📋 Official Permit Guide · WA

Seattle Commercial Addition/Alteration Permit Guide

Cut through the red tape. Everything you need to know about getting a building permit in Seattle — fees, timelines, required documents, and how to avoid the most common rejections.

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🗓 Data verified: March 2026 Platform: generic

Permit Types in Seattle

Not every project requires a permit. Here's what you need to know for common project types.

Commercial Addition/Alteration ✓ Permit Required

Expanding or renovating existing commercial space beyond what a subject-to-field-inspection permit covers.

⏱ Avg approval: 58 days
Auto-fill your commercial addition/alteration permit →

Permit Fee Schedule

Fees in Seattle are based on project valuation, type, and square footage. These are the current standard fees.

Category Fee Type Amount Unit Notes
Fee schedule data coming soon.
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Permit Process Timeline

From application to final inspection — here's what to expect at each stage in Seattle.

1
Intake

The City formally accepts the permit application.

💡 Ensure application materials are complete to avoid delays.
2
Initial Plan Review

The City conducts the first review of the application.

💡 This is typically the largest phase in the construction permit process.
3
Correction Notice

The City reviews the application and issues a notice of required updates or corrections.

4
Applicant Update and Resubmission

The applicant updates their plans and resubmits the application to the City.

💡 Total calendar days to obtain a permit is roughly twice the calendar days in City control due to applicant response time.
5
Issuance

The City issues the permit once all issues are resolved.

Required Documents Checklist

Gather these documents before applying to avoid delays. Required items are marked with ✓.

Site Plan Guidelines and requirements are found in Tip 103.
Plans and Drawings General standards for plans and drawings are found in Tip 106.
City of Seattle Business License Required for small business permit facilitation eligibility.
Don't want to gather all this yourself? Use our free permit wizard — we'll organize everything →

Top Reasons Permits Get Rejected in Seattle

Learn from the most common mistakes that cause delays and rejections — so yours doesn't end up on this list.

Common mistakes data coming soon.

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Licensing & Insurance Requirements

What credentials must your contractor have in Seattle?

Contractor License ✓ Required
Bond Required ✗ Not Required
Liability Insurance ✗ Not Required

Small businesses must have a current City of Seattle business license to be eligible for permit facilitation services.

Building Permit FAQ — Seattle

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⚠ Disclaimer: This information is provided for general reference only. Always verify requirements directly with your local building department before beginning any project. Permit requirements, fees, and timelines are subject to change.