Seattle, Washington Building Permit Guide

Seattle is the largest permitting jurisdiction in Washington and one of the few cities in the state that runs its own electrical programme rather than leaving electrical to Labor and Industries. It publishes its own Seattle Building, Residential, Electrical, Energy, Mechanical and Grading Codes, all sitting on top of the state minimum.

SDCI issues land use, construction and trade permits, approves more than 55,000 permits a year and performs roughly 240,000 on-site inspections (2026 city budget). Because the city holds the electrical programme itself, a Seattle project is one of the few in Washington where the electrical permit and the building permit come from the same department.

This guide covers work inside the Seattle city limits. Unincorporated King County is permitted by the county, and the other King County cities each administer the state code themselves.

What requires a building permit in Seattle?

Seattle enforces the state code through its own Seattle Department of Construction and Inspections, and amends it extensively into what the city publishes as the Seattle Building Code. That does not put Seattle outside the state system: the codes enumerated in chapter 19.27 RCW, the State Building Code Act, are required in all cities and counties, and a city’s amendments sit on top of the state minimum rather than in place of it. What is genuinely different here is the depth of the local amendments and the fact that the city runs its own electrical programme rather than leaving electrical to the state. Seattle front-loads its review rather than discovering problems late. A Pre-Application Site Visit produces a report identifying environmentally critical areas, drainage patterns, trees, existing structures, the street curb and potential property line impacts, with a target of five business days; on most land use and new construction applications a Preliminary Assessment then runs across SDCI, the transportation department, public utilities and the city light utility specifically to identify major project stoppers before the main review begins

An ordinary repair is defined more narrowly than owners expect, and an exemption from a building permit is never an exemption from zoning, critical areas review, the energy code or a trade permit. Confirm scope with SDCI before work starts.

The layers that sit on top of the state minimum

Because the city amends the state code and administers the result itself, several local layers routinely catch projects owners assume are simple: the city’s own energy and land use provisions, design review in defined areas, tree and critical areas regulation, and its own electrical permitting. State amendments still govern underneath all of it, so the question is never simply which model code applies — it is the model code, plus the state amendments, plus the city amendments, in that order.

Who handles permitting in Seattle?

SDCI administers the city ordinances regulating building construction, land use and housing, issuing land use, construction and trade permits and running construction and housing inspections alongside the city’s rental registration and inspection programme.

The list of codes SDCI enforces is unusually long, and each is a separate compliance track: the Seattle Building and Residential Codes, the Seattle Electrical Code, the Seattle Energy Code, the Seattle Mechanical Code, the Seattle Grading Code, the Environmentally Critical Areas Ordinance, the Tree Protection Ordinance, the Stormwater and Side Sewer Codes, the Shoreline Master Programme and the State Environmental Policy Act.

Trees are a live constraint on ordinary residential work. Development applications must identify every existing tree over 6 inches in diameter on the site plan, including location, size and species, and exceptional trees must be retained except where doing so would prevent a project from meeting its development potential. Tree work also runs through the city’s tree service provider registry.

In 2025, building permits issued in Seattle authorized 4,366 new privately owned housing units, 468 of them single-family homes, according to the U.S. Census Bureau Building Permits Survey.

Permit types

Residential permits

Residential work follows the Seattle Residential Code with the city’s land use code applied alongside. The $6,000 minor-work exemption is the first question, and the carve-outs for load-bearing supports, envelope changes and anything reducing egress, light, ventilation or fire resistance are the second. Even exempt work must still meet all code requirements and development standards.

How Washington contractor credentials work

Commercial permits

Commercial and land use work runs through the Master Use Permit process, with design review and environmental policy review attaching on larger projects and adding materially to the calendar. The Preliminary Assessment is the mechanism for finding project stoppers early, and it is worth paying for on any project where the site conditions are not already well understood.

Registrations, trade certifications and design professionals

Three credential layers appear on Washington projects: the state contractor registration under chapter 18.27 RCW, which nearly everyone doing the work needs; separate state trade certification for electricians and plumbers, each examined and administered by its own programme; and, on commercial and larger residential work, drawings stamped by a Washington-licensed architect or professional engineer. Confirm what SDCI requires for the specific building before filing.

Most Washington contractors register with the Department of Labor and Industries (with a surety bond and insurance) rather than holding a licence; electrical and plumbing contractors also need an L&I contractor licence. Contractor licensing in Washington

Seattle permit costs and fees

Seattle fees follow the SDCI fee schedule, with mandatory housing affordability payments attaching to qualifying projects and pre-application site visit fees credited against future fees where the city determines a visit was not required.

Washington sets the code statewide but leaves the fee schedule local, so two jurisdictions on the same edition can price the same project very differently. The electrical fee is the one that most often surprises people, because it is a separate city permit with its own fee. Ask SDCI for the schedule in force on your filing date, and confirm the electrical route separately.

Fees are set locally, plus a small state permit fee (RCW 19.27.085); the electrical fee goes to whichever body issues the electrical permit. Permit fees in Washington

Trade permits and who may pull them

Trade permits are separate from the building permit and, in Washington, are not all issued by the same body. Plumbing and mechanical permits come from the local jurisdiction under the codes the state has adopted. Electrical permits come from the city’s own electrical programme. That split is the single most common source of confusion on a Washington project.

Plumbing and mechanical permits are local; electrical permits come from the Department of Labor and Industries unless the city runs its own electrical programme or Tacoma Power serves the site. Trade permits in Washington

How to apply for a Seattle building permit

Review, corrections and what actually causes delay

In Washington the first cause of delay is the energy code, because the state code is its own instrument and more demanding than the international one most designers default to. After that comes critical areas review, which reaches ordinary residential work near wetlands, streams, steep slopes and shorelines and adds its own study and mitigation timeline. Then edition confusion around the switch-over date, when a new state edition takes effect and local amendments change with it. Build review time into the schedule and confirm the checklist with SDCI before filing.

The state code sets a 180-day default for permit validity, but Seattle may change it, so confirm the expiry on phased or delayed work. Permit validity in Washington

Inspections in Seattle

Where a permit is required, standard checkpoints include footing and foundation, framing, rough-in plumbing and mechanical, insulation and energy code compliance, fire systems on commercial work, and final, with a certificate of occupancy before the building is used. Because Seattle holds the electrical programme itself, the two inspection queues that split most Washington projects are unified here — which is a real advantage over the rest of the state.

The city issues its own electrical permits, so electrical inspections are requested from the city rather than from the state.

Do not cover work before the required inspection has been approved. Keep the issued permits — plural — the approved plans and the energy code documentation available on site.

Seattle permit search and official resources

Permit records in Washington are split the same way the permits are. Where SDCI is the authority for the City of Seattle, it holds the building and mechanical records — plumbing and gas-piping permits come from Public Health – Seattle & King County, and it holds the electrical record too, because the city issues its own electrical permits. If you are buying, refinancing or renovating, check both, because a clean local record does not mean the electrical work was ever permitted.

These are the primary sources behind this guide. Codes, fee schedules and procedures change — confirm the position for your filing date.

• SDCI, how do you get a permit
• SDCI, do you need a permit
• SDCI electrical permit
• Washington State Building Code Council
• Chapter 19.27 RCW, the State Building Code Act

Frequently asked questions

Do I need a permit for a small repair?

Not if it costs $6,000 or less in any six-month period, measured on the fair market value of labour and parts even if you do the work yourself. But a permit is required for any work on load-bearing supports, any change to the building envelope, and any work reducing egress, light, ventilation or fire resistance, no matter how small.

Who issues my electrical permit in Seattle?

SDCI does, under the Seattle Electrical Code. Seattle is one of the few Washington jurisdictions running its own electrical programme, so unlike most of the state the electrical permit and the building permit come from the same department. Most Washington contractors register rather than hold a licence; electrical and plumbing contractors must also hold an L&I contractor licence. Under chapter 18.27 RCW a contractor registers with the Department of Labor and Industries, files a continuous surety bond of $30,000 as a general contractor or $15,000 as a specialty contractor, and keeps liability insurance on file, renewing every two years. Registration is not a competence test and does not authorise trade work: electrical certification comes under chapter 19.28 RCW and plumbing under chapter 18.106 RCW. The electrical permit comes from the city, which runs its own electrical permits and inspections; elsewhere in Washington the Electrical Program at the Department of Labor and Industries (L&I) usually issues them.

Which code edition applies?

The Seattle amendments sit on top of the state minimum. Washington has a mandatory statewide building code. The codes enumerated in chapter 19.27 RCW, the State Building Code Act, are adopted and amended by the State Building Code Council within the Department of Enterprise Services and are required in all cities and counties, so local government administers and enforces them rather than choosing whether to have them. The 2021 editions took effect on the fifteenth of March, 2024 after two delays, and the 2024 editions are dated to take effect on the third of May, 2027. The state adopts a new edition every three years and reviews the codes in two groups, but all of them take effect on the same date (the 2021 codes on 15 March 2024, the 2024 codes on 3 May 2027). A city or county may make the state code stricter but cannot opt out of it; local changes affecting houses or apartments need State Building Code Council approval, and the residential energy code cannot be changed locally.

What is a Pre-Application Site Visit?

A site visit producing a report that identifies site conditions including environmentally critical areas, drainage patterns, trees, existing structures, the street curb and potential property line impacts. SDCI targets five business days. Where the city determines a visit was not required, paid fees are credited or refunded.

Do I need to survey my trees?

Development applications must identify all existing trees over 6 inches in diameter on the site plan, including location, size and species, and exceptional trees must be retained except where retention would prevent a project meeting its development potential.

Is exempt work really unregulated?

No. Even where no permit is needed, the project must still meet all code requirements and development standards. The exemption removes the permit, not the code.

Simplify Seattle permitting with Alliance Permitting

Seattle rewards front-loading, because the city has built the front-loading into its own process. We use it rather than discovering stoppers in review.

Trusted by leading builders, developers, and national contractors — 21+ years of filing in the jurisdictions we write about.

Contractors and builders choose Alliance for Seattle because the work is done by people who have stood at the counter:

• 21+ years of filing, so the edition and the electrical route are settled before submission
• We confirm which state code group governs each part of the work on your filing date
• State contractor registration, bond and insurance verified as active before filing
• Energy code and critical areas documentation prepared rather than discovered in review
• Two inspection queues sequenced so a cover-up never waits on the wrong inspector

Alliance Permitting is a permit documentation and submission company in Washington. We prepare your paperwork, file it correctly and coordinate with the permitting authority through issuance. We are not a contractor and we do not perform licensed plan review or inspections; that work stays with your licensed team and the jurisdiction.

This guide is provided by Alliance Permitting for general information about Seattle permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.