Short answer: often yes, on your own home, but permits and inspections still apply to many jobs. Here's how it works in Arizona. (This is general information, not legal advice; check with your city and the Registrar of Contractors for your situation.)
The owner-builder exemption
Arizona law (A.R.S. 32-1121) lets property owners work on their own home without a contractor's license, as long as the home is for their own use, not for sale or rent. Selling or renting the home within one year after the work is finished can be treated as evidence that the work was really for sale, and the owner can lose the exemption.
Permits still apply
The exemption is about licensing, not permits. Many plumbing jobs need a permit and an inspection from your city no matter who does them, especially:
- Replacing or adding a water heater.
- New drain, waste or vent lines, or moving fixtures.
- Sewer line work.
- Gas lines.
- Repiping.
In Mesa, permits go through the city's Development Services department, and Mesa has used the 2024 International Plumbing Code since January 8, 2026. Other cities have their own departments and rules, so check before you start.
You can't hire an unlicensed "handyman" for big jobs
If someone else does the work for pay, Arizona's handyman exemption is narrow: work of a casual or minor nature, generally under $1,000 including labor and materials, and nothing that needs a permit. Anything bigger needs a licensed contractor. See how to know if a plumber is good to check a license.
Good DIY jobs
- Replacing a faucet aerator, showerhead or toilet flapper.
- Replacing a toilet supply line or fill valve.
- Clearing a sink trap or using a plunger.
- Replacing a leaking hose washer or spigot washer. See outdoor spigot leaking.
Jobs worth handing off
- Gas water heaters and gas lines: a mistake can cause a fire or carbon monoxide.
- Water heater replacement: venting, relief valve piping and expansion tanks all have rules. See expansion tanks.
- Sewer and slab work: digging, slope and code compliance.
- Anything inside a wall you can't see.
Before you sell
Work done without a required permit can come up during a home sale inspection. If you're planning to sell, it's worth doing it by the book.
Want it done right the first time? OX Plumbing is licensed in Arizona (ROC #347174) and answers 24/7.