How to Choose NAICS Codes for Federal Contracting
A practical guide to selecting the right NAICS codes for SAM.gov — covering size standards, primary vs. secondary codes, and common mistakes.
Your NAICS codes determine your size standard, set-aside eligibility, and which opportunities match your profile. Getting them right takes 30 focused minutes and is worth every one of them.
Step-by-Step Walkthrough
- Write a plain-English description of your core service or product (what you actually do, not your marketing tagline)
- Search naics.com or census.gov/naics — read official descriptions, not just code titles
- Look up the SBA size standard for each candidate code at sba.gov/document/support-table-size-standards
- Select one primary NAICS and up to five secondary codes that you actively pursue
- Enter all codes in your SAM.gov entity registration and GovPillar Company Profile
Why primary NAICS matters more than secondary
Your primary NAICS is the code used to determine your size standard on most set-aside bids — it is the single code that defines whether you qualify as a small business for a given solicitation. Secondary codes expand the list of opportunities that match your profile, but they do not override the primary for size determination. Choose your primary based on where you actually want to win contracts, not where you see the most volume.
Size standards: reading the table correctly
Every NAICS code in the SBA table has either an annual revenue ceiling or an employee count ceiling — not both. Look up each code you are considering individually, because thresholds vary widely even within the same industry group. A $34M revenue limit under 541512 and a $25.5M limit under 541330 are both real numbers for IT and engineering services. Getting this wrong means your size certification in SAM.gov is inaccurate, which creates exposure on every set-aside bid you submit under that code.
Official Source
Always verify current requirements directly with the government.
Put this into practice
GovPillar connects your SAM.gov profile to live opportunities, scores each one with AI, and helps you manage the full capture cycle. Free to start.