What's the NAICS code for plumbing?
Plumbing is 238220, Plumbing, Heating, and Air-Conditioning Contractors. The Census index lists plumbers, plumbing contractors, fixture installation, drain, waste and vent systems and water heater installation there. Sewer cleaning and rodding is 562998, and septic tank pumping is 562991.
The codes, side by side
| Code | What the Census index lists | Small business size limit | New federal contracts and orders, FY2026 | Of those, under $250,000 |
|---|---|---|---|---|
| 238220 Plumbing, Heating, and Air-Conditioning Contractors | Plumbers, plumbing contractors, plumbing fixture installation, water heater installation | $19.0 million | 2,751 | 2,231 |
| 562998 All Other Miscellaneous Waste Management Services | Sewer cleaning and rodding services, grease trap cleaning, catch basin cleaning services | $16.5 million | 218 | 202 |
| 562991 Septic Tank and Related Services | Septic tank pumping (cleaning) services, portable toilet renting and servicing | $9.0 million | 1,601 | 1,544 |
Size limits are average annual revenue over the last five years, from the SBA table. Contract counts are from USAspending.gov, October 2025 to September 2026.
One code covers plumbing, heating and air conditioning, so plumbing and HVAC firms compete under the same number. Plumbing also turns up in larger contracts: in FY2026, 140 new 561210 contracts and orders and 75 under 236220 mentioned plumbing.
Other codes worth listing
- 238910 Site Preparation Contractors ($19.0 million): septic system installation.
- 236220 Commercial and Institutional Building Construction ($45.0 million): plumbing bought as part of a building project.
- 561210 Facilities Support Services ($47.0 million): plumbing upkeep in a whole-facility contract.
Agencies don't always code the same work the same way, so listing every code that fits gets more bids in front of you. Our guide to which NAICS codes to list explains how.
Common questions
What is the NAICS code for plumbers?
238220, Plumbing, Heating, and Air-Conditioning Contractors. Its size limit is $19.0 million in average annual revenue.
What NAICS code is drain and sewer cleaning?
Sewer cleaning and rodding is 562998, All Other Miscellaneous Waste Management Services. Installing drain, waste and vent piping is 238220.
See the open bids under these codes
Get a free bid-match report: open federal bids that fit your work and area, ranked by fit, with deadlines and what to watch for. It usually arrives within two business days.
Sources
- Census Bureau: 2022 NAICS index
- 13 CFR 121.201: SBA size standards
- USAspending.gov: contract awards, FY2026 (pulled Nov 2, 2026)
How we get our numbers: our sources and methods.