How do I check a plumbing license in Washington?

The Washington State Department of Labor and Industries (L&I), Plumbing Program keeps the record for plumbing contractors in Washington. Use the official lookup on this page, and treat the board's own record as final.

How much does a plumbing license cost in Washington?

$148.10 (Plumbing contractor license, each issuance, renewal or reregistration (WAC effective 7/1/26)). $53.20 (Initial identification or change of designated plumber). $202.10 (Plumber exam application (department fee; the exam vendor fee is extra)). $202.10 (Plumber reciprocity application). $242.70 (Journey level, residential or residential service plumber certificate renewal, three year). $60 (Plumber trainee certificate, one year).

How much experience do you need for a plumbing license in Washington?

Journey level plumber: four years, at least 8,000 hours, as a trainee under a certified journey level plumber.

How often does a plumbing license renew in Washington?

Plumbing contractor license expires 24 months after issuance (plumber certificates renew every three years).

How to get a plumbing license in Washington

Edited by John Voll. Last verified October 6, 2026.

Washington State Department of Labor and Industries (L&I), Plumbing Program licenses plumbing contractors in Washington. The L&I Contractor License Data: General, Washington State Department of Labor and Industries lists 2,212 active plumbing business records as of October 6, 2026.

Who licenses plumbing work in Washington

Credential	State license
Board	Washington State Department of Labor and Industries (L&I), Plumbing Program official statement
Official lookup	Search plumbing licenses
License types	Plumbing Contractor, Plumber certificates

How to get licensed

Apply to L&I as a Plumbing Contractor or Plumber certificates.
Board page
Yes. The plumbing contractor must employ a full-time certified plumber, and plumber certificates are issued only after passing the exam. source
Experience: journey level plumber: four years, at least 8,000 hours, as a trainee under a certified journey level plumber. source
Post a plumbing contractor surety bond of $6,000. source
Carry liability insurance: $50,000 property damage, $100,000 per person, $200,000 for more than one person. source
Pay the plumbing contractor license, each issuance, renewal or reregistration (WAC effective 7/1/26): $148.10. source
Plumbing contractor license expires 24 months after issuance (plumber certificates renew every three years). source

Plumbing requirements in Washington

Plumbing: exam, experience, bond, insurance, renewal and feesSources checked October 6, 2026
Exam	Yes. The plumbing contractor must employ a full-time certified plumber, and plumber certificates are issued only after passing the exam. source
Experience	Journey level plumber: four years, at least 8,000 hours, as a trainee under a certified journey level plumber. source
Bond	Plumbing contractor surety bond of $6,000. source
Insurance	Liability insurance: $50,000 property damage, $100,000 per person, $200,000 for more than one person. source
Renewal	Plumbing contractor license expires 24 months after issuance (plumber certificates renew every three years). source
Reciprocity	Yes, for journey level plumbers from Idaho; RCW 18.106.155 allows reciprocity with substantially equivalent states that return the privilege. source
Fees	$148.10 (Plumbing contractor license, each issuance, renewal or reregistration (WAC effective 7/1/26)). source $53.20 (Initial identification or change of designated plumber). source $202.10 (Plumber exam application (department fee; the exam vendor fee is extra)). source $202.10 (Plumber reciprocity application). source $242.70 (Journey level, residential or residential service plumber certificate renewal, three year). source $60 (Plumber trainee certificate, one year). source

Hiring a plumbing contractor?

See every official lookup in Washington, which board covers which trade, and what to check before you hire.

How to verify a contractor license in Washington

Questions

Do you need a plumbing license in Washington?: Washington State Department of Labor and Industries (L&I), Plumbing Program licenses plumbing contractors in Washington.
How do I check a plumbing license in Washington?: The Washington State Department of Labor and Industries (L&I), Plumbing Program keeps the record for plumbing contractors in Washington. Use the official lookup on this page, and treat the board's own record as final.
How much does a plumbing license cost in Washington?: $148.10 (Plumbing contractor license, each issuance, renewal or reregistration (WAC effective 7/1/26)). $53.20 (Initial identification or change of designated plumber). $202.10 (Plumber exam application (department fee; the exam vendor fee is extra)). $202.10 (Plumber reciprocity application). $242.70 (Journey level, residential or residential service plumber certificate renewal, three year). $60 (Plumber trainee certificate, one year).
How much experience do you need for a plumbing license in Washington?: Journey level plumber: four years, at least 8,000 hours, as a trainee under a certified journey level plumber.
How often does a plumbing license renew in Washington?: Plumbing contractor license expires 24 months after issuance (plumber certificates renew every three years).

Other trades in Washington

Plumbing license in other states

Sources

This is not a government site. The licensing board's own record governs; always confirm on the official lookup. Information as of October 6, 2026.