Mill Creek, Washington Building Permit Guide

The City of Mill Creek’s Building Division reviews plans, issues building, mechanical and plumbing permits and inspects the work, and all of those applications are made on the City’s OpenGov portal. Wiring permits are bought from the state Department of Labor and Industries (L&I), whose south Everett office at 729 100th Street SE (425-290-1300) is closed on Wednesdays. Under the 2026 Master Fee Schedule, plan review adds 70% to the valuation-based permit fee, and even a fence, replacement included, needs an $88 permit.

The Permit Counter is at City Hall North, 15720 Main Street, Suite 110A. Walk-in help runs Monday to Thursday from 9 a.m. to noon, and the afternoons from 1 to 5 p.m. are kept for booked appointments, which can be reserved online. The counter’s line is 425-551-7254. Mill Creek’s 2025 Census estimate was 20,902 people.

Mill Creek permits apply inside the city limits. The surrounding unincorporated land, including the Municipal Urban Growth Area the City may annex, is permitted by Snohomish County.

What requires a building permit in Mill Creek?

Mill Creek wrote its own list of house projects that need no building permit: section 15.04.055 of the Mill Creek Municipal Code (MCMC) replaces the residential code’s exemption list, and section 15.04.015 adds temporary job shacks to the commercial list. The City’s homeowner flyer (updated August 2025) puts the general rule plainly: no building, mechanical or plumbing system may be built, altered, replaced, moved or demolished without a permit unless an exemption applies.

Two points are easy to miss. Fences are not on Mill Creek’s exemption list at all, which is why the flyer lists every new or replacement fence as permitted work. And a deck stays exempt only while it is freestanding: the flyer mentions just the 30-inch height, but the adopted code also excludes decks attached to the house.

What the city decides and what the state holds

Chapter 15.04 MCMC (last updated by Ordinance 2024-914) adopts the 2021 International Building, Residential, Mechanical, Fuel Gas, Fire and Existing Building codes, the Uniform Plumbing Code and the Washington State Energy Code with the state’s amendments; Mill Creek’s design values are a 25 psf ground snow load, seismic category D1, 110 mph wind and a 12-inch frost depth. The City chooses its exemption list, its fees (set by Council resolution under chapter 3.42 MCMC), its tree, grading and critical areas rules, and sends building code appeals to its hearing examiner.

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

Mill Creek building department: who handles permitting

The Building Division, within Community Development and Planning, issues building, mechanical and plumbing permits for new and existing construction and does the plan review and field inspections. The Permit Counter staff also help with land disturbing activity, land use, right-of-way and tree removal permits. Fire permits are filed in the same OpenGov portal, with fees set under an interlocal agreement with South County Fire, which provides the city’s fire service.

Permit types

Residential permits

House projects fall into a few OpenGov record types: a building permit for new homes, additions, ADUs, decks and remodels, priced by valuation; flat-fee permits for fences ($88), re-roofs under the residential code ($175) and residential demolitions ($350); and separate mechanical and plumbing permits. A simple job such as a water heater or furnace swap can use the express mechanical or plumbing permit, which costs $175 for up to four fixtures and $18 for each extra one.

Valuation, under MCMC 15.04.030, is the full value of the work, labor and materials, including the contractor’s overhead and profit; the applicant gives an estimate and the Building Official sets the figure, using the current ICC building valuation data for new floor area.

Building or remodeling a home here? Alliance handles residential permit applications, so the crew isn't waiting on the counter.

Commercial permits

Commercial buildings, tenant improvements and signs are priced on the same valuation table, with 70% plan review, the $25 commercial state fee and separate mechanical and plumbing permits; a commercial re-roof is also priced by valuation and a commercial demolition is $700. Fire alarm and sprinkler permits run $300 for up to 5 devices (plan review included), $500 for 6 to 15 and $1,000 for 16 to 25, plus $10 per added device; fire pumps and standpipes are $600 each. Commercial projects and those with 11 or more homes go before the Design Review Board, a Process II land use review with a $4,375 minimum deposit.

For tenant improvements and new commercial builds, Alliance handles commercial building permits through issuance. More on this: commercial building permits explained.

What comes before the building permit

Removing any tree 6 inches or more in diameter at 4.5 feet above ground, or any tree in a critical area, roadway or property buffer, needs a tree permit (free for a standard tree, $175 for a critical area tree); many subdivisions also carry tree preservation plans. A land disturbing activity permit, the former clearing and grading permit, covers clearing, fill, excavation and retaining walls that a building permit does not, and includes the stormwater site plan under the 2019 Ecology manual; it is priced at 1.5% of the engineer’s estimate for review and 3% for inspection. Work in a street needs a right-of-way permit with a site plan and traffic control plan (Type I $350).

The City has been updating its critical areas rules in chapters 17.32 and 18.06 MCMC (the SEPA determination of non-significance for the update was issued in December 2025), and flood hazard areas are regulated under chapter 15.20. The City runs no water, sewer, gas or electric utility: water and sewer come from the Alderwood Water and Wastewater District or the Silver Lake Water and Sewer District, and any septic system is a Snohomish Health District matter.

Mill Creek permit costs and fees

Fees come from the 2026 Master Fee Schedule, adopted by Resolution No. 2025-810 and in force since January 1, 2026. Mill Creek prices permits as a percentage of value, and the bands join up: each one starts where the one below ends. Plan review fees are paid up front, because an application is not complete until they are.

Worked example. Mill Creek works in percentages, so a $60,000 addition costs $1,010 plus 1% of the $10,000 over $50,000: $1,110. Add 70% plan review ($777), the 3% technology fee on both ($56.61) and the $6.50 residential state fee, and the City collects $1,950.11; plumbing, mechanical and L&I electrical permits are extra.

New homes also pay impact fees. Park fees under Resolution 2013-503 are set per unit by park type (up to $3,308.45 for a single-family home for neighborhood park land and development), the City’s transportation fee is $3,900 per PM peak-hour vehicle trip under Ordinance 2018-838, and the Everett School District fee is $9,118 for a single-family house. If no work has been done, up to 80% of permit fees can be refunded, but never plan review.

Trade permits and who may pull them

The fee schedule and the codes page both send electrical work to L&I: Mill Creek does not appear on L&I’s list of cities with their own electrical inspection, so service changes, circuits, EV chargers and solar wiring are permitted and inspected by the state. The City issues the mechanical, gas piping and plumbing permits, and South County Fire’s fees apply to fire alarm, sprinkler and solar panel permits ($600 for a solar permit, with plan review and one inspection).

How to apply for a Mill Creek building permit

Review, corrections and what causes delay

Appeals of a Building Official’s decision go to the City’s hearing examiner rather than a board of appeals. A tree removal or grading permit lasts six months, with one extension of up to six more, so time the site work to the building schedule. Extending a building application or permit costs $350 or half the permit fees, whichever is less.

Inspections in Mill Creek

Inspections are requested in OpenGov or by calling 425-338-1133. A request made before 3:30 p.m. gets an inspection on the next business day; one made later is scheduled for the business day after that. A re-inspection is billed at one and a half times the hourly rate with a 1-hour minimum, and an evening, weekend, holiday or expired-permit inspection at double the rate with a 2-hour minimum. A certificate of occupancy issued outside a building permit costs $175.

Mill Creek permit search and official resources

The OpenGov portal’s public search shows the status of building permits by address or record number. Older permit files and plans are requested as public records through the City’s GovQA request center. On flood insurance, Mill Creek is a participating community in the National Flood Insurance Program; FEMA’s status book lists June 19, 2020 as its current effective map.

• Mill Creek Permits and Licensing: counter hours and contacts
• Building permits: apply and schedule inspections
• Building codes and design criteria
• Do I Need a Permit? flyer, August 2025 (PDF)
• 2026 Master Fee Schedule, Resolution 2025-810 (PDF)
• Mill Creek Municipal Code (Title 15, buildings)
• Tree removal permits
• Land disturbing activity permits
• OpenGov permit status search
• Public records requests (GovQA)
• October 2026 annexation decision
• L&I list of cities with their own electrical permits

Mill Creek building permit FAQ

Who issues building permits in Mill Creek?

The City’s Building Division, through the Permit Counter at City Hall North, 15720 Main Street, Suite 110A (425-551-7254). L&I issues electrical permits.

Do I need a permit to replace my fence in Mill Creek?

Yes. Fences are not exempt in Mill Creek, and the City lists replacement fences as permitted work. The fence permit is $88 in 2026.

How much is a building permit in Mill Creek?

A $60,000 project pays a $1,110 permit fee, $777 plan review, a $56.61 technology fee and the $6.50 state fee: $1,950.11 in 2026.

Do I need a permit for a deck?

Yes if it is attached to the house, serves the exit door or stands more than 30 inches above grade at any point. A low freestanding deck is exempt.

Do I need a permit for a new roof?

Only if the sheathing is removed or replaced; in-kind re-roofing over the existing sheathing is exempt. A residential re-roof permit is $175.

When will my inspection happen?

The next business day if you request it before 3:30 p.m., online or at 425-338-1133.

Can I cut down a tree on my lot?

Not without a permit if it is 6 inches or more in diameter at chest height, or in any buffer. Standard tree permits are free.

Simplify Mill Creek permitting with Alliance Permitting

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 Mill Creek permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.