321918 — Other Millwork (including Flooring)
Description
This U.S. industry comprises establishments primarily engaged in manufacturing millwork (except wood windows, wood doors, and cut stock) (as defined in the official U.S. Census Bureau 2022 NAICS Manual).
Illustrative Examples
- Clear and finger joint wood moldings manufacturing
- Decorative wood moldings (e.g., base, chair rail, crown, shoe) manufacturing
- Ornamental woodwork (e.g., cornices, mantel) manufacturing
- Planing mills, millwork
- Stairwork (e.g., newel posts, railings, stairs, staircases), wood, manufacturing
- Wood flooring manufacturing
- Wood shutters manufacturing
Exclusions & Cross-References
- Manufacturing wood windows and doors--are classified in U.S. Industry 321911, Wood Window and Door
- Manufacturing; and
- Manufacturing cut stock, resawing lumber, and/or planing purchased lumber--are classified in U.S.
- Industry 321912, Cut Stock, Resawing Lumber, and Planing.
Overview Facts
Legacy SIC Concordance
Trace the historical mapping chain from the 1987 Standard Industrial Classification (SIC) to the modern 2022 NAICS code format.
- SIC 2421 - Sawmills and Planing Mills, General (via SIC1987:2421→NAICS1997:321918→2002:321918→2007:321918→2012:321918→2017:321918→2022:321918)
- SIC 2426 - Hardwood Dimension and Flooring Mills (via SIC1987:2426→NAICS1997:321918→2002:321918→2007:321918→2012:321918→2017:321918→2022:321918)
- SIC 2431 - Millwork (via SIC1987:2431→NAICS1997:321918→2002:321918→2007:321918→2012:321918→2017:321918→2022:321918)
Suggested Product Service Codes (Advisory)
The following Product Service Codes (PSCs) are advisory suggestions aligned with this NAICS code. Note: NAICS and PSC codes map to different dimensions of procurement (industry vs. product/service). There is no official binding 1:1 crosswalk.
- PSC 3220 — Woodworking Machines
Source: DoD DPCAP PSC Selection Tool (Ingested: 2026-06-29)
Frequently Asked Questions (FAQ)
Is NAICS code 321918 valid in 2022? ▾
Yes, 321918 is a valid 6-digit 2022 NAICS national industry code representing 'Other Millwork (including Flooring)' under Sector 31-33 in the official classification index.
What is the SBA size standard for NAICS code 321918? ▾
The Small Business Administration (SBA) has established a small business size standard of 500 employees for NAICS code 321918 (Other Millwork (including Flooring)), calculated based on employees.
What is the legacy SIC equivalent for NAICS 321918? ▾
According to official Census Bureau concordance tables, NAICS code 321918 (Other Millwork (including Flooring)) maps to legacy 1987 Standard Industrial Classification (SIC) codes: 2421 - Sawmills and Planing Mills, General, 2426 - Hardwood Dimension and Flooring Mills, 2431 - Millwork.
Related Pages & Tools
Further regulatory reference links for NAICS code 321918:
- 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.
- NAICS 321918 to SIC Crosswalk — Bidirectional mapping to legacy SIC codes (Other Millwork (including Flooring)).
- IRS PBA Code for Wood Product Manufacturing — Principal Business Activity tax reporting details.
- 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.