Washington
King County, WA permit fees and requirements
King County prices a commercial building permit from two valuation tables — a plan review fee and an inspection fee
charged at application and at issuance — so a $1,200,000 project pays $11,918.00 for review and $18,903.00 for inspection, plus a $25.00 state surcharge, rather than one permit fee. Its plumbing permit is priced by the county's public health department at $137.00 plus $27.00 per fixture, and its electrical permit is not a county permit at all: it comes from the Washington State Department of Labor & Industries, which prices every job outside Seattle by amperage.
Permit costs we have worked out
Each page shows the fee components, the formula the jurisdiction uses, and a worked example you can follow by hand.
Estimate your potential King County permit fee with our Building Permit Fee Calculator.
| Permit | Category | Last reviewed |
|---|---|---|
| King County building permit cost | structural | 2026-09-24 |
| King County electrical permit cost | electrical | 2026-09-24 |
| King County plumbing permit cost | plumbing | 2026-09-24 |
Local context
What is specific to King County
Unincorporated King County is the first jurisdiction on this site whose three permits come from three different authorities, and that is a fact about the place rather than a filing convention. The Permitting Division prices building work, Public Health — Seattle & King County prices plumbing and gas piping, and the electrical permit is bought from the state. The county's own Guide 02 says so in its margin, and the three schedules it points to are written by three bodies that never sat down together.
The building fee is where the county differs most from every jurisdiction published before it. There is no single permit fee. The guide publishes a plan review table and an inspection table and applies the same County valuation to both, so a project pays each one: on $1,200,000 that is $11,918.00 at application and $18,903.00 at issuance. The county's own column headings are "Application" and "Permit", which is the clearest statement available that these are moments rather than alternatives. Both tables close at every seam — $788, $1,303, $1,988, $6,548, $10,548, $37,948 for review and $1,298, $2,068, $3,153, $9,993, $16,843, $58,043 for inspection — and this site asserts each one in its tests, because a split fee is exactly the shape in which a transcription error survives unnoticed.
What the fee is read against is also different. The county does not simply take the applicant's number: "The permit technician or plans examiner determines the County valuation... using data tables that list the standard construction cost per square foot, by type of construction and occupancy, or other data provided by the permit applicant." A declared construction cost is one acceptable input, not the whole answer, and a project can therefore be priced above what it cost. Denver and Westminster both take what you declare; King County may replace it.
Then there is the residential route, which uses neither table. Guide 02 prices single-family work by named job and by square foot — a basic new home is $1,936.00 of application review plus $2.46 per square foot of inspection, a deck or accessory building of 500 square feet or less is $772.00 of review, a mechanical installation alone is $183.00 of inspection. A homeowner and a commercial tenant in the same county are priced by arithmetic that shares nothing but the state surcharge, and the surcharge itself differs: $25.00 on the commercial guide's permits and $6.50 on the residential guide's, mirroring RCW 19.27.085's two rates.
The state's share does not stop at the surcharge. An electrical permit here is issued under WAC 296-46B-906, which prices work by amperage — a 200-ampere altered service is $109.90, a 400-ampere commercial altered service is $303.60 — and charges $8.20 for each circuit beyond the first four on a residential panel and beyond the first five on a commercial one, with a published ceiling: the cost of the alterations in a panel should not exceed the cost of a complete service of the same rating, which is the only place in this dataset where a schedule caps the sum rather than the line.
Valuation
How valuation is determined here
King County determines the valuation itself, from published cost data, and accepts the applicant's own figures as one input among others: "The permit technician or plans examiner determines the County valuation of the building construction or mechanical installation of a project, using data tables that list the standard construction cost per square foot, by type of construction and occupancy, or other data provided by the permit applicant. The County generally uses data tables published by nationally recognized code organizations but may use other means to estimate valuation as needed."
The pages here compute from the figure you give them and never substitute a rate for it. What they cannot tell you is whether the county would accept that figure, because the cost tables the county uses are published by code organizations rather than by the county.
Two routes do not use a valuation at all. Single-family work is priced by Guide 02's named rows and by square foot, and the plumbing permit is priced per fixture by the public health department's own schedule. Neither has a valuation to declare.
Who to contact
The office that issues the permit, with the details we have verified. Confirm current hours before travelling.
What these fees do not include
The list is not a disclaimer: on a new house the fees left out can outweigh the permit fee several times over. Every entry here is stated on the permit page as well.
Not included in our estimates
These figures are what King County's own published schedules say, computed by this site's engine. They are not a total project cost. In particular they exclude:
- The flat minimum fees for named structures, which sit above the valuation tables on Guide 04's own page: a building change of use at $970.00 application and $419.00 permit, a communication antenna at $3,364.00 and $1,514.00, a pole or tower at $6,272.00 and $4,280.00, a sign at $1,597.00 and $737.00, a school portable at $5,269.00 and $4,225.00, a trail bridge at $42.00 and $65.00 per lineal foot, and demolition or relocation at $796.00.
- Every accessory system and equipment row, including alarm systems at $1,160.00 plus $24 per device, sprinkler systems at $1,160.00 plus $24 per head, emergency generators and high-piled storage at $1,711.00 each, and tanks or underground fuel piping at $970.00 each.
- Guide 02's single-family rows, which price named residential jobs by job or by square foot: a new home at $1,936.00 to $8,128.00 of application review plus $2.46 per square foot of inspection, an accessory building over 500 square feet at $1,627.00 of review, a garage addition at $3,109.00, a remodel at $362.00 to $2,392.00 depending on how many structural modifications it makes, a fuel tank at $970.00, an exempt domestic well at $150.00 to $350.00, and site condition inspections at $726.00 per trip.
- Certificate of occupancy and operating permit fees: $442.00 for an individual townhouse, $970.00 for more than one building per permit, $970.00 for a temporary certificate, $419.00 per building per site visit for an occupancy inspection, $171.00 for an operating permit and $114.00 for its renewal, per item.
- Plan re-submittals after the second, and revisions to an issued permit, which the guide prices by how much of the project the changes represent rather than at a published figure.
- School impact mitigation fees, which are on a separate guide, and site, road, storm water and environmental review fees, which are on four more.
- The county's own hourly and hourly-equivalent charges in the plumbing program — plan review at $273.00 per hour, an inspection outside regular hours at $410.00 per hour, a requested site visit with no permit at $273.00, a permit renewal at $68.00 and an administrative fee at $41.00 — and, in the re-pipe note, a supplemental fee based on anticipated inspections.
- The state's other electrical charges: plan review at 35% of the permit fee and a $100.50 submission fee, progress inspections at $59.50 per half hour, after-hours inspections at $151.10, plan review handling at $27.90, annual permits from $2,913.90, and every trip fee.
- Anything charged by another authority for the same project: a site in an incorporated city is not in this county's territory, and a site in Seattle, Tacoma or Tacoma Power's service area is not in the state's electrical territory either.
Official sources for this jurisdiction
The documents these figures are transcribed from. Where a source contradicts itself we keep both readings and say so on the permit page.
- Fee schedule (PDF)CountyPrimary source
2026 Fee Guide 02 — Single Family Residential Construction (December 2025)
Three pages, sha256 beginning 2a1e0f0f0a2b4e5b. Read in three pdftotext modes. Two things are taken from it and nothing else. The first is the residential state surcharge of $6.50, which is a different figure from Guide 04's $25 and is the reason the surcharge is modelled as two rules rather than one. The second is its statement of which authority issues what — "Electrical permits are issued by the WA State Department of Labor & Industries. On-site septic design and installation, plumbing, and gas-piping permits are issued by Seattle-King County Public Health" — which is the corroboration for a jurisdiction having three permit types from three bodies. Its own fee rows are quoted in prose and not modelled; they are priced per square foot or per named job rather than by valuation.
- Fee schedule (PDF)CountyPrimary source
2026 Fee Guide 04 — Commercial or Multifamily Residential Building Construction (December 2025)
Three pages, dated "December 2025" in the footer and titled "2026 Fee Guide 04", sha256 beginning 72ef257d6aab25d1. Read 2026-09-24 in three pdftotext modes. This is the document behind every building figure published here: the two valuation tables on its last page, the state surcharge row and its WAC 51-05-200 footnote on its second, and the flat minimum-fee table on its first. The guide's own method paragraph is what makes the two tables a fee rather than two options — the County valuation "is then applied to the fee tables below to determine the required plan review and inspection fees".
- Fee schedule (PDF)CountyPrimary source
Plumbing and Gas Piping Program service fees (effective January 1, 2026)
A county document that prices City permits, which is why it is recorded against Seattle as well as against King County. SMC 22.900G.030 is the City's own instruction: "Fees for plumbing, medical or dental gas, lab gas, and fuel gas piping shall be collected by the Director of King County Public Health in accordance with the fee schedule as set forth in Seattle Municipal Code Section 504." The figures are $137.00 plus $27.00 per fixture. The same PDF appears in the King County payload under the same key, because it is the same document and the same fee.
- State agencyStatePrimary source
WAC 296-46B-906 — Electrical inspection fees (Washington State Legislature)
The complete fee schedule for electrical work in every part of Washington outside Seattle, Tacoma and Tacoma Power's service area, published by the Legislature as a regulation rather than as a municipal document. Read 2026-09-24 from the official citation. The section states its own method in one sentence — "To calculate inspection fees, the amperage is based on the conductor ampacity or the overcurrent device rating" — which is why every rule taken from it is banded by amperage. Its most recent filing is WSR 26-10-060, effective July 1, 2026; no effective date is asserted for the version read here, because the citation page does not date the text it serves.