- SAM.gov's public entity search shows the NAICS codes a company registered. It is free and needs no account.
- The Census Bureau NAICS search works by keyword for the type of work, not by company name.
- Your primary NAICS code in SAM.gov should match the work you actually bid, because each code carries its own SBA size standard.
- Census publishes a free NAICS-to-SIC concordance, but matches are approximate, so choose the row that fits your main revenue.
- State vendor systems differ. Tennessee's Edison portal uses commodity codes, so check each state's own registration form.
You can find a company's NAICS codes in about two minutes. Search its name in SAM.gov's public entity search to see what it registered, and use the Census NAICS search when you only know the type of work. This guide shows both, then covers SIC conversion, who does what among SBA, IRS and Census, and what to do for state vendor registrations.
How do I look up a NAICS code by business name for free?
Three free tools answer different questions. SAM.gov tells you what a specific company registered. The Census search tells you which code fits a type of work. Our own NAICS code lookup suggests codes from a plain description of your business.
SAM.gov entity search
Search the company's legal name in SAM.gov's public entity search, open its registration, and look at the NAICS codes listed. This is what the company chose to report, which is what contracting officers and primes see. Most active registrations are public, but some details can be hidden.
Census NAICS search
The Census Bureau's NAICS search takes keywords such as "janitorial" or "software" and returns matching six-digit codes with full definitions. It does not look up companies by name. For a walkthrough of that tool, see our Census NAICS lookup guide.
Why the tools disagree
A company that does construction and consulting can legitimately show different codes in different places, and none of them is wrong. For your own registration, pick the code that matches the work you plan to bid, then check it against the NAICS codes on the solicitations you want. New to codes? Start with what a NAICS code is.
What is the difference between the SBA, IRS and Census NAICS lookups?
NAICS itself is published by the Office of Management and Budget. Each agency then uses it for its own job.
- Census: publishes the code lists, definitions and search tool, so it is the place to check what a code covers.
- SBA: sets a size standard for each code, which decides whether you count as small for a set-aside.
- IRS: asks for a business activity code on tax returns. It does not have to match your SAM.gov primary code.
The contracting officer picks the NAICS code for each solicitation, and that code sets the size standard you are measured against (see FAR subpart 19.1). That is why checking the size standard before you register matters. An 8(a) or SDVOSB firm that picks the wrong code can price itself out of a set-aside it should win.
How do I convert a NAICS code to a SIC code?
Some lenders, insurers and state forms still ask for a four-digit SIC code, the older system NAICS replaced in the late 1990s. Census publishes a free NAICS-to-SIC concordance. Find your six-digit NAICS code, then read across to the SIC column.
The match is approximate. Some NAICS codes map to several SIC codes, so pick the one that fits where most of your revenue comes from. If there is no clean match, use the best fit and note the assumption on the form. Federal opportunities are matched by NAICS, not SIC.
What about New York and Tennessee state vendor registration?
State systems are separate from SAM.gov, so a federal lookup will not show what a state has on file. Requirements change, so confirm each step on the state's own site.
New York
New York posts state bid opportunities on the NYS Contract Reporter, and vendors obtain a vendor ID through the Office of the State Comptroller's Vendor File System. I could not confirm that either asks for NAICS codes, so read the registration form before you assume it does. Veteran-owned and minority and women-owned certifications are separate applications.
Tennessee
Tennessee suppliers register through the Edison supplier portal. The Central Procurement Office's FAQ says you can enter commodity codes during registration or edit them after approval, and it recommends selecting every code that fits your business. Those are commodity codes, not NAICS codes. Approval can take 7 to 10 business days.
Which NAICS code should I use when registering a small business?
SAM.gov lets you name one primary NAICS code and add others. The primary code is the one SAM.gov links to your registration, and it affects your size standard. Choose the work you are actively pursuing, not the broadest description you qualify for.
Each six-digit code has its own revenue or employee threshold, which you can check in the SBA size standards tool. If a code's threshold is tight for your revenue, you could outgrow small-business status in that lane, so compare before you commit.
Relevance is judged against the work, so do not claim codes for services you have never delivered. Start with the two or three codes that cover projects you have completed, then add more as you win. Our small business guide shows how to pair codes with a capability statement.
Want a shortcut? My NAICS Code Goldmine: Find Every Set-Aside You Qualify For ($17) is on Gumroad.
Why do lookup tools return different codes for the same company?
Registrations are self-reported, and a company can list several codes. Commercial tools such as HigherGov and GovTribe pull from public records, so they show whatever the company filed, sometimes years ago. Census and the IRS classify businesses for statistics and tax purposes, which is a different job.
Trust the source that fits your purpose. For a bid, use the code on the solicitation. For taxes, use the IRS list. For market research, check the company's capability statement and its SAM.gov profile before relying on a third-party tool.
How do I verify a competitor's or partner's NAICS code?
Search the company in SAM.gov's public entity search and open its registration. You will see the NAICS codes it registered, its CAGE code and its UEI. A website claim is marketing, not registration.
Registration shows intent, and award history shows what happened. USAspending.gov lets you filter awards by recipient and see which NAICS codes appear on its actual contracts. A partner registered for 541611 that has only won 541512 work has IT past performance, not general management consulting. That gap matters when you decide whether a teaming partner adds real credibility.
Frequently Asked Questions
Is there a free NAICS code lookup by company name with no signup?
Yes. SAM.gov's public entity search shows the NAICS codes a company registered, with no account. The Census NAICS search is also free, but it works by keyword for the type of work, not by company name.
Can I change my NAICS code after registering in SAM.gov?
Yes. You can update your registration when your focus changes, and you review it when you renew each year. Keep the primary code matched to the work you actively pursue.
How many NAICS codes can I list in SAM.gov?
You name one primary code and can add others. The registration form sets the current limit, so check it when you register, and keep the list to work you can actually deliver.
Do I need a NAICS code before I get a CAGE code?
You choose your NAICS codes while completing the SAM.gov registration. The CAGE code is assigned through that same registration process, so there is no separate step to finish first.
What NAICS code do I use on a capability statement?
List the codes that match projects you have actually completed, and lead with the one closest to the solicitation you are targeting. Buyers judge relevance by the work described, not by the code alone.