Analysis
NAICS 331110 is the 2022 national industry for iron and steel mills and ferroalloy manufacturing, part of 33111 (Iron and Steel Mills and Ferroalloy Manufacturing). Census lists 91 example activities under it in the official index.
County Business Patterns counts 359 US establishments in this code in 2023, employing 78,532 people at an average annual payroll of $116,063 per employee (90th percentile of national industries). 32% of the establishments have fewer than five employees, which is close to the national mix.
Between 2018 and 2023 the number of establishments fell 19% and employment fell 11%. The 2018 count used NAICS 2017, so part of a large move can come from codes being redefined rather than from businesses opening or closing.
Its index entries, the activities Census uses to assign businesses to this code, include armor plate made in iron and steel mills, axles, rolled or forged, made in iron and steel mills, balls, steel, made in iron and steel mills and bars, concrete reinforcing (rebar) made in steel mills, among 91 in all.
Its goods appear in 719 statistical lines of the US tariff schedule, mostly under headings 7304 (tubes, pipes and hollow profiles, seamless, of iron (other…), 7219 (flat-rolled products of stainless steel, of a width of 600…) and 7306 (other tubes, pipes and hollow profiles (for example, open…). That link is how import data is matched to domestic producers, for example in trade-remedy cases.
Census lists 4 related activities that belong elsewhere, most often in 324199, 331492, 331221 and 332312. Businesses that do several things are classified by their primary activity, the one that generates the most value, so check those boundaries before settling on this code.
Official definition
This industry comprises establishments primarily engaged in one or more of the following: (1) direct reduction of iron ore; (2) manufacturing pig iron in molten or solid form; (3) converting pig iron into steel; (4) making steel; (5) making steel and manufacturing shapes (e.g., bar, plate, rod, sheet, strip, wire); (6) making steel and forming pipe and tube; and (7) manufacturing electrometallurgical ferroalloys. Ferroalloys add critical elements, such as silicon and manganese for carbon steel and chromium, vanadium, tungsten, titanium, and molybdenum for low- and high-alloy metals. Ferroalloys include iron-rich alloys and more pure forms of elements added during the steel manufacturing process that alter or improve the characteristics of the metal.
Source: US Census Bureau, NAICS 2022 Manual.
Not this code if…
| The business mainly does | Use instead |
|---|---|
| Operating coke ovens | 324199 All Other Petroleum and Coal Products Manufacturing |
| Manufacturing nonferrous superalloys, such as cobalt or nickel-based superalloys | 331492 Secondary Smelting, Refining, and Alloying of Nonferrous Metal (except Copper and Aluminum) |
| Manufacturing concrete reinforcing bar by rolling and drawing steel from purchased steel | 331221 Rolled Steel Shape Manufacturing |
| Manufacturing fabricated structural metal products from concrete reinforcing bars and fabricated bar joists | 332312 Fabricated Structural Metal Manufacturing |
Index entries (91)
- Armor plate made in iron and steel mills
- Axles, rolled or forged, made in iron and steel mills
- Balls, steel, made in iron and steel mills
- Bars, concrete reinforcing (rebar) made in steel mills
- Bars, iron, made in iron and steel mills
- Bars, steel, made in iron and steel mills
- Billets, steel, made in iron and steel mills
- Blackplate made in iron and steel mills
- Blast furnaces
- Blooms, steel, made in iron and steel mills
- Car wheels, rolled steel, made in iron and steel mills
- Coke oven products made in iron and steel mills
- Concrete reinforcing bar (rebar) made in iron and steel mills
- Direct reduction of iron ore
- Electrometallurgical ferroalloy manufacturing
- Electrometallurgical steel manufacturing
- Fence posts, iron or steel, made in iron and steel mills
- Ferroalloys manufacturing
- Ferrochromium manufacturing
- Ferromanganese manufacturing
- Ferromolybdenum manufacturing
- Ferrophosphorus manufacturing
- Ferrosilicon manufacturing
- Ferrotitanium manufacturing
- Ferrotungsten manufacturing
- Ferrovanadium manufacturing
- Flakes, iron or steel, made in iron and steel mills
- Flats, iron or steel, made in iron and steel mills
- Forgings, iron or steel, made in iron and steel mills
- Frogs, iron or steel, made in iron and steel mills
- Galvanizing metals and metal formed products made in iron and steel mills
- Gun forgings made in iron and steel mills
- High percentage nonferrous alloying elements (i.e., ferroalloys) manufacturing
- Hoops made in iron and steel mills
- Hoops, galvanized, made in iron and steel mills
- Hot-rolling iron or steel products in iron and steel mills
- Ingot made in iron and steel mills
- Iron ore recovery from open hearth slag
- Iron sinter made in iron and steel mills
- Iron, pig, manufacturing