331511 — Iron Foundries
Description
This U.S. industry comprises establishments primarily engaged in pouring molten pig iron or iron alloys into molds to manufacture castings (e.g., cast iron manhole covers, cast iron pipe, cast iron skillets). Establishments in this industry purchase iron made in other establishments.
Exclusions & Cross-References
- Establishments primarily engaged in manufacturing iron castings and further manufacturing them into finished
- products are classified based on the specific finished product.
Overview Facts
| NAICS Code | 331511 |
|---|---|
| Industry Title | Iron Foundries |
| SBA Size Standard | 1,000 employees |
| IRS PBA Code | 331500 (rolled-up match) |
| Sectors Hierarchy | Sector 31-33 → 331 → 3315 |
| Source / Verified | US Census 2022 NAICS Manual / 2026-06-28 |
Legacy SIC Concordance
Trace the historical mapping chain from the 1987 Standard Industrial Classification (SIC) to the modern 2022 NAICS code format.
- SIC 3321 - Gray and Ductile Iron Foundries (via SIC1987:3321→NAICS1997:331511→2002:331511→2007:331511→2012:331511→2017:331511→2022:331511)
- SIC 3322 - Malleable Iron Foundries (via SIC1987:3322→NAICS1997:331511→2002:331511→2007:331511→2012:331511→2017:331511→2022:331511)
Related Resources & Compliance Guides
Further regulatory reference links for NAICS code 331511:
- Sector 31-33 Directory Hub — List of related industries in the Manufacturing sector.
- SIC ↔ NAICS Crosswalk Tool — Look up mappings between legacy SIC codes and modern classifications.
- SBA Size Standards Guide — Complete rules and averaging periods for small business classifications.
- Calculating Annual Receipts Guide — Detailed worked example of revenue calculation rules.
- IRS Principal Business Activity Guide — How NAICS codes map to corporate and entity tax filings.
Related Industries in 3315
Frequently Asked Questions (FAQ)
Is 331511 a valid 2022 NAICS code?
NAICS 331511 is 'Iron Foundries', a 2022 U.S. national industry under Sector 31-33 (Manufacturing); the SBA small-business size standard is 1,000 employees.
What is the SBA size standard for NAICS 331511?
The SBA small business size standard for NAICS 331511 is 1,000 employees (based on employees).
What is the legacy SIC code mapping for 331511?
NAICS code 331511 maps to the legacy 1987 SIC codes: 3321 - Gray and Ductile Iron Foundries, 3322 - Malleable Iron Foundries.