NAICS Codes for Government Contracts

A NAICS code (North American Industry Classification System) is a 6-digit code that federal agencies use to classify businesses by industry. Each solicitation includes one NAICS code that determines small business size standards, set-aside eligibility, and which past performance the agency considers relevant.

Start with the services or products you provide. Use the NAICS Finder tool to search by keyword. You should register the primary NAICS that best represents your core business, plus secondary NAICS for additional capabilities. Your SAM.gov registration must include the NAICS codes you want to compete under.

Yes. You can register and compete under as many NAICS codes as accurately describe your business. SBA size standards vary by code, so you may be 'small' under some NAICS and 'other than small' under others. Always check the specific size standard on the solicitation NAICS.

The top federal NAICS by spending typically include 541330 (Engineering Services), 541512 (Computer Systems Design), 541715 (Physical/Engineering/Life Sciences R&D), 541330 (Engineering Services), 236220 (Commercial Construction), and 561210 (Facilities Support). DoD, VA, HHS, and DHS account for the majority of spending across these codes.

Yes. The NAICS code on the solicitation sets the small business size standard. Your business must qualify as small under that specific NAICS (by employee count or revenue) to bid on a small business set-aside. NAICS appeals exist if you believe the agency assigned the wrong code.