NAICS 331110

Overview

The North American Industry Classification System (NAICS) is the federal standard for classifying business establishments to support collection, analysis, and publication of statistics on the U.S. economy. Developed under the auspices of the Office of Management and Budget and first implemented in 1997, NAICS is jointly maintained with Statistics Canada and Mexico’s national statistics agency and is revised every five years, most recently in 2022. ¹

NAICS 331110 covers establishments primarily engaged in direct reduction of iron ore; producing pig iron; converting pig iron into steel; making ferroalloys; making steel; making steel and manufacturing shapes (bar, plate, rod, sheet, strip, wire); and making steel and forming pipe and tube. Federal statistical programs use this industry code to compile data on primary ferrous metal production. ²

See also on G2X:

• G2X — NAICS 331110 overview: https://app.g2xchange.com/naics/331110

What this NAICS covers

• Direct reduction of iron ore into metallic iron for subsequent steelmaking. ²
• Production of pig iron in molten or solid form. ²
• Conversion of pig iron into steel via basic oxygen, electric arc, or other processes. ²
• Manufacture of ferroalloys used to modify steel properties (e.g., silicon, manganese, chromium additions). ²
• Steelmaking combined with rolling and finishing to produce plate, sheet, strip, bar, rod, wire. ²
• Steelmaking combined with forming pipe and tube. ²

Related NAICS and PSC codes

Type	Code	Descriptor
NAICS	331210	Iron and Steel Pipe and Tube Manufacturing from Purchased Steel 2
NAICS	331221	Rolled Steel Shape Manufacturing 2
NAICS	331222	Steel Wire Drawing 2
PSC	9515	Plate, Sheet, and Strip, Iron and Steel 8

Cross-references and exclusions

• Operations of coke ovens not integrated with a steel mill are classified in NAICS 32419 (Other Petroleum and Coal Products Manufacturing). ²
• Establishments primarily engaged in nonferrous superalloys (e.g., cobalt- or nickel-based) are classified under NAICS 33149. ²
• Rolling/drawing of shapes from purchased steel is covered in NAICS Industry Group 33122, not in 331110. ²

NAICS 2022 context

• NAICS is reviewed and revised in years ending in “2” and “7”; Census programs are transitioning publications to 2022 NAICS on a program-specific schedule through 2027. ⁴
• 2022 is the current NAICS vintage; users may encounter legacy U.S. industries such as 331111 and 331112 in historical materials predating the 2022 structure. ²

Selected federal statistics for NAICS 331110

• Annual Survey of Manufactures (ASM) reported 2021 value of shipments for 331110 at $118.8 billion (up 59.7% year-over-year). ⁵
• ASM reported 2020 value of shipments for 331110 at $74.9 billion. ⁶
• ASM reported 2019 value of shipments for 331110 at $93.7 billion. ⁷

Frequently asked questions

• What industries are included in NAICS 331110?
  NAICS 331110 includes direct-reduced iron, pig iron, steelmaking, ferroalloys, and steel combined with rolling/finishing or pipe and tube forming within the same establishment. It is the core industry for primary ferrous metals. ²

• Is NAICS 331110 current and recognized in federal statistics?
  Yes. NAICS is updated every five years, with the current vintage being 2022; Census programs are implementing 2022 NAICS across releases through 2027 per the published timeline. ⁴

• Where can the official label for NAICS 331110 be verified?
  Census program documentation lists 331110 as “Iron and Steel Mills and Ferroalloy Manufacturing,” confirming the 2022 code and title in current use. ³

• Are there domestic preference or specialty metal restrictions frequently relevant to steel procurements?
  For many defense buys, DFARS specialty metals rules apply (e.g., DFARS 252.225-7009 requires specialty metals to be melted/produced in the United States or qualifying countries, with defined exceptions). Always consult the solicitation clauses for applicability. ⁹

• Which PSCs commonly describe iron and steel mill products in federal purchasing data?
  Common product PSCs include 9505 (Wire, Nonelectrical, Iron and Steel), 9510 (Bars and Rods, Iron and Steel), 9515 (Plate, Sheet, and Strip, Iron and Steel), and 9520 (Structural Shapes, Iron and Steel). ⁸

Useful resources

• G2X — NAICS 331110 overview: https://app.g2xchange.com/naics/331110
• U.S. Census Bureau — Implementation of the 2022 NAICS (timeline, program adoption). ⁴
• U.S. Census Bureau — NAICS 2022 Industry 331110 detail. ²
• U.S. Census Bureau — LEHD Snapshot: value labels (includes 331110 code label). ³

References

1. U.S. Census Bureau — About Industry: NAICS background and vintages (includes 1997 adoption and updates through 2022). https://www.census.gov/topics/employment/industry-occupation/about/industry.html
2. U.S. Census Bureau — NAICS 2022 Industry 331110: Iron and Steel Mills and Ferroalloy Manufacturing. https://www.census.gov/naics/?input=331110&year=2022
3. U.S. Census Bureau — LEHD Snapshot Documentation: Selected Codebook Value Labels (includes 331110). https://lehd.ces.census.gov/data/lehd-snapshot-doc/latest/appendices/value_labels.html
4. U.S. Census Bureau — The Census Bureau’s Implementation of the 2022 NAICS (timeline and overview). https://www.census.gov/library/reference/code-lists/naics/2022/implementation-timeline.html
5. U.S. Census Bureau — 2021 Annual Survey of Manufactures press release (industry highlights). https://www.census.gov/newsroom/press-releases/2022/annual-survey-of-manufactures.html
6. U.S. Census Bureau — 2020 Annual Survey of Manufactures press release (industry highlights). https://www.census.gov/newsroom/press-releases/2021/2020-annual-survey-of-manufactures-data.html
7. U.S. Census Bureau — 2019 Annual Survey of Manufactures press release (industry highlights). https://www.census.gov/newsroom/press-releases/2021/annual-survey-of-manufactures-data.html
8. Acquisition.gov — Product and Service Codes (PSC) Manual (official names/definitions for PSCs 9505–9520). https://www.acquisition.gov/psc-manual
9. Acquisition.gov — DFARS 252.225-7009 Restriction on Acquisition of Certain Articles Containing Specialty Metals. https://www.acquisition.gov/dfars/252.225-7009-restriction-acquisition-certain-articles-containing-specialty-metals