Mukilteo issues its own building, mechanical, plumbing, fire and engineering permits through the Permit Center of the Planning and Community Development Department, and every application goes in through the City’s SmartGov online permit center. Wiring permits and inspections belong to the state Department of Labor and Industries (L&I), with an office in south Everett. Under the master fee schedule in force since April 10, 2026, a valuation-based building permit starts at $135 and plan review adds 75% of the permit fee.
The Permit Center is in City Hall at 11930 Cyrus Way. The counter is staffed Monday to Thursday from 8 a.m. to noon and 1 to 5 p.m.; City Hall is closed on Fridays. The Census estimate for 2025 puts Mukilteo at 21,239 residents.
Mukilteo permits cover land inside the city limits. Snohomish County issues permits on unincorporated land outside them.
What requires a building permit in Mukilteo?
Section 15.04.040 of the Mukilteo Municipal Code (MMC) sets the City’s own list of work that needs no building permit; everything else that the adopted codes cover needs one. Exempt work must still meet the codes and can still need a land use, shoreline, critical areas or tree approval.
Permit required
- New homes, accessory dwelling units, additions and structural alterations, and any wall removal in a kitchen remodel
- Every re-roof, overlays included, and every new window (the City’s homeowner page)
- Water heater replacement (plumbing permit) and furnace, heat pump or air conditioner replacement (mechanical permit)
- Detached accessory buildings over 200 sq ft, or any heated one
- Decks over 200 sq ft or more than 30 inches above grade at any point, and any change to deck stairs or handrails
- Demolition, signs, swimming pools and temporary structures
- Retaining walls over 4 feet or carrying a load (an engineering permit)
No building permit (MMC 15.04.040)
- One-story, unheated residential accessory structures of 200 sq ft or less, with walls no taller than 8 feet and eaves no deeper than 24 inches (120 sq ft for commercial sites)
- Uncovered residential decks of 200 sq ft or less that are no more than 30 inches above grade and not over a basement or story below
- Fences up to 7 feet with no masonry or concrete above 6 feet
- Sidewalks and driveways, playground equipment, and window awnings that project 54 inches or less
- Above-ground pools under 24 inches deep holding 5,000 gallons or less
- Painting, papering, tiling, carpet, cabinets and counter tops
Two rules on the City’s homeowner page are zoning limits rather than building code: a fence over 6 feet (or over 4 feet inside the front setback) needs a fence modification, which caps residential fences at 8 feet, and a shed of any size must meet the setbacks in MMC chapter 17.20. The code exemption list is the adopted one where the two differ.
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Get a free quote →What the city decides and what the state holds
The technical codes come from the State Building Code Council: MMC 15.04.020 (Ordinance 1493 of 2024) adopts the 2021 International Building, Residential, Mechanical, Fuel Gas, Existing Building, Swimming Pool and Spa and Wildland-Urban Interface codes, the Uniform Plumbing Code and the Washington State Energy Code. Mukilteo adds the radon, tiny house and dwelling sprinkler appendices of the residential code, the shorter exemption list above, 80% refunds on mechanical and plumbing fees, and fees set by Council resolution.
Washington has a mandatory statewide building code under chapter 19.27 RCW that every city and county enforces and may make stricter; electrical permits come from the Department of Labor and Industries unless the city runs its own program or Tacoma Power serves the site. Building codes in Washington
Mukilteo building department: who handles permitting
The Planning and Community Development Department runs the Permit Center. Its Building Official reviews plans and inspects construction, planners handle zoning, critical areas, shoreline and tree rules, and the City’s engineering staff review clearing, grading, stormwater and right-of-way work.
| Detail | Information |
|---|---|
| Office | Permit Center, Mukilteo City Hall, 11930 Cyrus Way, Mukilteo, WA 98275 |
| Phone | 425-263-8000 (inspection line: extension 7) |
| permitcenter@mukilteowa.gov (portal help), buildingdept@mukilteowa.gov (building questions), planningdept@mukilteowa.gov (zoning) | |
| Counter hours | Monday to Thursday, 8 a.m. to noon and 1 to 5 p.m.; City Hall is closed on Fridays |
| Applications, payments, inspections | SmartGov online permit center |
| Electrical permits | Washington Department of Labor and Industries |
| Septic, wells | Snohomish Health District |
The City warns that scam emails dressed up as permit invoices are circulating: Mukilteo takes payment only through its portal or in person at City Hall and never sends invoices by email.
Permit types
Residential permits
The residential checklist sets what goes in with each job. A new house or detached ADU needs a site plan, code summary, foundation, floor and roof plans, a wall envelope detail, elevations, energy documents, the City’s building height worksheet, a water availability letter and any structural calculations. An addition drops the water letter; an interior alteration needs floor and work area plans; a deck needs a site plan, footing and framing plans and a cross section.
A new single-family home or duplex also needs a separate engineering permit, and so does an ADU that connects downspouts to the City’s storm system, adds 2,000 sq ft or more of hard surface, or clears or grades 1,000 sq ft or more. Flat 2026 fees cover the common small jobs: a single-family re-roof is $159.19 and a residential demolition $220.81, each plus the state fee, and a demolition application needs a hazardous materials report.
Building or remodeling a home here? Alliance handles residential permit expediting, so the crew isn't waiting on the counter.
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Get a free quote →Commercial permits
Commercial and multifamily work uses the commercial building checklist and the same valuation table, with plan review at 75% and separate mechanical and plumbing permits; the combined mechanical-plumbing permit is only for single-family work. Fire alarm and sprinkler permits start at $215.67, plus $6.16 per sprinkler head or new alarm device, and carry their own 75% plan review. A commercial re-roof is $215.67.
For tenant improvements and new commercial builds, Alliance handles commercial permit applications through issuance. More on this: commercial building permits explained.
What comes before the building permit
Planning reviews come first where they apply. The City Council rewrote the critical areas rules on March 23, 2026 (Ordinance 1533), and until the online code catches up the City posts the new text at the top of the portal’s document library. Waterfront lots fall under the Shoreline Management title of the code (MMC 17B): a shoreline exemption costs $667.55 and a substantial development permit $4,272.32. Building in a mapped flood zone needs a floodplain development permit ($427.23, or $747.66 for substantial development), an elevation certificate, and, in a V (coastal high hazard) zone, the City’s V-zone design certificate.
Other early steps: a minor site plan review for a house ($256.75), an ADU review ($774.36), SEPA review where it is not exempt ($907.87), and a tree permit to remove any tree in a critical area or native growth protection area, or, elsewhere, an evergreen of 8 inches or more (deciduous 12 inches) in diameter at breast height. Water and sewer come from the Mukilteo Water and Wastewater District or the Alderwood Water and Wastewater District depending on the lot, and septic systems and wells are permitted by the Snohomish Health District.
Mukilteo permit costs and fees
Building fees come from the 2026 Master Fee Schedule adopted by Resolution No. 2026-03, in effect since April 10, 2026. Valuation is the square footage times the current ICC building valuation data with the regional modifier; a “good construction” house (for example over 5,000 sq ft or three stories) is valued 30% higher. The plan review fee is due when you apply and the permit fee when the permit is issued, and the dollar amounts rise each January 1 by the June-to-June Seattle-area CPI-W unless the Council decides otherwise.
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Call 1-855-478-4290 →| Item | Fee or rule |
|---|---|
| Valuation up to $2,000 | $135 |
| $2,000.01 to $25,000 | $135 for the first $2,000, plus $18.50 per added $1,000 or part |
| $25,000.01 to $50,000 | $495 for the first $25,000, plus $14.50 per added $1,000 or part |
| $50,000.01 to $100,000 | $866.25 for the first $50,000, plus $10.50 per added $1,000 or part |
| $100,000.01 to $500,000 | $1,388.75 for the first $100,000, plus $8.50 per added $1,000 or part |
| $500,000.01 to $1,000,000 | $4,688.75 for the first $500,000, plus $7.50 per added $1,000 or part |
| $1,000,000.01 to $3,000,000 | $8,263.75 for the first $1,000,000, plus $6.00 per added $1,000 or part |
| Over $3,000,000 | $23,263.75 for the first $3,000,000, plus $3.50 per added $1,000 or part |
| Plan review | 75% of the permit fee; added plan review billed hourly, 1-hour minimum |
| State Building Code Council fee | Single-family, duplexes and townhomes $6.50, plus $2.00 per residential unit over one; multifamily and commercial $25.00, plus $2.00 per residential unit over one |
| Technology fee | 3% of the required permit fees |
| Plumbing or mechanical permit | $138.65 issuance plus $15.41 per fixture; heat pumps $0 |
| Re-inspections | $118.11 per inspection once 3 or more inspections are needed for the same correction |
| Permit extension / revision | $154.05 (one extension allowed); $821.60 to modify an issued permit |
| Work without a permit | Double the permit fee |
The bands do not chain (the $25,000.01 band restarts at $495, not at the $560.50 the band below reaches, and the bands above $100,000 also restart), so price each project inside its own band. Worked example. Take a $60,000 addition: Mukilteo charges $866.25 for the first $50,000 and $10.50 for each of the next ten thousands, so the permit fee is $971.25. With 75% plan review ($728.44) and the $6.50 single-family state fee the bill is $1,706.19, plus the 3% technology fee and any plumbing, mechanical or L&I electrical permit.
New homes also pay impact fees at issuance in 2026: a park fee of $3,572 and a traffic fee of $7,711.07 per single-family, duplex or townhome unit ($1,770.50 and $3,855.54 for an ADU). The Mukilteo School District’s fee is $0 for single-family homes and $1,148 or $2,985 per apartment, plus a $150 City administrative charge.
Rather not deal with the building department?
Get a free quote →Trade permits and who may pull them
Mukilteo’s fee schedule says it in one line: electrical permits are issued by L&I, and the city is not on L&I’s list of local electrical programs. Wiring, panel changes, EV chargers and solar wiring are therefore L&I’s, while the City issues the plumbing, mechanical, gas piping and fire system permits for the same job. Solar panels also need a City fire permit ($256.75), and battery systems one priced by size ($236.21 plus $61.62 to $256.75).
Who issues what
- Building, plumbing, mechanical, fire and engineering: City of Mukilteo, in SmartGov
- Electrical, including the owner’s own wiring permit: L&I
- Water and sewer connections: the Mukilteo or Alderwood water and wastewater district serving the lot
- Gas service: Puget Sound Energy; electric service: Snohomish County PUD
Owners doing their own work
- A property owner who acts as the contractor signs the City’s Property Owner Acting as Contractor Waiver, found in the portal’s document library
- The same library holds the gas piping test affidavit used when new gas lines are pressure tested
- If you hire instead, our Washington licensing section covers registration and trade certificates
How to apply for a Mukilteo building permit
Use the portal’s parcel search and the City’s GIS maps to check the zone, critical areas, shoreline jurisdiction and flood zone; ask Planning by email or book a free pre-application meeting for anything unclear.
File any shoreline exemption, floodplain, tree or fence modification permit the lot needs, and get the water availability letter from the water district for a new house or detached ADU.
Work through the residential or commercial checklist, the 2021 energy worksheet and the building height worksheet; new houses need their engineering permit package as well.
Register on the online permit center, start the application and upload every document at once. The application counts as complete only when the review fees are paid.
Reviewers post comments in the portal; send revised sheets there as a resubmittal.
Pay the permit fee, impact fees and state fee in the portal or at City Hall, print the issued permit and approved plans, and buy the L&I electrical permit.
Want this handled start to finish?
Get a free quote →Review, corrections and what causes delay
An application is not complete until its review fees are paid, and the City may hold a permit until every fee is settled. Plan additions are billed by the hour with a 1-hour minimum. The City may hire a consultant for specialist, short-staffed or expedited reviews, billed to the applicant plus a 15% administrative fee. A new house filed without its engineering permit, or without the water availability letter, is incomplete under the checklist.
Inspections in Mukilteo
City inspectors work Monday to Thursday. Building, fire and planning inspections must be requested by 3 p.m. the day before, through the portal or by email to the Building Department; engineering inspections for clearing, grading, right-of-way and stormwater need 72 hours’ notice and can also be booked on extension 7. A morning or afternoon slot can be asked for but is not guaranteed.
A permit may be extended once for $154.05; a completion permit costs half the original permit fee. Repeated failed inspections on the same item cost $118.11 each from the third visit, and a stand-alone certificate of occupancy is $118.11.
Mukilteo permit search and official resources
Anyone can search permit status, inspection results and issued documents in the SmartGov portal, by permit number or through the parcel search; older files are requested through the City’s public records request page. Mukilteo is a participating community in the National Flood Insurance Program, with a current effective FEMA map dated June 19, 2020.
- Mukilteo Building & Permits: hours, inspections, regulations
- Do You Need a Permit for That? (homeowner projects)
- Mukilteo SmartGov online permit center
- Portal document library: checklists, worksheets, owner waiver
- Residential building permit checklist (PDF)
- 2026 Master Fee Schedule, Resolution 2026-03 (PDF)
- MMC Title 15: building and construction
- Planning and Community Development Department
- Public records request
- Snohomish Health District permits (septic and wells)
- L&I list of cities with their own electrical permits
Inspections are where schedules slip.
Get a free quote →Mukilteo building permit FAQ
Who issues building permits in Mukilteo?
The City’s Permit Center, part of Planning and Community Development, at City Hall, 11930 Cyrus Way (425-263-8000). Wiring goes to L&I.
Is the Mukilteo permit counter open on Fridays?
No. City Hall is closed on Fridays; the counter is open Monday to Thursday, 8 a.m. to noon and 1 to 5 p.m., and inspections also run Monday to Thursday.
How much is a building permit in Mukilteo?
For a $60,000 addition in 2026 the permit fee is $971.25 and plan review $728.44, plus the $6.50 state fee and a 3% technology fee. The smallest valuation permit is $135.
Do I need a permit to replace my roof?
Yes. The City requires a permit for every re-roof, overlays included; a single-family re-roof is $159.19 plus the state fee in 2026.
Do I need a permit for a shed or deck?
Not for an unheated one-story shed of 200 sq ft or less with walls no taller than 8 feet, or a deck of 200 sq ft or less that stays within 30 inches of grade.
How tall can a fence be without a permit?
Zoning allows 6 feet (4 feet in the front setback) without a fence modification; a modification allows up to 8 feet, and a fence over 7 feet also needs a building permit.
How do I schedule an inspection?
Request building and fire inspections in the portal by 3 p.m. the day before; engineering inspections need 72 hours’ notice.
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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.
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More Washington permitting guides
Snohomish County
Read guide →Arlington
Read guide →Edmonds
Read guide →Newcastle Building Permit Guide
Read guide →Oak Harbor Building Permit Guide
Read guide →Okanogan County Building Permit Guide
Read guide →This guide is provided by Alliance Permitting for general information about Mukilteo permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.