NAICS Code for General Construction: How to Find and Use the Right Code on SAM.gov

The NAICS code for general construction is typically 236220 (General Contractor of Buildings). However, the exact code depends on your primary type of construction work—whether that's residential, commercial, heavy civil, or specialized trades. Selecting the correct NAICS code on SAM.gov determines which federal solicitations your firm sees and which agencies can find you to bid.

Why NAICS Codes Matter for Federal Contracting

Every contractor in the federal marketplace operates under a NAICS code. The North American Industry Classification System (NAICS) is maintained by the Census Bureau and is the standard way the government categorizes businesses. On SAM.gov (System for Award Management), agencies post solicitations and tag them with specific NAICS codes they want to reach. If your firm doesn't register under the correct NAICS, you won't see the contracts you're actually qualified to bid on.

For small government contractors, this is especially critical. A general construction firm that registers under the wrong NAICS—say, a narrow specialty trade code instead of general contractor—will miss 80% of the work posted for their market. The reverse problem also happens: contractors register too broadly, then spend hours sorting through irrelevant opportunities.

Primary NAICS Codes for Construction Contractors

The construction industry is split across several NAICS codes. Here are the ones most commonly used by firms that already have federal experience:

Most federal construction contracts specify one or more of these codes. If your firm does general commercial building work, 236220 is the standard choice. If you also do heavy civil projects, you may register under multiple NAICS codes on SAM.gov to capture both categories.

How to Verify and Register Your NAICS Code on SAM.gov

Your NAICS code registration on SAM.gov is part of your entity registration. When you set up your SAM account, you declare your primary NAICS and can add up to 19 additional codes. Here's the practical sequence most contractors follow:

1. Determine your primary code. Look at the revenue breakdown of the last two years. Which single NAICS category represents your biggest volume? That's typically your primary code. If you're roughly split, pick the one where you perform the actual construction work (not just overhead or administration).
2. Identify secondary codes. If you regularly bid work in other categories—say, 50% building work (236220) and 30% site prep (238910)—add those as additional NAICS codes during registration. The government's system lets you list up to 20.
3. Update SAM every two years. Your SAM registration requires renewal. When you renew, review your NAICS selections. Many contractors find their business mix has shifted; keeping codes current keeps your solicitation feed accurate.
4. Test your selection on search. Log into SAM.gov, go to the Opportunities section, and filter by your NAICS code. Scan the results. If you see mostly work your firm would pursue, you've chosen correctly. If you see nothing relevant, you may have picked too narrow a code. If you see work that doesn't fit your capability, the code may be too broad.

Common NAICS Code Mistakes and How to Avoid Them

After a contractor is registered, the single biggest mistake is misalignment between the codes on file and the actual solicitations. Here's why this happens and how to catch it:

Mistake 1: Registering under a specialty code when you do general construction. A firm that does 70% general commercial building work but also does some electrical work might register under "Electrical Contractors" (238210) because someone on the team was thinking about that 30%. They end up seeing mostly specialty electrical jobs, miss the general contractor opportunities, and complain that SAM.gov "doesn't show federal work anymore."

Mistake 2: Never reviewing the code after the first registration. A firm was originally licensed as a painting contractor. They pivot to full building construction, but nobody updates SAM.gov. Five years later, they're still registered under painting codes only, still seeing mostly paint jobs.

Mistake 3: Registering under too many codes. Some contractors think, "I'll register under 15 NAICS codes to catch everything." This usually backfires. SAM algorithms assume your firm does work in every code you list. If you're registered under 15 codes but can only credibly handle 4, you'll see a lot of irrelevant solicitations, and your win rate drops because you're bidding things you shouldn't.

The fix: Stick to 2–5 NAICS codes that genuinely reflect your business. Pull your SAM profile every 12 months, review the codes, and update if your service line has changed. Most bid managers spend an hour a month reviewing this; it pays for itself instantly.

NAICS Codes and SAM.gov Solicitation Tracking

Once your NAICS codes are set correctly, they control what solicitations appear in your SAM.gov feed. Federal agencies use NAICS codes as one of their primary search filters when posting construction work. For example, the General Services Administration (GSA) posts building renovation projects under 236220. The Army Corps of Engineers posts water infrastructure work under 237110. The Department of Veterans Affairs posts facility maintenance and construction under 236220 and 238990.

A firm with the right NAICS codes can spot opportunities as soon as they're posted. A firm with the wrong codes can miss the entire funding window. For small government contractors with limited capture team resources, keeping NAICS codes current is one of the highest-ROI administrative tasks you can do.

If you're tracking multiple solicitations across different agencies and keyword categories (not just NAICS), tools like BidWatch automate the work. Rather than manually logging into SAM.gov daily, you can set up alerts for your NAICS codes plus specific keywords, then get notified at T-21, T-13, T-7, and T-3 days before deadlines close. This eliminates the scramble to respond in the last week and gives your team time to evaluate fit.

Frequently Asked Questions

Can I change my NAICS code after I'm registered on SAM.gov?

Yes. During your SAM registration renewal (every two years), you can update your NAICS codes. Between renewals, you can also submit an entity update through your SAM account. Changes typically take 1–3 business days to process. If you've pivoted your business significantly, don't wait for the renewal; update it immediately so you start seeing relevant solicitations sooner.

If I register under multiple NAICS codes, will agencies assume I can do all of them equally well?

Yes, generally. When an agency filters SAM by NAICS code, they see your firm if you list that code, period. They don't know the percentage of work you do in that category or whether it's new for you. This is why it's important to list only the codes where you have real capability and recent experience. If you're bidding under a NAICS code for the first time, be prepared to document your experience in that category (past contracts, team resumes, references) in your proposal.

What happens if I pick the wrong NAICS code and miss contract opportunities?

You simply won't see them in your SAM feed. The opportunities are posted; you just don't get notified. This is why the first audit most new federal contractors do is verify their NAICS codes against the solicitations they know they should be eligible for. If you've noticed a specific type of work (e.g., VA construction projects or GSA schedule work) that you're not seeing, the NAICS code is usually the culprit.

Do I need a separate NAICS code for federal work versus commercial work?

No. Your NAICS code applies to your entire business, whether you're pursuing federal, state, local, or commercial contracts. However, for federal purposes (SAM registration, set-asides, small-business classification), the code you declare is what matters. If you do both federal and commercial work under the same company, use the NAICS that represents your majority revenue or primary capability, since that's what the government sees.