Do I need a plumbing permit in Washington?

In most of Washington, yes. Permits are issued locally, so the answer comes from your Washington city or county rather than a single statewide rule. Of the 8 Washington jurisdictions we have verified for plumbing work, 7 require a permit outright, 1 depends on the size or scope of the job, and 0 require none.

Is there a plumbing permit exemption in Washington?

1 of the 8 Washington jurisdictions we cover sets a threshold rather than a flat rule, so the same job can be exempt in one Washington county and permitted in the next. The table above lists each Washington jurisdiction's published threshold in its own words, with the source and the date we verified it.

Washington

Do you need a plumbing permit in Washington?

By Mario Bailey Last checked 19 Jul 2026

Always required: 7; of 8 jurisdictions
Conditional: 1; depends on size or scope
Not required: 0; exempt outright

Plumbing Permit rules nationwide, beyond Washington.

A plumber tightens a fitting on water supply pipes

Requirements and size thresholds for plumbing permits vary by locality. The table below compares what each Washington county or city requires. Always confirm with the local office before starting.

Comparing states? See plumbing permit rules across every locality we cover.

The application steps and inspection sequence for plumbing permits come from the model code rather than from Washington law, so they read the same wherever you build. We keep that walkthrough in one place: how a plumbing permit application and its inspections work, start to finish. What changes between Washington jurisdictions is below: who requires a permit, what they charge, and which office you file with.

Swipe sideways to see thresholds and confidence.

Locality	Permit required?	Typical threshold	Confidence
Bellevue	Conditional	permit required for new plumbing, concealed piping, and fixture additions; replacing a sink toilet or faucet not concealed in a wall does not require a permit	Confirmed on official page
Clark County	Yes	A plumbing permit is required for installation of any plumbing fixtures, including water heaters, toilets and sinks.	Confirmed on official page
King County	Yes	Not specified	Confirmed on official page
Pierce County	Yes	Not specified	Confirmed on official page
Seattle	Yes	Not specified	Confirmed on official page
Snohomish County	Yes	Not specified	Confirmed on official page
Tacoma	Yes	Not specified	Confirmed on official page
Thurston County	Yes	No permit is needed only to clear a blockage or to repair or stop a leak in a drain, water, soil, or vent pipe.	Confirmed on official page
No localities match your filter.

What a plumbing permit costs in Washington

6 Washington jurisdictions we cover publish a fee figure for this work. Each line is quoted from that office's own schedule and linked to its citation. The figures are not comparable to one another: some are flat minimums, some a percentage of job value, some charged per fixture, so what you pay depends on which schedule applies and on your job's valuation.

Bellevue

Plumbing permit fee per Table 11 of Ordinance 6879, $50 for the first fixture plus $17.34 for each additional fixture, plus separate piping fees starting at $46 for pipe up to 1 inch, effective 2026-01-01

last checked 18 Jun 2026

Clark County

Application rev 9.2.25: $94 issuance plus per-item fees including plumbing fixture/trap 1-5 $192, water heater $29, lawn sprinkler $122; homeowner water heater only permit $66 with no issuance fee.

last checked 19 Jul 2026

King County

Issued by Public Health Seattle and King County rather than the county Permitting Division; the plumbing and backflow permit fee is $137 plus $27 per fixture, effective 1/1/2026

last checked 18 Jun 2026

Pierce County

Issue each plumbing permit fee $58.00, plus unit fees per fixture (for example $8.00 per fixture on one trap, $8.00 for a water heater and/or vent) (PCC Table 17C.10-1-D, 2026 fees).

last checked 6 Jul 2026

Snohomish County

Filed as a Mech/Plbg residential trade permit priced from the PDS valuation table starting at a $45 permit fee plus $29.25 plan check at the lowest valuation bracket, plus a $150 base fee per application, the $6.50 state surcharge and a 3% technology surcharge, per PDS Bulletin 18 effective 3/13/2026; new-construction plumbing adds 11% to the permit fee instead of per-fixture charges

last checked 6 Jul 2026

Tacoma

Standalone plumbing permits run 2.81 percent of construction value with a $180 minimum fee, per the PDS Fee Schedule effective 1/1/2025

last checked 18 Jun 2026

Jurisdictions not listed publish no dollar figure we could quote. Absence does not mean a permit is free.

Common questions about plumbing permits in Washington

Do I need a plumbing permit in Washington?: In most of Washington, yes. Permits are issued locally, so the answer comes from your Washington city or county rather than a single statewide rule. Of the 8 Washington jurisdictions we have verified for plumbing work, 7 require a permit outright, 1 depends on the size or scope of the job, and 0 require none.
Is there a plumbing permit exemption in Washington?: 1 of the 8 Washington jurisdictions we cover sets a threshold rather than a flat rule, so the same job can be exempt in one Washington county and permitted in the next. The table above lists each Washington jurisdiction's published threshold in its own words, with the source and the date we verified it.

Do you need a plumbing permit in Washington?

What a plumbing permit costs in Washington

Common questions about plumbing permits in Washington

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