How to find your NAICS code

To find your NAICS code, describe what your business actually sells, find the six digit code for the activity that earns most of your revenue, and confirm it against the official NAICS 2022 definitions. The fastest route is the NAICS code calculator: describe the business in plain words and it returns the code, the title and the neighboring codes you might confuse it with.

If you already file taxes, you may have a code on record. Check Schedule C line B or the business activity code on your corporate return before you start from scratch.

Step 1: describe what you do in one sentence

Write one sentence that names the product or service, the customer and how you deliver it. "We haul refrigerated food long distance for grocery distributors." "I give management advice to small manufacturers." "We run a counter service taco shop."

NAICS classifies by how a business produces its output, so the sentence needs the verb as much as the noun. Selling furniture you buy from a factory is retail. Making the furniture is manufacturing. Arranging furniture shipments for others is transportation. Same product, three sectors.

Step 2: pick the activity that earns the most revenue

Your primary NAICS code follows revenue, not passion, not the activity on your sign and not the line of work you hope to grow into. If 70% of your sales come from installing HVAC systems and 30% from selling parts over the counter, you are 238220, plumbing, heating and air conditioning contractors.

The Census Bureau's own rule for establishments is the same: classify by the primary activity, which is generally the one that generates the most revenue. If two activities are close, pick the one you expect to lead over the next year and stay consistent.

Step 3: narrow from sector to six digits

Start with the two digit sector and work down. This is where most people go wrong, because they jump to a keyword match on a lookup site and land on a code that sounds right but describes a different process.

The NAICS codes list shows all 20 sectors with links to each one if you want to browse.

Step 4: check the code in the calculator

Put your sentence into the calculator. It reads the description the way an industry analyst would and returns the best match, plus close alternatives. Read the official definition of the code it suggests. NAICS definitions list what is included and, just as useful, what is excluded and where those businesses belong instead.

Two quick checks catch most errors:

1. The code must be six digits. A two, three, four or five digit number is a group, not a code you file.
2. The code must exist in NAICS 2022. Codes like 454110 (electronic shopping) and 511210 (software publishers) were retired in the 2022 revision.

Step 5: see where the code already appears

Your business may already be carrying a code. Look in these places and make them match.

The IRS uses a six digit list derived from NAICS with some codes grouped together, so your tax code may be a rounded version of your full NAICS code. Management consultants, for example, file under 541600 on Schedule C while NAICS splits them into 541611 through 541618. Our page on the NAICS code on your tax return covers the differences.

What to do with two lines of business

Plenty of businesses do two things. A landscaper who also plows snow. A bakery that also caters. A trucking company that also brokers loads.

Pick the primary code by revenue and use it on your tax return and loan applications. Then:

• On SAM.gov, list the secondary codes too, since you can only bid on contracts under codes in your registration.
• If the second line is large and run separately, consider whether it should be its own entity with its own code. Lenders underwrite each entity on its own industry.
• Tell your lender about both. A broker or AI matching engine can place a deal better when it knows that 40% of revenue comes from a lower risk activity.

Common mistakes

Choosing the code that sounds best. A general contractor who mostly subcontracts drywall is a drywall contractor (238310), not a commercial builder (236220). The SBA size standard and the lender appetite differ.

Using the entity type. There is no NAICS code for an LLC, a corporation or a sole proprietorship. The code describes activity. See our page on the NAICS code for an LLC.

Copying a competitor's code from a lookup site. Data providers infer codes from websites and filings, and they are often wrong. Our guide to NAICS code lookup explains why sites disagree.

Keeping a code after the business changes. If you started as a retailer and now mostly install what you sell, your code should change. Our guide on how to change your NAICS code shows where to update it.

Picking a code to avoid a restriction. Lenders and the SBA look at what the business actually does. A code that does not match the bank statements gets caught in underwriting and damages the application.

Why it matters for financing

Lenders publish appetite lists by NAICS code, price risk by industry and screen out restricted codes before a human ever reads the file. The right code puts your application in front of the lenders that like your industry. Start an application and the AI matches the deal to lenders that fund your code.