Federal contracts for NAICS 331491

Frequently asked questions

What is NAICS 331491?

NAICS 331491 is a 6-digit North American Industry Classification System code that federal contracting officers use to classify solicitations and confirm bidder eligibility. The Census Bureau maintains the NAICS taxonomy.

How do I bid on federal contracts as a small business in NAICS 331491?

Register your business in SAM.gov, get a UEI, and confirm your NAICS code matches the solicitation's primary NAICS. Then write a capability statement that maps your past performance to the work in the RFP. Themis automates the matching and gives you a free AI brief for every active opportunity.

Do I need a SAM.gov registration to bid?

Yes — every federal contract award above the micro-purchase threshold requires the vendor to have an active SAM.gov registration with a Unique Entity Identifier (UEI) and the relevant NAICS codes listed on the registration.

What set-asides apply to NAICS 331491?

Common federal set-asides — Small Business (SBA), 8(a), HUBZone, SDVOSB, WOSB, EDWOSB — apply per solicitation, not per NAICS code. Each opportunity declares its own set-aside; Themis displays the eligibility class on every card so you can filter to ones you qualify for.

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Browse by set-aside

See opportunities reserved for each small-business program.

• Small BusinessSBA Small Business
• 8(a)SBA 8(a) Business Development Program
• HUBZoneHUBZone
• WOSBWomen-Owned Small Business (WOSB)
• EDWOSBEconomically Disadvantaged WOSB (EDWOSB)
• SDVOSBService-Disabled Veteran-Owned Small Business (SDVOSB)
• VOSBVeteran-Owned Small Business (VOSB)