NAICS Codes for Government Contracting: How to Pick the Right Ones

Why NAICS codes matter more than most contractors think

Each NAICS code carries its own SBA size standard — either annual revenue or employee count. A company can be a small business under NAICS 541512 (Custom Computer Programming Services, $34M revenue limit) but not under NAICS 541330 (Engineering Services, $25.5M). Getting your primary NAICS wrong means your size certifications in SAM.gov are miscalibrated, which creates compliance risk on every set-aside bid you submit.

Step 1: Start with what you actually deliver

Write a plain-English description of your core service or product. Not your marketing tagline — the literal work you perform. "We build and maintain custom software applications for federal agencies" is more useful than "We deliver innovative digital transformation solutions." From that description, search naics.com or the Census Bureau's NAICS search at census.gov/naics. Read the official index entries, not just the code titles.

Step 2: Verify the SBA size standard for each candidate code

Go to sba.gov/document/support-table-size-standards. Look up each code you are considering. Size standards change periodically — always verify against the current table, not a screenshot from a blog post. Note whether the standard is revenue-based or employee-count-based. Your firm must fall below the applicable threshold to claim small business status under that code.

Step 3: Choose one primary, up to five secondary

Your primary NAICS code is the one that best represents what you bid under most often — it affects your size determination on most solicitations. Secondary codes expand the universe of solicitations where your profile matches. Most platforms and solicitations reference the primary NAICS in their set-aside determinations, so be deliberate. Don't add codes just because you theoretically could perform that work.

• Primary NAICS: the code you want to be known for, your core revenue driver in federal work
• Secondary codes: adjacent capabilities you actively pursue, not aspirational work you might take on
• Avoid adding codes where you cannot demonstrate past performance — contracting officers notice
• Re-evaluate every 12 months as your business evolves

Common pitfalls to avoid

Two mistakes show up constantly in SAM.gov registrations. First, using an overly broad code like 541990 (All Other Professional, Scientific, and Technical Services) when a more specific code exists. Specific codes rank better in searches and look more credible to contracting officers. Second, choosing a code based solely on where you see the most opportunities, rather than where you legitimately qualify — size standard fraud is a federal crime with severe penalties.