Planning to build a new home, add an ADU, finish a basement, install a pool, replace a roof, or do any other construction or renovation project in unincorporated San Mateo County, California? You will need a building permit from the San Mateo County Building Division (part of the Planning and Building Department).
Most people get stuck on the same questions: “How do I actually apply?”, “What will it cost in 2026?”, “How long does approval really take?”, “What documents do they want?”, and “What are the hidden tricks that make this process go faster?” This long, practical guide answers all of those questions with real-world steps, insider tips, and the exact workflow that experienced contractors and smart homeowners use every day in San Mateo County.
San Mateo County Building Department Contact Details 2026
Service | Details |
|---|---|
Building Division Address | 455 County Center, 4th Floor, Redwood City, CA 94063 |
Main Phone | (650) 363-4220 |
Building Permits | (650) 363-4220 |
Inspections | (650) 363-4220 |
Email | building@smcgov.org |
Hours | Monday–Friday, 8:00 AM – 5:00 PM |
How to Apply for a Building Permit in San Mateo County, California – Complete Micro Step-by-Step Guide (2026)
- Confirm your project is in unincorporated San Mateo County (not inside a city).
- Register or log into the Accela Citizen Access portal.
- Prepare detailed construction drawings, site plans, specifications, CalGreen checklist, and supporting documents.
- Determine if your project qualifies for Express or Over-the-Counter processing (many roofing, windows, solar, HVAC, and water heater replacements do).
- Submit the complete application online through the Accela portal with all attachments.
- Pay the required application and plan review fees online (credit card service fees apply).
- Monitor your application status in the portal and respond quickly to any review comments.
- Once approved, pay the remaining permit fees and print/post the permit visibly at the job site before starting work.
- Schedule inspections through the Accela portal or by calling the Building Division.
San Mateo County Building Permit Fees 2026 – What You’ll Actually Pay
Fees are valuation-based with plan review fees typically 65%–100% of the permit fee. Additional charges include technology surcharges, re-inspection fees, and impact fees. Always use the online fee calculator or download the latest fee schedule before submitting to budget accurately.
Insider Tips & Tricks That Save Time and Money in San Mateo County
- Use the Accela portal for everything possible — it reduces counter visits and speeds up tracking.
- Submit complete and clearly labeled drawings the first time — incomplete submissions are the #1 reason for delays.
- Call (650) 363-4220 early in the morning for questions — staff is most responsive then.
- For smaller projects (roofing, windows, solar, HVAC, water heater), confirm Express or Over-the-Counter eligibility first.
- Pay with cash or check in person if possible to avoid credit card service fees.
- Schedule inspections well in advance through the portal.
- Coordinate with Planning, Fire, or other departments early if your project involves multiple approvals.
Frequently Asked Questions
How do I search for existing building permits in San Mateo County?
Use the Accela portal to search by property address or permit number.
How long does it take to get a building permit in San Mateo County?
Express or Over-the-Counter permits can be issued quickly. Standard projects with full plan review typically take 7–20 business days if submitted completely.
Can I pull my own permit as an owner-builder in San Mateo County?
Yes. Owner-builders can apply but must take full responsibility for code compliance and job safety.
What are the re-inspection fees in San Mateo County?
Re-inspection fees apply for failed or missed inspections. Exact amounts are in the current fee schedule.
Do I need approvals from other departments?
Yes. Many projects require review from Planning, Fire, or other divisions. Coordinate early to avoid delays.
Last reviewed: April 15, 2026
Khushboo Bobade is a public records researcher and editorial writer specializing in government service documentation and construction permit systems.
Her research focuses on explaining building permits, inspection procedures, zoning regulations, and public permit records maintained by local government building departments across the United States.
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