Iron and steel industry in the United States
The U.S. is the third-largest producer of raw steel worldwide, after China and India, and is ranked sixth in pig iron production. In 2024, the industry produced over 79 million net tons of crude steel. Approximately 25% of the steel used in the U.S. is imported.
Major steel-makers in the United States include Cleveland-Cliffs, Commercial Metals Company, Nucor, Steel Dynamics, Nippon Steel, and Carpenter Technology Corporation.
Employment as of 2014 was 149,000 people employed in iron and steel mills, and 69,000 in foundries. The value of iron and steel produced in 2014 was $113billion. As of 2020, about 0.3% of the US population is employed by the steel industry, and by 2025 steel mills were only employing 83,600 people, making the industry a relatively small portion of US manufacturing despite outsize political influence.
Types of steel mills
Steel mills in the U.S. fall into two categories: traditional integrated mills that process iron ore into steel and mini-mills that melt steel scrap to produce new steel. Mini-mills now dominate U.S. steel production.Integrated steel mills
In 2017, there were 9 operating integrated steel mills in the United States, down from 13 in 2000. Integrated mills produced 31% of the steel produced in the US.In an integrated steel mill, iron ore is reduced to metallic iron. In the US, this is done in blast furnaces and since 2014 again using direct reduced iron furnaces in Nucor's plant in Louisiana as well as another DRI plant in Texas by Voestalpine. Some of the iron from the blast furnaces is converted to steel; today this is done in basic oxygen furnaces. Iron ore, coke, and flux are fed into the blast furnace and heated. The coke reduces the iron oxide in the ore to metallic iron, and the molten mass separates into slag and iron. Some of the iron from the blast furnace is cooled, and marketed as pig iron; the rest flows into basic oxygen furnaces, where it is converted into steel. Iron and steel scrap may be added to both the blast furnace and the basic iron furnace.
US Steel operates a number of integrated steel mills, including the Gary Works in Gary, Indiana. They also operate the Edgar Thomson Works, which is the iron- and steel-making unit of the Mon Valley Works, which includes three other related plants. The company operates the Great Lakes Works, and Granite City Works.
Cleveland-Cliffs operates every integrated steel mill: in East Chicago, Indiana, Burns Harbor, Indiana, and Cleveland, Ohio.
The Ashland Works was demolished.
Current integrated steel mills in the US
| Name | Location | Owner | Status and Date |
| Gary Works | Gary, Indiana | US Steel | Operating, February 2015 |
| Mon Valley Works - Irvin Plant, Edgar Thomson Steel Works | North Braddock, Pennsylvania | US Steel | |
| Indiana Harbor Works | East Chicago, Indiana | Cleveland-Cliffs | |
| Burns Harbor Works | Burns Harbor, Indiana | Cleveland-Cliffs | |
| Middletown Works | Middletown, Ohio | Cleveland-Cliffs | |
| Cleveland Works | Cleveland, Ohio | Cleveland-Cliffs | |
| Dearborn Works | Dearborn, Michigan | Cleveland-Cliffs | One operating blast furnace Formerly Severstal Dearborn Previously Rouge Steel Previously Ford Rouge Plant |
| Great Lakes Works | River Rouge and Ecorse, Michigan | US Steel | Blast furnace and iron production idled December 2019. Automotive finishing lines remain open as of 2024. |
| Granite City Works | Granite City, Illinois | US Steel | Resumed operation 2018 Idled indefinitely in 2023. |
| Fairfield Works | Fairfield, Alabama | US Steel | Blast furnace closed permanently in August 2015. Electric arc furnace opened in 2020 and is currently operating as of 2024. |
Specialty steel mills / minimills
There were about 112 minimills or specialty mills in the US, which in 2013 produced 59% of US total steel production. The specialty mills use iron and steel scrap, rather than iron ore, as feedstock, and melt the scrap in electric furnaces.Notable Specialty and Mini-Mills in the US
| Name | Location | Owner | Status and Date |
| Brackenridge Works | Brackenridge, Pennsylvania | Allegheny Technologies | |
| former Colorado Fuel and Iron plant | Pueblo, Colorado | Oregon Steel Mills | Former integrated mill |
| Evraz Claymont Steel | Claymont, Delaware | Evraz Group | Closed |
| Mississippi Steel | Flowood, Mississippi | Nucor | |
| Butler Works | Butler, Pennsylvania | Cleveland-Cliffs, Inc. | Grain Oriented Electrical Steel |
Raw materials
The two main inputs into iron- and steel-making are a source of iron and a source of energy. Additional requirements are a fluxing material to remove the impurities, and alloy metals to give particular properties to the metal.'''Raw materials used in US iron and steel production, 2012'''
Iron and steel scrap
Two-thirds of the iron and steel produced in the US is made from recycled scrap, rather than from iron ore. In 2014, 81million mt of iron and steel were produced from scrap. Most steel from scrap is produced using electric arc furnaces.Coke
Coke, derived from coking coal, reduces iron ore to metallic iron.Flux
Flux materials, like lime, are added to the furnace to lower the melting point and remove impurities as slag. Other common fluxes include dolomite, soda ash, and fluorspar.Alloy metals
Other metals are commonly added to steel to produce alloy steels of various types. Common alloy metals are manganese, nickel, molybdenum, chromium, and vanadium. Stainless steel commonly contains a minimum of 10.5% chromium, and may also contain significant amounts of nickel or molybdenum.Slag
Slag, a byproduct of iron and steel-making composed primarily of highly impure glass, would normally be a waste product. However, it is in demand as an aggregate in concrete, asphalt paving, and construction fill. In 2014, the industry produced and marketed about 16.0million mt of slag, worth an estimated $270million.International trade
Since the 1960s, the U.S. has been a major importer of steel. In 2014, it exported 11 million tons but imported 39 million tons, with net imports making up 17% of consumption.Since the 1800s, the US steel industry has generally had a history of supporting tariffs on foreign steel imports, which Bloomberg has described as a "the reward delivered...in a patronage system" tied to a general tendency for heavy industry to favor economic protectionism. Presidents from both the Republican and Democratic parties have been known to cooperate with these demands. This has been cited as a contributing factor in Biden administration's skepticism towards the 2023-2024 proposed acquisition of U.S. Steel by Nippon Steel.
Tariffs instituted during the first term of President Donald Trump starting in 2019, which some of the biggest corporate steel buyers in the country criticized for their inclusion of exemptions, succeeded at increasing investment in the country's steel industry, but did not fare well in terms of job creation. Bloomberg has also argued that evidence suggests those tariffs led to a recession in the US manufacturing industry as a whole via rising prices.
Following the 2024 U.S. presidential election, the U.S. steel industry actively advocated for stronger trade protections, including reimposing tariffs on steel imports from the United Kingdom, European Union, and Japan to address trade-distorting practices. The industry argued that steel tariffs imposed in 2018 boosted steel prices, profits, and employment. They have also publicly called for stricter enforcement of trade laws and increased tariffs on steel-intensive products from China and Southeast Asia.