State licensing boards · verified July 2026
Plumber license reciprocity, state by state
The short answer
As of July 2026, 10 states publish formal reciprocity agreements for plumbers. California publishes the widest list, accepting licenses from 5 other states. Reciprocity is never automatic: receiving states generally require that the original license was earned by examination, remains in good standing, and in many cases has been held for a minimum period.
Which states accept licenses from where?
Each row below is a state that publishes an agreement list, and the states it names. Read it as "this state will consider an application from a license holder in these states", not as a guarantee of recognition.
| State | Accepts from | States named |
|---|---|---|
| Alabama | 1 | Mississippi |
| California | 5 | Arizona, Louisiana, Mississippi, Nevada, North Carolina |
| Delaware | 3 | CT, IA, MD |
| Iowa | 1 | SD |
| Louisiana | 2 | AR, TX |
| Montana | 4 | Idaho, North Dakota, Oregon, South Dakota |
| North Dakota | 3 | Minnesota, Montana, South Dakota |
| Oklahoma | 1 | Arkansas |
| Oregon | 2 | Idaho, Montana |
| Washington | 1 | ID |
Source: each state's own licensing board. Verified July 2026.
Which license travels farthest?
Looked at the other way round, some state licenses are named in more agreements than others. 4 states tie at the top, each named in 2 agreements. These are the licenses most widely accepted elsewhere for this trade:
- Idaho: accepted by 2 states (Montana, Oregon)
- Mississippi: accepted by 2 states (Alabama, California)
- Montana: accepted by 2 states (North Dakota, Oregon)
- South Dakota: accepted by 2 states (Montana, North Dakota)
- AR: accepted by 1 state (Louisiana)
- Arizona: accepted by 1 state (California)
- Arkansas: accepted by 1 state (Oklahoma)
- CT: accepted by 1 state (Delaware)
- IA: accepted by 1 state (Delaware)
- ID: accepted by 1 state (Washington)
- Louisiana: accepted by 1 state (California)
- MD: accepted by 1 state (Delaware)
- Minnesota: accepted by 1 state (North Dakota)
- Nevada: accepted by 1 state (California)
- North Carolina: accepted by 1 state (California)
- North Dakota: accepted by 1 state (Montana)
- Oregon: accepted by 1 state (Montana)
- SD: accepted by 1 state (Iowa)
- TX: accepted by 1 state (Louisiana)
If you expect to move, this is worth knowing before you choose where to get licensed. It is also worth checking the hour requirement in both states, because a license earned under a lower requirement is sometimes the one a receiving state declines to accept.
What conditions apply?
Reciprocity agreements are conditional rather than automatic, and the conditions repeat across states. The original license generally has to have been earned by passing an examination rather than granted under a grandfathering provision. It usually has to be current and in good standing. Many states add a minimum holding period, commonly one year. Some require the receiving state's own business and law examination even when they waive the trade exam. Fees apply either way.
What if there is no agreement?
You apply as a new candidate and sit that state's examination. Experience earned elsewhere usually still counts toward the hour requirement, which is the part people miss: an electrician with eight years in a non-reciprocal state normally does not start over on hours, only on the exam. Check how the receiving state documents out-of-state experience, because that is where applications stall.
Sources and verification
How this was compiled
Every agreement above comes from the publishing state's own board page or rules, linked in the table. Where a state's rules allow reciprocity but publish no list of partner states, no agreement is asserted here. That conservative treatment is why some states you might expect are absent.
Last verified July 2026 · Found an error? Report it and it will be corrected and logged on the corrections page.
Compare requirements with the hours by state table, or see plumbers pay and outlook.
Agreements change and conditions differ by state. This page is informational only, so confirm with the board you are applying to before relying on it. Not legal advice.