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How to get a plumber license in Washington

Requirements, license levels, and the issuing authority — sourced from Washington's official board.

Certificate types and 8,000-hour requirement confirmed on the official L&I page; exact renewal-term length and CE detail come from L&I renewal guidance rather than the fetched certification page.

Issuing authority: Washington State Department of Labor & Industries (L&I). Official page: https://lni.wa.gov/licensing-permits/plumbing/plumber-certification/

License levels in Washington

Washington plumber licensing at a glance

RequirementsJourney level: 4+ years (at least 8,000 hours) as a plumber trainee under a certified journey-level plumber, of which at least 2 years (4,000 hours) must be in commercial or industrial installations; pass the 3-part journey exam (70%).
ReciprocityReciprocal certification with Idaho for journey-level plumbers (Idaho journey-level license waives the trade portion of the WA exam); other states/military may be considered.
RenewalRenewal requires approximately 8 hours of approved continuing education (per L&I renewal guidance).
NotesCertificate types and 8,000-hour requirement confirmed on the official L&I page; exact renewal-term length and CE detail come from L&I renewal guidance rather than the fetched certification page.

Questions

Do you need a license to work as a plumber in Washington?
Certificate types and 8,000-hour requirement confirmed on the official L&I page; exact renewal-term length and CE detail come from L&I renewal guidance rather than the fetched certification page.
What plumber license levels does Washington have?
The levels are Journey Level Plumber (PL01), Residential (PL02), Pump & Irrigation (PL03), Domestic Well (PL03A), Residential Service (PL04), Medical Gas Piping Installer (MG01), Backflow (PL30), Plumber Trainee (registration).
How do you get licensed as a plumber in Washington?
Journey level: 4+ years (at least 8,000 hours) as a plumber trainee under a certified journey-level plumber, of which at least 2 years (4,000 hours) must be in commercial or industrial installations; pass the 3-part journey exam (70%).
Does Washington have plumber license reciprocity?
Reciprocal certification with Idaho for journey-level plumbers (Idaho journey-level license waives the trade portion of the WA exam); other states/military may be considered.

Related

Supply
How many plumbers in WashingtonHub
All Washington trades pages

Sources: lni.wa.gov. Always confirm current requirements with the issuing authority.

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