How Much Does a Seattle Building Permit Cost? (2026 SDCI Fee Guide)
Seattle building permit fees are calculated by SDCI using a formula based on project valuation — not a flat rate, not your contractor's bid, but SDCI's own estimate of what the work is worth. Most homeowners don't know this going in, which means the permit cost line in their budget is either missing entirely or wildly wrong. This guide breaks down exactly how Seattle permit fees are calculated, what real projects cost in 2026, and the additional fees that often catch homeowners off guard.
How Seattle Calculates Building Permit Fees
SDCI uses a valuation-based fee schedule — the larger and more complex the project, the higher the fee. But valuation is not simply your contractor's bid. SDCI uses its own construction valuation table, updated annually, which estimates the fair market cost of construction work by type.
The formula works in tiers:
Projects valued up to $2,000: Flat fee of $200 $2,001–$25,000: $200 base + $8 per $1,000 of valuation above $2,000 $25,001–$50,000: $384 base + $6.40 per $1,000 above $25,000 $50,001–$100,000: $544 base + $4.80 per $1,000 above $50,000 $100,001–$500,000: $784 base + $3.60 per $1,000 above $100,000
These are the building permit fees only — plumbing, electrical, and mechanical permits are calculated separately.
SDCI's valuation for your project may be higher than your contractor's bid. SDCI uses average market rates, not negotiated contractor pricing. If your contractor bids $60,000 for a bathroom remodel but SDCI values that scope of work at $75,000, the permit fee is based on $75,000.
What Real Seattle Projects Cost in Permit Fees (2026)
Here are permit fee estimates for common residential projects based on SDCI's 2026 fee schedule and typical project valuations:
Cosmetic bathroom refresh (no permit required): $0
Full bathroom remodel, same footprint ($35,000 valuation): Building permit: ~$584 Plumbing permit: ~$280 Electrical permit: ~$200 Total: ~$1,064
Full bathroom remodel with layout changes ($55,000 valuation): Building permit: ~$784 Plumbing permit: ~$320 Electrical permit: ~$240 Total: ~$1,344
Full kitchen remodel, same footprint ($65,000 valuation): Building permit: ~$832 Plumbing permit: ~$300 Electrical permit: ~$380 Total: ~$1,512
Kitchen remodel with wall removal ($90,000 valuation): Building permit: ~$976 Plumbing permit: ~$340 Electrical permit: ~$420 Total: ~$1,736
Deck addition ($40,000 valuation): Building permit: ~$704 Total: ~$704
ADU (garage conversion, $140,000 valuation): Building permit: ~$1,944 Plumbing permit: ~$480 Electrical permit: ~$520 Mechanical permit: ~$280 Total: ~$3,224 (not including King County sewer capacity charge)
These estimates assume STFI (Subject-to-Field-Inspection) permit track. Projects requiring full plan review add a plan review fee — typically 65% of the building permit fee — on top of the base permit cost.
Additional Fees That Catch Homeowners Off Guard
The building, plumbing, and electrical permit fees are the most visible costs — but several additional fees can add significantly to your total.
Plan review fee: Projects requiring plan review (structural changes, wall removals, new additions) pay a plan review fee equal to 65% of the building permit fee at time of application. This is paid upfront before review begins and is non-refundable even if you withdraw the application.
State surcharge: Washington State adds a surcharge of 4.5% of the permit fee on top of SDCI's fee. It's small but real.
Seattle Fire Department review: Projects over certain size thresholds or with fire suppression systems require SFD review — typically $200–$600 additional.
Side sewer permit: Any project that connects to or modifies the side sewer (the line from your house to the city main) requires a separate side sewer permit from Seattle Public Utilities — $400–$800.
King County sewer capacity charge: ADU projects and additions that add a residential unit trigger a King County sewer capacity charge. In 2026 this is approximately $8,200 as a lump sum or $77.99/month for 15 years added to your utility bill. This is the fee most ADU owners are surprised by.
For a full ADU project, factor the sewer capacity charge into your budget from day one. At $8,200 lump sum, it's a significant line item that many homeowners don't discover until they're already committed to the project.
Permit Fees in Bellevue, Redmond, and Kirkland
Each city in the Seattle metro has its own fee schedule — Bellevue, Redmond, and Kirkland do not use SDCI and have their own development services departments with independent fee structures.
In general, Bellevue fees run 10–20% higher than Seattle for equivalent projects, reflecting higher staff costs and more thorough review processes. Redmond and Kirkland fees are broadly comparable to Seattle, sometimes slightly lower.
The more significant difference across cities is plan review timeline — Bellevue's Development Services is well-staffed and typically completes first reviews in 4–6 weeks. Seattle's SDCI can run 6–12 weeks for complex projects. If you're planning a major remodel, the city you're in affects your timeline more than your fee total.
| Project Type | Seattle (SDCI) | Bellevue | Redmond | Kirkland |
|---|---|---|---|---|
| Full Bath Remodel | $1,064–$1,344 | $1,200–$1,600 | $950–$1,300 | $950–$1,300 |
| Full Kitchen Remodel | $1,512–$1,736 | $1,700–$2,100 | $1,400–$1,900 | $1,400–$1,900 |
| Deck Addition | $704–$960 | $800–$1,100 | $650–$900 | $650–$900 |
| ADU (Garage Conversion) | $3,224–$4,500 | $3,800–$5,200 | $2,900–$4,100 | $2,900–$4,100 |
Can You Reduce Your Seattle Permit Fees?
Permit fees are calculated by formula and are not negotiable — SDCI doesn't bargain. But there are legitimate ways to minimize permit costs:
Scope work carefully: If your project can be broken into phases — cosmetic work first (no permit), followed by plumbing changes in a second phase — you may be able to reduce the valuation of any single permit application. However, SDCI can and does roll related work into a single valuation if it's clearly the same project.
Accurate valuation: If your contractor's bid is significantly below SDCI's valuation table, you can request a valuation review with documentation. This requires a detailed cost breakdown and is most worth pursuing on larger projects.
STFI vs. plan review: Designing your project to avoid structural changes keeps you in the STFI track and eliminates the plan review fee (65% of permit fee) and the associated timeline. For many homeowners, redesigning to keep walls in place is worth the trade-off.
The biggest permit cost-saving strategy isn't fee reduction — it's timeline management. Every week your project is delayed by permit issues costs money in contractor scheduling, temporary living arrangements, and lost rental income on investment properties. Getting permits right the first time is worth more than any fee savings.
Chief Architect Home Designer Suite 2025
Seattle permit applications for projects requiring plan review need accurate floor plan drawings. Chief Architect Home Designer Suite is the software residential designers and DIY homeowners use to create permit-ready drawings — floor plans, elevations, and 3D views that show SDCI exactly what you're building. Clean drawings on the first submission dramatically reduce correction cycles and permit delays.
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Free Seattle Permit Fee Estimator
Enter your project type and estimated cost — get an instant estimate of Seattle permit fees, trade permit costs, and additional charges to include in your budget.