SIC 2431 to NAICS Code Crosswalk
The legacy 1987 SIC code 2431 (Millwork) maps transitively to modern U.S. Census 2022 NAICS code(s): 321911, 321918.
Concordance Concordance Mapping Asset
| Source Code | Source Industry | Target Code | Target Industry | Relation | Concordance Path |
|---|---|---|---|---|---|
| SIC 2431 | Millwork | NAICS 321911 | Wood Window and Door Manufacturing | One-to-Many | SIC1987:2431 → NAICS1997:321911 → 2002:321911 → 2007:321911 → 2012:321911 → 2017:321911 → 2022:321911 |
| SIC 2431 | Millwork | NAICS 321918 | Other Millwork (including Flooring) | One-to-Many | SIC1987:2431 → NAICS1997:321918 → 2002:321918 → 2007:321918 → 2012:321918 → 2017:321918 → 2022:321918 |
Why Concordances Don't Line Up 1:1
The Standard Industrial Classification (SIC) system was established in 1937 and last updated in 1987, organizing businesses by end products. The North American Industry Classification System (NAICS) replaced it in 1997, classifying establishments by production processes. Because of this structural shift, many-to-many relationships are common, requiring chained concordance steps to bridge the historical gap.
Reverse Crosswalk: Going the other way? See the mapping at NAICS 321911 to SIC, NAICS 321918 to SIC.
Related Pages & Tools
- SIC Code 2431 Profile — Legacy OSHA definition and associated industrial metadata.
- SIC Major Group 24 Hub — Legacy category group directory.
- Interactive Crosswalk Engine — Convert any SIC or NAICS code dynamically.
Primary Ingestion Source
Data sourced from the U.S. Census Bureau Concordances (1997, 2002, 2007, 2012, 2017, and 2022 editions). Last verified on 2026-06-30.