NAICS Code Lookup for Connecticut Businesses: How to Find and Use Your Code

Every Connecticut business gets asked for a NAICS code sooner or later — on a tax registration, a loan application, or a state program form. This guide walks through the NAICS code lookup step by step: how to find your code on the official Census Bureau site, where Connecticut asks for it, and what to do if you picked the wrong one.

What Is a NAICS Code?

The North American Industry Classification System (NAICS) is the standard system federal and state agencies use to classify businesses by what they do. It replaced the older Standard Industrial Classification (SIC) system in 1997 and is updated every five years, most recently in 2022.

Every code is six digits, and each digit narrows things down:

• First two digits: economic sector
• Third digit: subsector
• Fourth digit: industry group
• Fifth digit: industry
• Sixth digit: national industry (country-specific detail)

For example, code 112120 breaks down as:

• 11: Agriculture, Forestry, Fishing and Hunting (sector)
• 112: Animal Production (subsector)
• 1121: Cattle Ranching and Farming (industry group)
• 11212: Dairy Cattle and Milk Production (industry)
• 112120: Dairy Cattle and Milk Production (U.S. national industry)

NAICS Code Lookup: Step by Step

The official lookup tool is free and takes about ten minutes. Here is the process:

1. Go to the Census Bureau's NAICS page at census.gov/naics. This is the official source — you do not need a paid lookup service.
2. Search by keyword. Type a plain-English description of what your business does into the NAICS search box — "landscaping," "software," "coffee shop." The search returns candidate codes with short descriptions.
3. Read the full code descriptions. Click into the closest matches and read the detail page. Each code lists what activities it includes and cross-references similar codes it excludes. This is where most wrong picks happen — two codes can sound alike but cover different activities.
4. Browse the sector if searching stalls. If keywords are not landing, drill down instead: pick your two-digit sector (construction, retail, professional services, and so on), then narrow through subsector and industry group until you reach a six-digit code that fits.
5. Pick the code for your primary activity. If your business does several things, choose the code for the activity that produces the largest share of your revenue. You get one primary code — not one per service line.
6. Record it and use it consistently. Use the same code on your tax registration, loan applications, insurance forms, and program applications. Mismatched codes across filings invite questions.

Where Connecticut Asks for Your NAICS Code

You will run into the code in a few places:

• Business registration. When you register a new business in Connecticut, the state asks you to describe your business activity, which maps to a NAICS classification.
• Tax registration with the Department of Revenue Services. DRS uses a business activity code aligned with NAICS. Connecticut publishes Form CT-NAICS specifically to help businesses identify the six-digit code that best describes their principal activity.
• Loans, grants, and programs. SBA lenders, state grant programs, and procurement registrations typically ask for your code and may use it to screen eligibility.
• Insurance. Underwriters use your classification to price coverage such as general liability and workers' compensation.

What Happens If You Pick the Wrong Code

A wrong code is usually fixable, but it can cause real friction while it stands:

• Tax classification mismatches. Connecticut tax statutes reference NAICS codes directly. For example, Conn. Gen. Stat. § 12-407 references specific NAICS industries (532220, 812191, 812199, and 812990) for certain personal services subject to sales and use tax. A wrong code can leave you collecting the wrong taxes — or not collecting ones you should.
• Insurance misclassification. If your code suggests a riskier or safer business than you actually run, your premiums may be wrong, and a claim can get complicated.
• Program eligibility confusion. Grants, incentives, and set-aside programs often screen by code. The wrong one can disqualify you from programs you should qualify for, or invite scrutiny on ones you should not be in.
• Licensing and registration questions. Agencies may flag filings where the described activity and the code do not match.

If you discover a wrong code, correct it at the source where you reported it — update your registration with the agency, notify DRS on your next filing or by contacting them, and tell your insurance carrier. The fix is administrative, but the sooner it happens, the less unwinding there is.

Common NAICS Categories for Connecticut Small Businesses

You still need to look up your own six-digit code, but most Connecticut small businesses land in a handful of sectors:

• Construction and trades (sector 23): general contractors, electricians, plumbers, remodelers.
• Professional, scientific, and technical services (sector 54): consultants, designers, software developers, accountants, law firms, marketing agencies.
• Retail trade (sectors 44–45): shops and online sellers.
• Accommodation and food services (sector 72): restaurants, cafes, caterers.
• Health care and social assistance (sector 62): private practices, home care agencies, childcare.
• Other services (sector 81): salons, repair shops, cleaning services.

Within each sector, the six-digit code turns on details — whether you build new or remodel, sell your own product or resell, serve on-site or deliver. That is why step 3 above (reading the full description) matters.

How Your Code Affects Connecticut Programs

Beyond taxes, your classification can affect:

• Eligibility for small business loans and grants
• Qualification for minority business enterprise programs
• Access to industry-specific incentives and tax credits
• Regulatory and reporting obligations
• Participation in state procurement opportunities

Agricultural programs are a clear example: eligibility criteria in Connecticut have been tied to having a NAICS classification beginning with "11" (Agriculture, Forestry, Fishing and Hunting), so a farm operating under a retail or services code could miss programs built for it.

Keeping Your Code Current

1. Re-check your classification when your business changes. If your main revenue source shifts — say a contractor moves into property management — your code should follow.
2. Document how you chose it. A short note on why you picked your code helps if an agency, lender, or insurer ever asks.
3. Check program criteria before applying. When a grant or program lists eligible NAICS codes, confirm yours is on the list before you invest time in the application.
4. Watch for revisions. NAICS is updated every five years. A revision can split, merge, or renumber codes in your industry.

The Takeaway

Look up your NAICS code at census.gov/naics before you register your Connecticut business, pick the code for the activity that earns the most revenue, and use that same code everywhere. If you are choosing between two codes and taxes or program eligibility hang on the answer, that is a question worth resolving before you file — a $50 consultation is enough time to sort it out.