NAICS Code 237990 — Other Heavy and Civil Engineering Construction

National Industry in the official 2022 North American Industry Classification System (U.S. Census Bureau). It is the only national industry under 23799 (Other Heavy and Civil Engineering Construction).

Code	237990
Title	Other Heavy and Civil Engineering Construction
Level	National Industry (6-digit)
Edition	NAICS 2022 edition
SBA size standard	$45 million in average annual receipts

Official definition (2022 NAICS)

This industry comprises establishments primarily engaged in heavy and civil engineering construction projects (excluding highway, street, bridge, and distribution line construction). The work performed may include new work, reconstruction, rehabilitation, and repairs. Specialty trade contractors are included in this industry if they are engaged in activities primarily related to heavy and civil engineering construction projects (excluding highway, street, bridge, distribution line, oil and gas structure, and utilities building and structure construction). Construction projects involving water resources (e.g., dredging and land drainage), development of marine facilities, and projects involving open space improvement (e.g., parks and trails) are included in this industry.

Illustrative Examples:

Channel construction

Land drainage contractors

Dam construction

Marine construction

Dock construction

Microtunneling contractors

Dredging (e.g., canal, channel, ditch, waterway)

Nuclear waste disposal site construction

Earth retention system construction

Flood control project construction

Park ground and recreational open space improvement construction

Railroad construction

Golf course construction

Subway construction

Horizontal drilling (e.g., cable, pipeline, sewer installation)

Trenching, underwater

Hydroelectric generating station construction

Tunnel construction

Is a business under 237990 "small"?

Under the SBA size standards (13 CFR 121.201, effective March 17, 2023), a business classified in NAICS 237990 qualifies as a small business if it does not exceed $45 million in average annual receipts. Small-business status determines eligibility for federal set-aside contracts, SAM.gov certifications and SBA loan programs — receipts are averaged over the latest 5 fiscal years.

Where 237990 sits in the hierarchy

Level	Code	Title
Sector	23	Construction
Subsector	237	Heavy and Civil Engineering Construction
Industry Group	2379	Other Heavy and Civil Engineering Construction
NAICS Industry	23799	Other Heavy and Civil Engineering Construction
National Industry	237990	Other Heavy and Civil Engineering Construction

Related SIC codes

Via the official U.S. Census concordance (1987 SIC ↔ NAICS), shown only where the industry definition is unchanged in NAICS 2022.

SIC code	Title
1622	Bridge, Tunnel, and Elevated Highway Construction
1629	Heavy Construction, Not Elsewhere Classified
1799	Special Trade Contractors, Not Elsewhere Classified
8741	Management Services

Data: official 2022 NAICS structure, descriptions and Census concordances, U.S. Census Bureau — U.S. government works in the public domain (17 U.S.C. §105). Suggested reference, not an official determination.