Anyone can print "plumber" on a truck. In Oklahoma, though, plumbing for hire is a licensed trade, and the state gives homeowners a free way to check. Taking five minutes to look up a plumber's license before they start work is one of the simplest ways to protect your home, your permit and your wallet. This guide explains who licenses plumbers in Oklahoma, the license types you will see, how to run the lookup, where the license number should appear, why city registration matters in Tulsa and the suburbs, and when a homeowner can legally do the work themselves.
This is general information, not legal advice.
Who licenses plumbers in Oklahoma?
The Construction Industries Board (CIB) licenses plumbing in Oklahoma under the Plumbing License Law of 1955 (59 O.S. §1001 and following) and the CIB's plumbing rules (OAC 158:30). State law makes it a misdemeanor to act as a plumbing contractor, or to offer plumbing work "by advertisement or otherwise," without a CIB license. A violation carries a fine of $200 to $1,000 plus costs, and the CIB can also suspend or revoke a license.
Oklahoma plumbing license types
When you look a plumber up, you will usually see one of these:
- Plumbing contractor. The business license. A contractor can bid jobs, sign contracts and supply labor and materials. ("Master plumber" is an older title that now means plumbing contractor.)
- Journeyman plumber. A licensed individual who does the hands-on work. Under the CIB rules, a journeyman must be employed and supervised by a licensed plumbing contractor and may not contract jobs on their own.
- Unlimited or residential. Both contractor and journeyman licenses come in unlimited and residential versions. Residential licenses cover detached one- and two-family homes and townhouses of not more than three stories, which covers most Tulsa houses.
- Apprentice. Apprentices are registered with the CIB (the registration lasts one year) and must work under the direct supervision of a licensed journeyman or plumbing contractor. A licensed plumber may supervise no more than three apprentices.
What this means for you: the company you sign a contract with should hold a plumbing contractor license. The person under your sink may be a journeyman or a supervised apprentice, and that is normal.
How to run the CIB "Are They Licensed?" lookup
- Ask the plumber for their Oklahoma plumbing contractor license number and the exact business name.
- Go to the CIB's "Are They Licensed?" page at oklahoma.gov/cib and open the license search.
- Search by license number first. If that fails, search by the business or person's name.
- Check that the name matches the company on your quote, that the license is a plumbing license (not only another trade), and that it is current rather than expired.
- Note whether it is a contractor or journeyman license, and residential or unlimited.
If you cannot find the license, ask the plumber to explain. A name mismatch can be innocent (a trade name versus a legal name), but you should get a clear answer before anyone starts work.
Where the license number should appear
You often do not need to ask, because Oklahoma rules require plumbing contractors to show the number:
- Ads, bids and contracts. OAC 158:30-5-3(b) says the plumbing contractor state license number "must be displayed on all advertising, contracts, and bids." Look for it on the written quote.
- Work vehicles. Contractors must show the firm name and license number, with the initials "OK" in front of the number, in letters at least two inches tall on both sides of each vehicle.
- On the job. The plumber's pocket license must be on their person while working, so you can ask to see it.
A missing number on a bid is a reason to ask questions. It does not prove anything by itself, but a licensed contractor should be able to give you the number right away.
City registration: the step most people skip
A state license is not the whole story. Under 59 O.S. §1020, each state-licensed plumbing contractor must register with the plumbing inspector of every city and town where they work. So for a Tulsa job, ask: "Are you registered with the City of Tulsa?" For a job in Broken Arrow, Owasso, Bixby, Jenks, Sand Springs or Sapulpa, ask about that city.
Registration matters because it ties into permits. The City of Tulsa's Development Services Permit Center states: "Only a Licensed tradesperson may apply for trade permits." Tulsa's plumbing permit form lists items such as water heaters, slab leaks, reroute piping, gas piping, backflow assemblies, water service and building waste lines, so jobs like a water heater replacement or slab-leak repair are permitted work. Sand Springs says state-licensed and City-registered contractors "SHALL perform all electrical, plumbing and mechanical work," and Sapulpa says plumbing permits must be requested by state-licensed contractors registered with the City. Bixby and Jenks also expect plumbing to be done by contractors licensed or registered with the city.
The simple version: ask whether the plumber is registered with your city and whether they will pull the permit. More detail is in our guide to plumbing permits in Tulsa.
The homeowner exemption: when you can do it yourself
Oklahoma's plumbing law (59 O.S. §1017) does not apply to some work. Two exemptions matter most to homeowners:
- Minor repairs, meaning repairing or replacing faucets or minor working parts of plumbing fixtures. Swapping a toilet flapper or a faucet cartridge falls here.
- Work on your own home. An individual may do plumbing work on their own "property of residence." The CIB rules narrow that to an existing single-family home that the owner lives in as a primary home. A rental, a house you are flipping, or a relative's house does not qualify.
The exemption covers the license, not the permit. Owasso, for example, says on its permits page that homeowners doing their own plumbing still need a permit and inspection. Check with your city before you open a wall. Gas piping is separate again: under 59 O.S. §1850.10, gas piping may be installed or repaired only by a mechanical licensee or a licensed plumbing contractor or journeyman.
Before you hire: a quick checklist
- Ask for the contractor's Oklahoma plumbing contractor license number. Oklahoma rules require it on contractors' ads, bids and contracts, with "OK" in front of it on both sides of work vehicles (OAC 158:30-5-3).
- Look it up on the Construction Industries Board's "Are They Licensed?" page.
- Ask whether they are registered with your city (Tulsa, Broken Arrow, Owasso…), which 59 O.S. §1020 requires, and whether they will pull the permit.
- Get the price in writing before work starts.
- Gas smell: leave the house first, then call 911 and Oklahoma Natural Gas at 800-458-4251.
Prices matter too. Our Tulsa plumbing cost guide lists typical ranges from published cost guides, so you can tell whether a written quote is in the usual range. If water is spraying or a drain is backing up, see the emergency plumber page for what to do first, or the drain cleaning page for slow drains and sewer line trouble.
How Tulsa Plumbing Pros fits in
We connect Tulsa-area homeowners with independent, licensed local plumbing contractors for free, no-obligation quotes. The plumber you choose quotes, pulls any permit, and does the work directly with you. Whoever you hire, through us or anyone else, run the license lookup and ask about city registration first. When you are ready, request a free quote.