Licensed Plumbing Contractors in Washington
Every plumbing contractor license on file with the Washington State Department of Labor & Industries, licensed by L&I for plumbing work. Status recomputed daily. Last updated August 17, 2026.
843 of 3,029 plumbing contractors in Washington (27.8%) currently hold an expired license. That is not a rounding error, it is roughly one in 4 of everyone in the trade. Licenses lapse quietly, and nothing stops an expired licensee from answering the phone and quoting your job.
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What a plumbing contractor license does and does not tell you
A current license means the L&I has confirmed this person met the state's competency and examination requirements and has kept the registration paid up. It does not mean they carry liability insurance, that their work is warrantied, or that previous customers were happy. Verify the license here, then ask for a certificate of insurance and references separately.