NAICS 331513

Overview

The North American Industry Classification System (NAICS) is the uniform framework federal statistical agencies use to classify business establishments for collecting, analyzing, and publishing data about the U.S. economy. Developed under the Office of Management and Budget and adopted in 1997 to replace SIC, NAICS was created jointly with Statistics Canada and Mexico’s national statistics agency to ensure cross‑country comparability; the current vintage used for new Census economic releases is NAICS 2022. ¹

NAICS 331513 — Steel Foundries (except Investment) — covers establishments primarily engaged in manufacturing steel castings other than by investment (lost‑wax) methods. Within the Foundries industry group, operations may include casting and limited post‑cast steps such as cleaning and deburring; investment casting work falls under 331512, and further manufacturing into finished products is classified by the finished product industry. ²

See also on G2X:

• G2X — NAICS 331513 overview
• G2X — NAICS 331511 Iron Foundries
• G2X — NAICS 331512 Steel Investment Foundries

What this NAICS covers

• Manufacturing steel castings using non‑investment processes (e.g., sand or other non‑investment molds). ²
• Pouring molten steel into molds to form castings produced from purchased steel. ²
• Foundry cleaning and deburring of castings produced in‑house. ²
• Producing cast steel components supplied as cast (without further machining to tight tolerances). ²
• Steel casting production performed in establishments that do not make steel but purchase it from other producers. ²
• Excludes investment casting, which is classified under 331512; excludes machining/assembly that results in a distinct finished product, which is classified by the finished product industry. ²

Related NAICS and PSC codes

Per Census NAICS cross‑references and structure. ²

Type	Code	Descriptor
NAICS	331511	Iron Foundries
NAICS	331512	Steel Investment Foundries
NAICS	33151	Ferrous Metal Foundries (industry group)
NAICS	33152	Nonferrous Metal Foundries (industry group)

Small business size standard

SBA’s small business size standard for NAICS 331513 is 700 employees (effective March 17, 2023), as listed in the SBA Table of Small Business Size Standards matched to NAICS codes. ³

Exclusions and boundary notes

• Investment (lost‑wax) steel casting is classified in NAICS 331512. ²
• If steel castings are further manufactured into finished products (e.g., extensive machining/assembly), classification shifts to the industry of the finished product. ²
• Foundries may perform cleaning and deburring of their castings; more involved precision machining to tight tolerances is classified elsewhere in Manufacturing. ²

Use in Federal statistical data (NAICS 2022)

Census economic programs are transitioning publications to the NAICS 2022 vintage; the 2022 Economic Census began releasing detailed industry statistics on a NAICS 2022 basis in 2024, with broader program adoption targeted by the end of 2027. ⁴

Frequently asked questions

• What activities are included under NAICS 331513? NAICS 331513 includes making steel castings (except investment castings) from purchased steel, with foundry steps like pouring, shakeout, cleaning, and deburring. It does not encompass investment casting, and extensive post‑cast fabrication is classified by the finished product. ²

• How does NAICS 331513 differ from 331512 and 331511? 331513 covers steel castings made by non‑investment methods. 331512 specifically covers steel investment (lost‑wax) castings. 331511 covers iron (not steel) foundries. All three purchase metal from other establishments rather than producing it. ²

• Are machining or assembly of steel castings included in NAICS 331513? Only limited foundry finishing (e.g., cleaning and deburring) is in scope. When castings are further manufactured—such as precision machining, threading, or assembly—classification moves to the NAICS for the finished product. ²

• What is the SBA small business size standard for NAICS 331513? The SBA size standard is 700 employees for NAICS 331513, effective March 17, 2023, as shown in SBA’s NAICS‑matched table of size standards. ³

• Has NAICS 2022 affected publication of data for NAICS 331513? The 2022 Economic Census began releasing results on a NAICS 2022 basis in 2024. Census plans full adoption of NAICS 2022 across programs by 2027, with guidance on timing and comparability available in the implementation materials. ⁴

Useful resources

• G2X — NAICS 331513 overview
• U.S. Census Bureau — NAICS: Introduction and code search. ¹
• U.S. Census Bureau — NAICS 3315/331513 industry definitions and cross‑references. ²
• SBA — Table of Small Business Size Standards (NAICS‑matched). ³
• U.S. Census Bureau — Implementation of NAICS 2022 (timeline and changes). ⁴

References

1. U.S. Census Bureau — NAICS main page: Introduction and search (NAICS overview and 1997 adoption). https://www.census.gov/naics
2. U.S. Census Bureau — NAICS Sector 31–33 (Manufacturing) definitions including 331513 and cross‑references. https://www.census.gov/naics/resources/archives/sect31-33.html
3. U.S. Small Business Administration — Table of Small Business Size Standards matched to NAICS (effective March 17, 2023). https://www.sba.gov/sites/default/files/2023-06/Table%20of%20Size%20Standards_Effective%20March%2017%2C%202023%20%282%29.pdf
4. U.S. Census Bureau — The Census Bureau’s Implementation of the 2022 NAICS (timeline and 2022 Economic Census adoption). https://www.census.gov/library/reference/code-lists/naics/2022/implementation-timeline.html