NAICS codes look like bureaucratic trivia until you realize how much they control. The codes you claim determine whether you count as a small business, which set-asides you can compete for, and which opportunities even surface for you. This guide explains how NAICS codes drive size standards, set-asides, and the work you can win, and how to pick your primary code.
What is a NAICS code?
NAICS stands for the North American Industry Classification System. It is a numbering system that classifies businesses by the type of economic activity they perform. Each code is up to six digits, moving from broad sectors to specific industries. The federal government uses NAICS codes to organize procurement, so every solicitation is tagged with the code that best describes the work being bought.
For a contractor, your NAICS codes are how the government understands what you do. They are part of your SAM.gov registration, and they feed directly into how you are evaluated for small-business status and set-asides.
Why NAICS codes matter so much
The codes are not just labels. They drive three decisions that shape your entire federal strategy.
- Size standards: Each NAICS code carries an SBA size standard, expressed as either a maximum number of employees or maximum average annual receipts. Whether you are small depends on the code in question.
- Set-aside eligibility: A solicitation set aside for small business is judged against the size standard for that solicitation's NAICS code. The same firm can be small under one code and other than small under another.
- Opportunity matching: Buyers and search tools filter opportunities by NAICS. If your codes do not cover the work you do, relevant solicitations may never reach you.
Key terms, defined
- Primary NAICS code
- The single code that best represents your principal line of business. It signals your core capability and can affect certain size determinations and program eligibility.
- SBA size standard
- The threshold, set per NAICS code, below which a business qualifies as small. It is stated as a number of employees or as average annual receipts, depending on the industry.
- Other than small
- The status of a business that exceeds the size standard for a given code. It is code-specific, so it can apply to some of your codes and not others.
How to choose your primary NAICS code
Your primary code should reflect the work that generates most of your revenue and that you most want to win in the federal market. Choosing it well is worth real thought, because it shapes how buyers see you and how your size is assessed. If you are still mapping out the whole path, our guide on how to win your first federal contract puts code selection in context with the rest of the steps.
- Start from the work, not the wish. Identify what you actually deliver and how customers describe it, then find the NAICS code that matches that activity most precisely.
- Check the size standard. Look up the SBA size standard for each candidate code and confirm where your business falls. The standard can differ meaningfully between closely related codes.
- Look at where the work is bought. Review public award data to see which codes your target agencies actually use for the work you want. Aligning with how buyers tag opportunities helps you surface in the right searches.
- Pick a primary, then add relevant secondaries. You can carry multiple NAICS codes. Choose the one that best represents your core business as primary, and add the others that describe work you can legitimately perform.
Choosing additional codes
Most contractors carry several NAICS codes, and that is appropriate when you genuinely perform work across multiple industries. The discipline is honesty: only claim codes for work you can actually do, since claiming a code you cannot support invites trouble during evaluation. A focused set of accurate codes serves you better than a long list that overstates your reach.
How NAICS connects to the rest of your strategy
NAICS codes do not stand alone. They interact with your set-aside certifications, your size, and the vehicles you pursue. Because the same firm can be small under one code and not another, your codes can determine which set-aside competitions are open to you. For who qualifies for the major programs, see our guide to 8(a), SDVOSB, WOSB, and HUBZone set-asides. Codes also shape which contract vehicles fit your business, a topic we cover in GWAC vs IDIQ vs GSA Schedule.
This is where the right data makes the choice easier. FedFinder lets you see which NAICS codes carry the spending in your space, who the incumbents are under each, and how opportunities map to the codes you claim. Explore the market and competitor analysis on our capabilities page, and if you are setting up from scratch, our getting started guide walks through registration and the first steps.
Frequently asked questions
How many NAICS codes can I have?
You can claim multiple codes, and most contractors do. Keep the list to industries you can genuinely perform, and designate one as your primary code.
Can my business be small under one code and large under another?
Yes. Size is determined per NAICS code against that code's specific size standard. The same firm can be small for some codes and other than small for others.
Does my primary NAICS code limit what I can bid?
No. You can bid on solicitations under any code that fits your capabilities, not only your primary one. The primary code signals your core business and can affect certain size and program determinations.
Pick the codes where you can actually win
FedFinder scores every live opportunity against your NAICS, set-asides, and agencies, so you can see which codes carry the spending in your space, who the incumbents are, and how opportunities map to your business. Start your 14-day full-access trial today. No credit card is required. Every paid plan is backed by a 30-day money-back guarantee.