flat Roll Steel Distributor and Processing Facility | ​ | — | ​ | 23 |

As of February [removed: 24, 2025,] [added: 25, 2026,] we had [removed: 150,163,986] [added: 144,882,401] shares of common stock outstanding and held beneficially by approximately [removed: 30,000] [added: 25,000] stockholders based on our security position listing.

Because many of the shares were held by depositories, brokers and other nominees, the number of registered holders (approximately [removed: 1,220)] [added: 1,160)] is not representative of the number of beneficial holders.

We purchased the following equity securities registered by us pursuant to Section 12 of the Exchange Act during the three months ended December 31, [removed: 2024.][added: 2025.]

| Quarter ended December 31, [removed: 2024] [added: 2025] | | | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ |

| (1) | In [removed: November 2023, our board of directors authorized a share repurchase program of up to $1.5 billion of our common stock. In] February 2025, our board of directors authorized [removed: an additional] [added: a] share repurchase program of up to $1.5 billion of our common stock. |

The graph tracks the performance of a $100 investment in our common stock and in each index (with the reinvestment of all dividends) from December 31, [removed: 2019] [added: 2020] to December 31, [removed: 2024.][added: 2025.]

[removed: ][added: ]

| October 1-31 | ​ | 109,815 | ​ | $ | 146.90 | ​ | ​ | 109,815 | ​ | $ | 1,023,609 |

| November 1-30 | ​ | 910,321 | ​ | ​ | 157.62 | ​ | ​ | 910,321 | ​ | ​ | 881,551 |

| December 1-31 | ​ | 466,035 | ​ | ​ | 173.11 | ​ | ​ | 466,035 | ​ | ​ | 800,968 |

| ​ | ​ | 1,486,171 | ​ | ​ | ​ | ​ | ​ | 1,486,171 | ​ | ​ | ​ |

| October 1-31 | ​ | 664,066 | ​ | $ | 132.25 | ​ | ​ | 664,066 | ​ | $ | 399,476 |

| November 1-30 | ​ | 790,538 | ​ | ​ | 144.37 | ​ | ​ | 790,538 | ​ | ​ | 286,494 |

| December 1-31 | ​ | 728,796 | ​ | ​ | 128.87 | ​ | ​ | 728,796 | ​ | ​ | 193,510 |

| ​ | ​ | 2,183,400 | ​ | ​ | ​ | ​ | ​ | 2,183,400 | ​ | ​ | ​ |

| ​ | [added: ​ ​ ​] | Page |

| [Management’s Report on Internal Control Over Financial Reporting](#MANAGEMENTSREPORTONINTERNALCONTROL_58491) | ​ | [removed: 52] [added: 51] |

| [Reports of Independent Registered Public Accounting Firm](#REPORTOFINDEPENDENTREGISTEREDPUBLICACCOU) (PCAOB ID 42) | ​ | [removed: 53] [added: 52] |

| [Consolidated Balance Sheets as of December 31, [removed: 2024] [added: 2025] and [removed: 2023](#CONSOLIDATEDBALANCESHEETS_923745)] [added: 2024](#CONSOLIDATEDBALANCESHEETS_923745)] | ​ | 56 |

| [Consolidated Statements of Income for each of the three years in the period ended December 31, [removed: 2024](#CONSOLIDATEDSTATEMENTSOFINCOME_871598)] [added: 2025](#CONSOLIDATEDSTATEMENTSOFINCOME_871598)] | ​ | 57 |

| [Consolidated Statements of Comprehensive Income for each of the three years in the period ended December 31, [removed: 2024](#COMPREHENSIVEINCOME_913078)] [added: 2025](#COMPREHENSIVEINCOME_913078)] | ​ | 58 |

| [Consolidated Statements of Equity for each of the three years in the period ended December 31, [removed: 2024](#CONSOLIDATEDSTATEMENTSOFEQUITY_192323)] [added: 2025](#CONSOLIDATEDSTATEMENTSOFEQUITY_192323)] | ​ | 59 |

| [Consolidated Statements of Cash Flows for each of the three years in the period ended December 31, [removed: 2024](#CONSOLIDATEDSTATEMENTSOFCASHFLOWS_963353)] [added: 2025](#CONSOLIDATEDSTATEMENTSOFCASHFLOWS_963353)] | ​ | 60 |

Based on that evaluation, management concluded that our internal control over financial reporting was effective as of December 31, [removed: 2024,] [added: 2025,] the end of the period covered by this report.

| /s/ Mark D. Millett | [added: ​ ​ ​] | /s/ Theresa E. Wagler |

We have audited Steel Dynamics, Inc.’s internal control over financial reporting as of December 31, [removed: 2024,] [added: 2025,] based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework) (the COSO criteria).

In our opinion, Steel Dynamics, Inc. (the Company) maintained, in all material respects, effective internal control over financial reporting as of December 31, [removed: 2024,] [added: 2025,] based on the COSO criteria.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, [removed: 2024] [added: 2025] and [removed: 2023,] [added: 2024,] the related consolidated statements of income, comprehensive income, equity, and cash flows for each of the three years in the period ended December 31, [removed: 2024,] [added: 2025,] and the related notes and our report dated February [removed: 28, 2025] [added: 27, 2026] expressed an unqualified opinion thereon.

We have audited the accompanying consolidated balance sheets of Steel Dynamics, Inc. (the Company) as of December 31, [removed: 2024] [added: 2025] and [removed: 2023,] [added: 2024,] the related consolidated statements of income, comprehensive income, equity and cash flows for each of the three years in the period ended December 31, [removed: 2024,] [added: 2025,] and the related notes (collectively referred to as the “consolidated financial statements”).

In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at December 31, [removed: 2024] [added: 2025] and [removed: 2023,] [added: 2024,] and the results of its operations and its cash flows for each of the three years in the period ended December 31, [removed: 2024,] [added: 2025,] in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, [removed: 2024,] [added: 2025,] based on criteria established in Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework), and our report dated February [removed: 28, 2025] [added: 27, 2026] expressed an unqualified opinion thereon.

Critical Audit [removed: Matter][added: Matters]

The critical audit [removed: matter] [added: matters] communicated below [removed: is a matter] [added: are matters] arising from the current period audit of the financial statements that [removed: was] [added: were] communicated or required to be communicated to the audit committee and that: (1) [removed: relates] [added: relate] to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments.

The communication of the critical audit [removed: matter] [added: matters] does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit [removed: matter] [added: matters] below, providing a separate opinion on the critical audit [removed: matter] [added: matters] or on the account or disclosure to which it relates.

| _Description of__the Matter_ | At December 31, [removed: 2024,] [added: 2025,] the Company’s goodwill was approximately $477 million. As discussed in Note 1 of the consolidated financial statements, the Company performs an impairment test for goodwill at least annually or when indicators of impairment exist. The Company performed a qualitative assessment as of October 1, [removed: 2024,] [added: 2025,] to assess if it is more likely than not that the fair value of a reporting unit exceeds its carrying amount. | |

| Assets | [removed: 2024] [added: 2025] | | ​ | ​ | [removed: 2023] [added: 2024] | |

| Cash and equivalents | $ | [removed: 589,464] [added: 769,878] | ​ | ​ | $ | [removed: 1,400,887] [added: 589,464] |

| Short-term investments | ​ | [removed: 147,811] [added: \-] | ​ | ​ | ​ | [removed: 721,210] [added: 147,811] |

| Accounts receivable, net of allowances for credit losses of [removed: $7,728] [added: $5,419] and [removed: $8,480] [added: $7,728] | ​ | ​ | ​ | ​ | ​ | ​ |

| as of December 31, [removed: 2024] [added: 2025] and [removed: 2023,] [added: 2024,] respectively | ​ | [removed: 1,362,969] [added: 1,680,249] | ​ | ​ | ​ | [removed: 1,535,062] [added: 1,362,969] |

| Accounts receivable-related parties | ​ | [removed: 54,230] [added: 2,411] | ​ | ​ | ​ | [removed: 73,245] [added: 54,230] |

| Inventories | ​ | [removed: 3,113,733] [added: 3,738,516] | ​ | ​ | ​ | [removed: 2,894,632] [added: 3,113,733] |

| Other current assets | ​ | [removed: 163,131] [added: 293,117] | ​ | ​ | ​ | [removed: 162,790] [added: 163,131] |

| Total current assets | ​ | [removed: 5,431,338] [added: 6,484,171] | ​ | ​ | ​ | [removed: 6,787,826] [added: 5,431,338] |

| Property, plant and equipment, net | ​ | [removed: 8,117,988] [added: 8,569,466] | ​ | ​ | ​ | [removed: 6,734,218] [added: 8,117,988] |

| Intangible assets, net | ​ | [removed: 227,234] [added: 331,290] | ​ | ​ | ​ | [removed: 257,759] [added: 227,234] |

| Other assets | ​ | [removed: 681,202] [added: 557,382] | ​ | ​ | ​ | [removed: 651,146] [added: 681,202] |

| Total assets | $ | [removed: 14,935,233] [added: 16,419,780] | ​ | ​ | $ | [removed: 14,908,420] [added: 14,935,233] |

| Accounts payable | $ | [removed: 972,645] [added: 1,223,776] | ​ | ​ | $ | [removed: 1,078,645] [added: 972,645] |

| Accounts payable-related parties | ​ | [removed: 7,267] [added: 7,582] | ​ | ​ | ​ | [removed: 9,685] [added: 7,267] |

| Income taxes payable | ​ | [removed: 3,783] [added: 67,315] | ​ | ​ | ​ | [removed: 5,524] [added: 3,783] |

| Accrued payroll and benefits | ​ | [removed: 373,216] [added: 361,494] | ​ | ​ | ​ | [removed: 469,143] [added: 373,216] |

| Accrued expenses | ​ | [removed: 366,682] [added: 427,432] | ​ | ​ | ​ | [removed: 309,312] [added: 366,682] |

| Current maturities of long-term debt | ​ | [removed: 426,990] [added: 34,655] | ​ | ​ | ​ | [removed: 459,987] [added: 426,990] |

| Total current liabilities | ​ | [removed: 2,150,583] [added: 2,122,254] | ​ | ​ | ​ | [removed: 2,332,296] [added: 2,150,583] |

We completed the acquisition of the remaining 55% interest in New Process Steel, L.P. (NPS) on December 1, 2025.

In conducting our evaluation of the effectiveness of our internal control over financial reporting as of December 31, 2025, we have elected to exclude NPS from our evaluation in the year of acquisition as permitted by the Securities and Exchange Commission.

NPS constituted approximately 3% and 5% of the company’s total and net assets, respectively, as of December 31, 2025, and 0.4% of the company’s net sales for the year then ended.

As indicated in the accompanying Management's Report on Internal Control Over Financial Reporting, management's assessment of and conclusion on the effectiveness of internal control over financial reporting did not include the internal controls of New Process Steel, L.P., which is included in the 2025 consolidated financial statements of the Company and constituted 3% and 5% of total and net assets, respectively, as of December 31, 2025, and 0.4% of net sales, for the year then ended.

Our audit of internal control over financial reporting of the Company also did not include an evaluation of the internal control over financial reporting of New Process Steel, L.P.

February 27, 2026

| ​ | Valuation of Acquired Customer Relationships Intangible Asset | |

| _Description of__the Matter_ | As described in Note 2 to the consolidated financial statements, on December 1, 2025, the Company completed the acquisition of the remaining 55% interest in New Process Steel, L.P. for a purchase price of $229 million. The Company measured the assets and liabilities assumed at fair value, which resulted in the recognition of a customer relationships intangible asset of $96 million. | |

| ​ | Auditing the valuation of the acquired customer relationships intangible asset required auditor judgment due to the nature and extent of audit effort in evaluating certain assumptions required to estimate the fair value using a multi-period excess earnings method, which is a specific discounted cash flow method. In particular, the fair value measurement of customer relationships utilized management’s forecasts of revenue growth rates and projected margins to estimate the discounted cash flows. | |

| _How We__Addressed the__Matter in Our__Audit_ | We obtained an understanding, evaluated the design and tested the operating effectiveness of controls over the Company’s process to estimate the fair value of the acquired customer relationships intangible asset, including controls over management’s review of the significant assumption described above. | |

| ​ | To test the fair value estimate of the customer relationships intangible asset, we performed audit procedures which included, among others, testing the significant assumptions described above, testing the completeness and accuracy of the underlying data, and evaluating the valuation methodology with the assistance of our valuation specialists. We compared the significant assumptions to current industry and economic trends and historical results of the acquired business. We performed sensitivity analyses to evaluate the impact of changes in the significant assumptions to the fair value of the customer relationships intangible asset. | |

February 27, 2026

| Dividends declared | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | (294,132) | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | (294,132) | ​ | ​ | \- |

| Noncontrolling investors, net | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | (9,460) | ​ | ​ | (9,460) | ​ | ​ | (29,986) |

| Share repurchases | ​ | (6,680) | ​ | ​ | 6,680 | ​ | ​ | \- | ​ | ​ | (900,870) | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | (900,870) | ​ | ​ | \- |

| Equity-based compensation | ​ | 503 | ​ | ​ | (236) | ​ | ​ | 1 | ​ | ​ | 14,587 | ​ | ​ | 18,815 | ​ | ​ | (503) | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | 32,900 | ​ | ​ | \- |

| Net income | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | 1,185,595 | ​ | ​ | \- | ​ | ​ | 1,716 | ​ | ​ | 1,187,311 | ​ | ​ | \- |

| Balances at December 31, 2025 | ​ | 144,940 | ​ | ​ | 123,704 | ​ | $ | 653 | ​ | $ | (7,980,549) | ​ | $ | 1,248,634 | ​ | $ | 15,689,042 | ​ | $ | (598) | ​ | $ | (167,997) | ​ | $ | 8,789,185 | ​ | $ | 141,226 |

Steel Dynamics, Inc. (SDI), together with its subsidiaries (the company), is a leading industrial metals solutions company, with facilities located throughout the United States and Mexico.

The company also has aluminum operations, further diversifying its product offerings to supply aluminum flat rolled products with higher recycled content to the countercyclical, sustainable beverage can industry, as well as the automotive and industrial sectors.

There were no short-term investments held as of December 31, 2025.

| ​ | ​ | 2025 | | ​ | 2024 | | ​ |

| s | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ |

| ​ | ​ | ​ | 2025 | | ​ | 2024 | | ​ |

| ​ | ​ | ​ | ​ | 13,617,531 | ​ | ​ | 12,722,478 | ​ |

| ​ | 2026 | ​ | $ | 30,840 | ​ |

| ​ | 2027 | ​ | ​ | 28,441 | ​ |

| ​ | 2030 | ​ | ​ | 23,168 | ​ |

| ​ | Thereafter | ​ | ​ | 196,749 | ​ |

| ​ | Total | ​ | $ | 331,290 | ​ |

discount rates), industry and market conditions, recent and projected financial performance, the company’s competitive position and other factors.

When conducting a quantitative test, the fair value of the reporting unit is determined by

There were 62,000 anti-dilutive common share equivalents for the three-month period ended March 31, 2025 excluded from common share equivalents for the year ended December 31, 2025.

| ​ | ​ | 2025 | | | | | | | | ​ | ​ | 2024 | | | | | | | |

| Basic earnings per share | ​ | $ | 1,185,595 | ​ | ​ | 147,806 | ​ | $ | 8.02 | ​ | ​ | $ | 1,537,134 | ​ | ​ | 155,420 | ​ | $ | 9.89 |

| Diluted earnings per share | ​ | $ | 1,185,595 | ​ | ​ | 148,404 | ​ | $ | 7.99 | ​ | ​ | $ | 1,537,134 | ​ | ​ | 156,136 | ​ | $ | 9.84 |

These exchange traded futures contracts meet the definition of derivative financial instruments.

For the effective fair value hedges, the hedged item is recognized on the balance sheet at fair value.

Changes in the fair value of the hedged balance sheet item are recognized as an offset against the change in fair value of the derivative in cost of goods sold and included in cash flows from operations.

The fair value of the derivative instruments is disclosed in Note 7.

February 28, 2025

​

| Balances at January 1, 2022 | ​ | 194,998 | ​ | ​ | 72,227 | ​ | ​ | 649 | ​ | ​ | (2,674,267) | ​ | ​ | 1,218,933 | ​ | ​ | 7,761,417 | ​ | ​ | (2,091) | ​ | ​ | (195,884) | ​ | ​ | 6,108,757 | ​ | ​ | 211,414 |

| Dividends declared | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | (245,287) | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | (245,287) | ​ | ​ | \- |

| Noncontrolling investors, net | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | 630 | ​ | ​ | (2,495) | ​ | ​ | \- | ​ | ​ | (36,989) | ​ | ​ | (38,854) | ​ | ​ | (29,911) |

| Share repurchases | ​ | (22,996) | ​ | ​ | 22,996 | ​ | ​ | \- | ​ | ​ | (1,800,905) | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | (1,800,905) | ​ | ​ | \- |

| Equity-based compensation | ​ | 934 | ​ | ​ | (397) | ​ | ​ | 1 | ​ | ​ | 15,659 | ​ | ​ | (6,997) | ​ | ​ | (544) | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | 8,119 | ​ | ​ | \- |

| Net income | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | \- | ​ | ​ | 3,862,674 | ​ | ​ | \- | ​ | ​ | 16,818 | ​ | ​ | 3,879,492 | ​ | ​ | \- |

| Investments in unconsolidated affiliates | ​ | \- | ​ | ​ | \- | ​ | ​ | (222,480) |

Effective the fourth quarter 2024, results from an entity previously reported within the metals recycling operations segment were moved to the aluminum operations segment, consistent with a change in how the company’s chief operating decision maker manages the business.

Segment information provided within this Form 10-K, including that within Note 12.

_Segment Information_, has been recast for all prior periods consistent with the current reportable segment presentation.

The aluminum flat rolled products mill and the Mexico and US recycled aluminum slab centers are expected to begin operations in mid to late 2025.

Short-term investments held as of December 31, 2023 consisted of commercial paper ($146.2 million), US Treasuries ($564.9 million), and certificates of deposit ($10.1 million).

| ​ | ​ | ​ | ​ | 12,722,478 | ​ | ​ | 10,932,914 | ​ |

| ​ | Other | ​ | \- | ​ | ​ | 600 | ​ | ​ | ​ | ​ | ​ |

| ​ | ​ | $ | 227,234 | ​ | $ | 257,759 | ​ | ​ | ​ | ​ | ​ |

| ​ | ​ | ​ | ​ | ​ | ​ |

| --- | --- | --- | --- | --- | --- |

| ​ | 2025 | ​ | $ | 27,464 | ​ |

| ​ | 2026 | ​ | ​ | 25,562 | ​ |

| ​ | 2027 | ​ | ​ | 23,163 | ​ |

| ​ | 2028 | ​ | ​ | 21,953 | ​ |

| ​ | 2029 | ​ | ​ | 19,583 | ​ |

| ​ | Thereafter | ​ | ​ | 109,509 | ​ |

In the fourth quarter 2024, results from an entity previously included in the metals recycling operations segment were moved to the aluminum operations segment, which also resulted in $14 million of goodwill being reassigned to the aluminum operations segment based on a relative fair value allocation approach.

Segment information for 2023 has been recast consistent with the current reportable segment presentation.

Cumulative OmniSource goodwill impairment charges were $346.8 million at December 31, 2024 and 2023.

There were no anti-dilutive common stock equivalents as of and for the years ended December 31, 2023, and 2022.

| ​ | 2022 | | | | | | | | ​ |

| Basic earnings per share | $ | 3,862,674 | ​ | ​ | 183,393 | ​ | $ | 21.06 | ​ |

| Diluted earnings per share | $ | 3,862,674 | ​ | ​ | 184,622 | ​ | $ | 20.92 | ​ |

In the normal course of business, the company has derivative financial instruments in the form of forward contracts in various metallic commodities and those related to managing fluctuations in foreign exchange rates.

At the time of acquiring these financial instruments, the company designates and assigns these instruments as hedges of specific assets, liabilities or anticipated transactions.

When hedged assets or liabilities are sold or extinguished, or the anticipated transaction being hedged is no longer expected to occur, the company recognizes the gain or loss on the designated hedged financial instrument in earnings.

In November 2023, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2023-07, _Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures_, which is intended to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses.

_Segment Information_.

ASU 2023-09 also requires entities to disclose their income tax payments to international, federal, state, and local jurisdictions, among other changes.

The guidance is effective for annual periods beginning after December 15, 2024.

Early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance.

Based on this evaluation, our principal executive officer and principal financial officer concluded that, as of December 31, [removed: 2024,] [added: 2025,] the end of the period covered by this annual report, our disclosure controls and procedures were designed to provide and were effective to provide reasonable assurance that the information required to be disclosed by us in the reports we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the applicable rules and forms, and that it is accumulated and communicated to our management, including our principal executive and principal financial officer, as appropriate to allow timely decisions regarding required disclosure.

No changes in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) occurred during the fiscal quarter ended December 31, [removed: 2024,] [added: 2025,] that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

Our Management’s Report on Internal Control Over Financial Reporting, as of December 31, [removed: 2024,] [added: 2025,] can be found on page [removed: 52] [added: 51] of this Form 10-K, and the related Report of Independent Registered Public Accounting Firm, Ernst & Young LLP, can be found on page [removed: 53] [added: 52] of this Form 10-K, each of which is incorporated by reference into this Item 9A.

During the three-month period ended December 31, [removed: 2024,] [added: 2025,] none of the Company’s directors or executive officers adopted, modified or terminated a “Rule 10b5-1 trading arrangement” or a “non-Rule 10b5-1 trading arrangement” as such terms are defined under Item 408 of Regulation S-K.

The information required to be furnished pursuant to Item 10 with respect to directors, executive officers, code of ethics, insider trading policies, and audit committee financial experts is incorporated herein by reference from the section entitled “Governance of the Company” and “Proposal No. 1 – Election of Directors” in our Proxy Statement for the [removed: 2025] [added: 2026] Annual Meeting of Shareholders, which we will file with the Securities and Exchange Commission no later than 120 days after the end of our fiscal year.

The information required to be furnished pursuant to Item 11 with respect to executive compensation is incorporated herein by reference from the section entitled “Executive Compensation and Related Information” in our Proxy Statement for the [removed: 2025] [added: 2026] Annual Meeting of Shareholders, which we will file with the Securities and Exchange Commission no later than 120 days after the end of our fiscal year.

The information relating to security ownership of certain beneficial owners and management required by Item 12 is incorporated herein by reference from the section entitled “Security Ownership of Directors and Executive Officers” and “Security Ownership of Certain Beneficial Owners” in our Proxy Statement for the [removed: 2025] [added: 2026] Annual Meeting of Shareholders, which we will file with the Securities and Exchange Commission no later than 120 days after the end of our fiscal year.

The following table summarizes information about our equity compensation plans at December 31, [removed: 2024,] [added: 2025,] all of which have been approved by shareholders.

| (1) | Includes [removed: 789,312] [added: 700,684] RSUs and [removed: 241,091] [added: 182,780] DSUs issuable upon expiration of the vesting or deferral periods, which have no exercise price. |

| ​ | ​ ​ ​ | (a) | ​ ​ ​ | (b) | ​ ​ ​ | (c) |

| 2018 Plan | | 36,266 | | — | | 1,301,887 |

| 2023 Plan(1) | ​ | 883,464 | ​ | — | ​ | 5,116,225 |

| Total | ​ | 919,730 | ​ | — | ​ | 6,418,112 |

| ​ | | (a) | | (b) | | (c) |

| 2018 Plan | | 45,511 | | — | | 1,316,899 |

| 2023 Plan(1) | | 1,030,403 | | — | | 6,190,152 |

| Total | ​ | 1,075,914 | ​ | — | ​ | 7,507,051 |

The information required to be furnished pursuant to Item 13 with respect to certain relationships and related transactions is incorporated herein by reference from the sections entitled “Governance of the Company – Statement of Policy for the Review, Approval or Ratification of Transactions with Related Persons,” and “Governance of the Company – Director Independence” in our Proxy Statement for the [removed: 2025] [added: 2026] Annual Meeting of Shareholders, which we will file with the Securities and Exchange Commission no later than 120 days after the end of our fiscal year; and from Note 9.

_Transactions with Affiliated Companies_ to our consolidated financial statements as of December 31, [removed: 2024] [added: 2025,] and [removed: 2023,] [added: 2024,] and each of the three years in the periods ended December 31, [added: 2025,] 2024, [removed: 2023,] and [removed: 2022,] [added: 2023,] included in Item 8.

_Consolidated Financial Statements and Supplementary Data_ of this Form 10-K Annual Report for the fiscal year ended December 31, [removed: 2024.][added: 2025.]

The information required to be furnished pursuant to Item 14 with respect to principal accountant fees and services is incorporated herein by reference from the sections entitled “Proposal No. 2 – Ratification of the Appointment of Independent Registered Public Accounting Firm as Auditors – Audit and Non-Audit Fees” and “Proposal No. 2 – Ratification of the Appointment of Independent Registered Public Accounting Firm as Auditors – Policy on Audit Committee Pre-Approval of Audit and Permissible Non-Audit Services of Independent Registered Public Accounting Firm” in our Proxy Statement for the [removed: 2025] [added: 2026] Annual Meeting of Shareholders, which we will file with the Securities and Exchange Commission no later than 120 days after the end of our fiscal year.

_Consolidated Financial Statements and Supplementary Data_ and described in the Index on page [removed: 51] [added: 50] of this Report.

| 3.1 | [Amended and Restated Articles of Incorporation of Steel Dynamics, Inc., reflecting all amendments thereto through May 11, 2023, incorporated herein by reference from Exhibit 3.1 to our Form 10-Q filed August 8, [removed: 2023.](https://www.sec.gov/Archives/edgar/data/1022671/000155837023013968/stld-20230630xex3d1.htm)] [added: 2023 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000155837023013968/stld-20230630xex3d1.htm)] |

| 3.2 | [Amended and Restated Bylaws of Steel Dynamics, Inc., reflecting all amendments thereto through January 31, 2024, incorporated herein by reference from Exhibit 3.2 to our Form 10-K filed February 29, [removed: 2024.](https://www.sec.gov/Archives/edgar/data/1022671/000155837024002152/stld-20231231xex3d2.htm)] [added: 2024 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000155837024002152/stld-20231231xex3d2.htm)] |

| 4.1 | [Description of Common Stock, incorporated herein by reference from Exhibit 4.1 to our Form 10-K filed February 27, [removed: 2020.](https://www.sec.gov/Archives/edgar/data/1022671/000155837020001641/ex-4d1.htm)] [added: 2020 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000155837020001641/ex-4d1.htm)] |

| [removed: 4.27a] [added: 4.32] | [removed: [Indenture] [added: [First Supplemental Indenture,] dated [added: as of] December [removed: 6, 2016,] [added: 11, 2019,] relating to our issuance of [removed: $400] [added: $600] million [removed: 5.000% Senior] [added: 3.450%] Notes due [removed: 2026,] [added: 2030] among Steel Dynamics, Inc., as Issuer, [removed: the Initial Subsidiary Guarantors named therein,] and Wells Fargo Bank, National Association, as Trustee, incorporated herein by reference from Exhibit [removed: 4.27] [added: 4.2] to our Form 8-K filed December [removed: 8, 2016.](https://www.sec.gov/Archives/edgar/data/1022671/000110465916161262/a16-22813_1ex4d27.htm)] [added: 11, 2019 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465919071897/tm1924646d4_ex4-2.htm)] |

| [removed: 4.27b] [added: 4.34] | [Form of [removed: 5.000% Senior] [added: 3.450%] Notes due [removed: 2026] [added: 2030] (included in Exhibit [removed: 4.27a),] [added: 4.32),] incorporated herein by reference from Exhibit [removed: 4.27] [added: 4.4] to our Form 8-K filed December [removed: 8, 2016.](https://www.sec.gov/Archives/edgar/data/1022671/000110465916161262/a16-22813_1ex4d27.htm)] [added: 11, 2019 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465919071897/tm1924646d4_ex4-2.htm)] |

| 4.31 | [Indenture dated December 4, 2019, among Steel Dynamics, Inc., as Issuer, and Wells Fargo Bank, National Association, as Trustee, incorporated herein by reference from Exhibit 4.1 to our Registration Statement on Form S-3 [removed: (Registration No. 333-235343)] filed December 4, [removed: 2019.](https://www.sec.gov/Archives/edgar/data/1022671/000110465919069748/a19-24378_1ex4d1.htm)] [added: 2019 (File No.: 333-235343).](https://www.sec.gov/Archives/edgar/data/1022671/000110465919069748/a19-24378_1ex4d1.htm)] |

| [removed: 4.32] [added: 4.35] | [removed: [First] [added: [Second] Supplemental Indenture, dated as of [removed: December 11, 2019,] [added: June 5, 2020,] relating to our issuance of [removed: $600] [added: $500] million [removed: 3.450%] [added: 3.250%] Notes due [removed: 2030 among] [added: 2031, between] Steel Dynamics, [removed: Inc., as Issuer,] [added: Inc.] and Wells Fargo Bank, National Association, as Trustee, incorporated herein by reference from Exhibit 4.2 to our Form 8-K filed [removed: December 11, 2019.](https://www.sec.gov/Archives/edgar/data/1022671/000110465919071897/tm1924646d4_ex4-2.htm)] [added: June 5, 2020 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465920070271/tm2021405d4_ex4-2.htm)] |

| [removed: 4.34] [added: 4.37] | [Form of [removed: 3.450%] [added: 3.250%] Notes due [removed: 2030] [added: 2031] (included in Exhibit [removed: 4.32),] [added: 4.35),] incorporated herein by reference from Exhibit 4.4 to our Form 8-K filed [removed: December 11, 2019.](https://www.sec.gov/Archives/edgar/data/1022671/000110465919071897/tm1924646d4_ex4-2.htm)] [added: June 5, 2020 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465920070271/tm2021405d4_ex4-2.htm)] |

| [removed: 4.35] [added: 4.38] | [removed: [Second] [added: [Third] Supplemental Indenture, dated as of [removed: June 5,] [added: October 9,] 2020, relating to our issuance of [removed: $400] [added: $350] million [removed: 2.400%] [added: 1.650%] Notes due [removed: 2025] [added: 2027] and [removed: $500] [added: $400] million 3.250% Notes due [removed: 2031,] [added: 2050,] between Steel Dynamics, Inc. and Wells Fargo Bank, National Association, as Trustee, incorporated herein by reference from Exhibit 4.2 to our Form 8-K filed [removed: June 5, 2020.](https://www.sec.gov/Archives/edgar/data/1022671/000110465920070271/tm2021405d4_ex4-2.htm)] [added: October 9, 2020 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465920113839/tm2032546d4_ex4-2.htm)] |

| [removed: 4.36] [added: 4.45] | [Form of [removed: 2.400%] [added: 5.250%] Notes due [removed: 2025] [added: 2035] (included in Exhibit [removed: 4.35),] [added: 4.44),] incorporated herein by reference from Exhibit 4.3 to our Form 8-K filed [removed: June 5, 2020.](https://www.sec.gov/Archives/edgar/data/1022671/000110465920070271/tm2021405d4_ex4-2.htm)] [added: March 12, 2025 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465925022903/tm257874d4_ex4-2.htm)] |

| [removed: 4.37] [added: 4.40] | [Form of 3.250% Notes due [removed: 2031] [added: 2050] (included in Exhibit [removed: 4.35),] [added: 4.38),] incorporated herein by reference from Exhibit 4.4 to our Form 8-K filed [removed: June 5, 2020.](https://www.sec.gov/Archives/edgar/data/1022671/000110465920070271/tm2021405d4_ex4-2.htm)] [added: October 9, 2020 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465920113839/tm2032546d4_ex4-2.htm)] |

| [removed: 4.38] [added: 4.42] | [removed: [Third] [added: [First] Supplemental Indenture, dated as of [removed: October 9, 2020,] [added: July 3, 2024,] relating to our issuance of [removed: $350 million 1.650% Notes due 2027 and $400] [added: $600] million [removed: 3.250%] [added: 5.375%] Notes due [removed: 2050,] [added: 2034,] between Steel Dynamics, Inc. and [removed: Wells Fargo Bank,] [added: U.S. Bank Trust Company,] National Association, as Trustee, incorporated herein by reference from Exhibit 4.2 to our Form 8-K filed [removed: October 9, 2020.](https://www.sec.gov/Archives/edgar/data/1022671/000110465920113839/tm2032546d4_ex4-2.htm)] [added: July 5, 2024 (File No. 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465924078017/tm2418907d1_ex4-2.htm)] |

| 4.39 | [Form of 1.650% Notes due 2027 (included in Exhibit 4.38), incorporated herein by reference from Exhibit 4.3 to our Form 8-K filed October 9, [removed: 2020.](https://www.sec.gov/Archives/edgar/data/1022671/000110465920113839/tm2032546d4_ex4-2.htm)] [added: 2020 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465920113839/tm2032546d4_ex4-2.htm)] |

| [removed: 4.40] [added: 4.46] | [Form of [removed: 3.250%] [added: 5.750%] Notes due [removed: 2050] [added: 2055] (included in Exhibit [removed: 4.38),] [added: 4.44),] incorporated herein by reference from Exhibit 4.4 to our Form 8-K filed [removed: October 9, 2020.](https://www.sec.gov/Archives/edgar/data/1022671/000110465920113839/tm2032546d4_ex4-2.htm)] [added: March 12, 2025 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465925022903/tm257874d4_ex4-2.htm)] |

| 4.41 | [Indenture, dated as of December 7, 2022, between Steel Dynamics, Inc., as Issuer, and U.S. Bank Trust Company, National Association, as Trustee, incorporated herein by reference from Exhibit 4.1 to our Registration Statement on Form S-3 [removed: (Registration No. 333-268703)] filed December 7, [removed: 2022.](https://www.sec.gov/Archives/edgar/data/1022671/000110465922125219/tm2231991d2_ex4-1.htm)] [added: 2022 (File No.: 333-268703).](https://www.sec.gov/Archives/edgar/data/1022671/000110465922125219/tm2231991d2_ex4-1.htm)] |

| [removed: 4.42] [added: 4.44] | [removed: [First] [added: [Second] Supplemental Indenture, dated as of [removed: July 3, 2024,] [added: March 12, 2025,] relating to our issuance of [removed: $600] [added: $750] million [removed: 5.375%] [added: 5.250%] Notes due [removed: 2034,] [added: 2035 and $400 million 5.750% Notes due 2055,] between Steel Dynamics, Inc. and U.S. Bank Trust Company, National Association, as Trustee, incorporated herein by reference from Exhibit 4.2 to our Form 8-K filed [removed: July 5, 2024.](https://www.sec.gov/Archives/edgar/data/1022671/000110465924078017/tm2418907d1_ex4-2.htm)] [added: March 12, 2025 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465925022903/tm257874d4_ex4-2.htm)] |

| 4.43 | [Form of 5.375% Notes due 2034 (included in Exhibit 4.42), incorporated herein by reference from Exhibit 4.3 to our Form 8-K filed July 5, [removed: 2024.](https://www.sec.gov/Archives/edgar/data/1022671/000110465924078017/tm2418907d1_ex4-2.htm)] [added: 2024 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465924078017/tm2418907d1_ex4-2.htm)] |

| 10.20† | [Steel Dynamics, Inc., Change in Control Benefit Plan, incorporated herein by reference from our Exhibit 10.20 to our 8-K filed December 4, [removed: 2012.](https://www.sec.gov/Archives/edgar/data/1022671/000110465912081791/a12-28484_2ex10d20.htm)] [added: 2012 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465912081791/a12-28484_2ex10d20.htm)] |

| 10.61† | [2018 Executive Incentive Compensation Plan, approved by stockholders on May 17, 2018, incorporated herein by reference from our [removed: May 17, 2018, Notice of Annual Meeting of Stockholders] [added: Definitive Proxy Statement on Schedule 14A] filed March 28, [removed: 2018.](https://www.sec.gov/Archives/edgar/data/1022671/000104746918002209/a2235065zdef14a.htm)] [added: 2018 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000104746918002209/a2235065zdef14a.htm)] |

| 10.62 | [Credit Agreement dated as of July 19, 2023, among Steel Dynamics, Inc. and the agents and lenders named therein, incorporated herein by reference from Exhibit 10.62 to our Form 8-K filed July 21, [removed: 2023.](https://www.sec.gov/Archives/edgar/data/1022671/000110465923082924/tm2321771d1_10-62.htm)] [added: 2023 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465923082924/tm2321771d1_10-62.htm)] |

| 10.63† | [Steel Dynamics, Inc. 2023 Equity Incentive Plan, [removed: as] approved by stockholders on May 11, 2023, incorporated herein by reference from our [removed: Notice of 2023 Annual Meeting &] [added: Definitive] Proxy Statement [added: on Schedule 14A] filed March 30, [removed: 2023.](https://www.sec.gov/ix?doc=/Archives/edgar/data/1022671/000110465923039039/tm231847d2_def14a.htm)] [added: 2023 (File No.: 000-21719).](https://www.sec.gov/ix?doc=/Archives/edgar/data/1022671/000110465923039039/tm231847d2_def14a.htm)] |

| 10.64† | [Steel Dynamics, Inc. 2024 Employee Stock Purchase Plan, [added: approved by stockholders on May 9, 2024,] incorporated herein by reference from our Definitive Proxy Statement on Schedule 14A filed March 28, [removed: 2024.](https://www.sec.gov/ix?doc=/Archives/edgar/data/1022671/000110465924040422/tm242683d2_def14a.htm)] [added: 2024 (File No.: 000-21719).](https://www.sec.gov/ix?doc=/Archives/edgar/data/1022671/000110465924040422/tm242683d2_def14a.htm)] |

| [removed: 19.1*] [added: 19.1] | [Policy Regarding Insider Trading and Certain Prohibited [removed: Transactions](https://www.sec.gov/Archives/edgar/data/1022671/000155837025001886/stld-20241231xex19d1.htm).] [added: Transactions, incorporated herein by reference from Exhibit 19.1 to our Form 10-K filed February 28, 2025 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000155837025001886/stld-20241231xex19d1.htm)] |

| 21.1* | [List of our [removed: Subsidiaries.](https://www.sec.gov/Archives/edgar/data/1022671/000155837025001886/stld-20241231xex21d1.htm)] [added: Subsidiaries.](https://www.sec.gov/Archives/edgar/data/1022671/000110465926021395/stld-20251231xex21.htm)] |

| 23.1* | [Consent of Ernst & Young [removed: LLP.](https://www.sec.gov/Archives/edgar/data/1022671/000155837025001886/stld-20241231xex23d1.htm)] [added: LLP.](https://www.sec.gov/Archives/edgar/data/1022671/000110465926021395/stld-20251231xex23.htm)] |

| 24.1 | [Powers of attorney (see signature pages on pages [removed: 89 and] 90 [added: and 91] of this Report).](#POWEROFATTORNEY_980144) |

| 97.1 | [Policy on Recoupment of Executive Officer Incentive-Based Compensation In the Event of Restatements, incorporated herein by reference from Exhibit 97.1 to our Form 10-K filed February 29, [removed: 2024.](https://www.sec.gov/Archives/edgar/data/1022671/000155837024002152/stld-20231231xex97d1.htm#Exhibit:https://www.sec.gov/Archives/edgar/data/1022671/000155837024002152/stld-20231231xex97d1.htm)] [added: 2024 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000155837024002152/stld-20231231xex97d1.htm#Exhibit:https://www.sec.gov/Archives/edgar/data/1022671/000155837024002152/stld-20231231xex97d1.htm)] |

| 31.1* | [Certification of Chief Executive Officer required by Item 307 of Regulation S-K as promulgated by the Securities and Exchange Commission and pursuant to Section 302 of the Sarbanes-Oxley Act of [removed: 2002.](https://www.sec.gov/Archives/edgar/data/1022671/000155837025001886/stld-20241231xex31d1.htm)] [added: 2002.](https://www.sec.gov/Archives/edgar/data/1022671/000110465926021395/stld-20251231xex31d1.htm)] |

| 31.2* | [Certification of Chief Financial Officer required by Item 307 of Regulation S-K as promulgated by the Securities and Exchange Commission and pursuant to Section 302 of the Sarbanes-Oxley Act of [removed: 2002.](https://www.sec.gov/Archives/edgar/data/1022671/000155837025001886/stld-20241231xex31d2.htm)] [added: 2002.](https://www.sec.gov/Archives/edgar/data/1022671/000110465926021395/stld-20251231xex31d2.htm)] |

| 32.1* | [Certification of Chief Executive Officer Pursuant to 18 U.S.C Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of [removed: 2002.](https://www.sec.gov/Archives/edgar/data/1022671/000155837025001886/stld-20241231xex32d1.htm)] [added: 2002.](https://www.sec.gov/Archives/edgar/data/1022671/000110465926021395/stld-20251231xex32d1.htm)] |

| 32.2* | [Certification of Chief Financial Officer Pursuant to 18 U.S.C Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of [removed: 2002.](https://www.sec.gov/Archives/edgar/data/1022671/000155837025001886/stld-20241231xex32d2.htm)] [added: 2002.](https://www.sec.gov/Archives/edgar/data/1022671/000110465926021395/stld-20251231xex32d2.htm)] |

Wagler, either of whom may act without the joinder of the other, as his or her true and lawful attorneys-in-fact and agents with full power of substitution and resubstitution, for him or her, and in his or her name, place and stead, in any and all capacities to sign any and all amendments, and supplements to this [removed: 2024] [added: 2025] Annual Report on Form 10-K, filed pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended, and to file the same, with all exhibits thereto, and all other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and performs each and every act and thing requisite and necessary to be done, as full to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or their substitute or substitutes may lawfully do or cause to be done by virtue thereof.

Pursuant to the requirements of the Securities Exchange Act of 1934, this [removed: 2024] [added: 2025] Annual Report on Form 10-K has been signed below by the following persons on behalf of Steel Dynamics, Inc. and in the capacities and on the dates indicated.

| _/s/_ MARK D. MILLETT | Chairman and Chief Executive Officer | February [removed: 28, 2025] [added: 27, 2026] |

| _/s/_ THERESA E. WAGLER | Executive Vice President and Chief Financial Officer | February [removed: 28, 2025] [added: 27, 2026] |

| _/s/_ SHEREE L. BARGABOS | Director | February [removed: 28, 2025] [added: 27, 2026] |

| _/s/_ KENNETH W. CORNEW | Director | February [removed: 28, 2025] [added: 27, 2026] |

| _/s/_ TRACI M. DOLAN | Director | February [removed: 28, 2025] [added: 27, 2026] |

| _/s/_ JENNIFER L HAMANN | Director | February [removed: 28, 2025] [added: 27, 2026] |

| _/s/_ BRADLEY S. SEAMAN | Director | February [removed: 28, 2025] [added: 27, 2026] |

| 4.47 | [Third Supplemental Indenture, dated as of November 21, 2025, related to our issuance of $650 million 4.000% Notes due 2028, between Steel Dynamics, Inc. and U.S. Bank Trust Company, National Association, as Trustee, incorporated herein by reference from Exhibit 4.3 to our Form 8-K filed November 21, 2025 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465925114956/tm2531907d1_ex4-3.htm) |

| 4.48 | [Form of 4.000% Notes due 2028 (included in Exhibit 4.47), incorporated herein by reference from Exhibit 4.4 to our Form 8-K filed November 21, 2025 (File No.: 000-21719).](https://www.sec.gov/Archives/edgar/data/1022671/000110465925114956/tm2531907d1_ex4-3.htm) |

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| February 27, 2026 | ​ | |

| February 28, 2025 | ​ | |