How to Become a Plumber in Washington
In Washington, a Plumber license typically requires a state exam, a 70% passing score, and a $202.1 exam fee.
Installs and repairs water, gas and drainage systems. Journeyman plumber licenses vary by state and locality; many require apprenticeship hours plus an exam. Requirements change — always confirm with Washington State Department of Labor & Industries (L&I) — Plumber Certification Program before paying.
Licensing steps in Washington
- 1Meet the basic requirements
Minimum age 18.
- 2Complete pre-license education
Required training hours are not published here — check with the state board for the current figure.
- 3Register and pass the exam
The exam is administered by PSI; you need 70% to pass.
- 4Pay fees and get licensed
Exam fee $202.1 · license $242.7
- 5Stay current
License renews every 2 years with 16 hours of continuing education.
Plumber requirements — Washington at a glance
| Education hours | — |
| Exam vendor | PSI |
| Questions (national/state) | — / — |
| Passing score | 70% |
| Exam fee | $202.1 |
| Application fee | — |
| License fee | $242.7 |
| First-attempt pass rate | not published |
| Retake rule | — |
| Renewal | every 2 years · 16 CE |
| Reciprocity | Yes — Idaho only, for journey level plumbers (bilateral) |
Official source: Washington State Department of Labor & Industries (L&I) — Plumber Certification Program ↗
Frequently asked questions
How long does it take to get a Plumber license in Washington?
After completing the required education, most candidates need 4-12 weeks of study before the exam. Total timeline depends on scheduling.
How hard is the Plumber exam in Washington?
Official first-attempt pass rates are not published by Washington; check the state board.
What does the Plumber license cost in Washington?
The exam fee is $202.1, and the license fee is $242.7
Can I transfer my Plumber license to Washington?
Reciprocity: Yes — Idaho only, for journey level plumbers (bilateral).
Plan your Plumber licensing in Washington
This guide is informational and not legal advice. Requirements change frequently — verify all figures with Washington State Department of Labor & Industries (L&I) — Plumber Certification Program (retrieved 2026-08-20).