City Of San Mateo Building Department | Permits, Inspections & Official Contact

Planning to build a new home, add a garage, finish a basement, install a pool, replace a roof, or do any other construction or renovation project in the City of San Mateo, California? You will need a building permit from the City of San Mateo 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.

City of San Mateo Building Department Contact Details 2026

How to Apply for a Building Permit in San Mateo, California – Complete Micro Step-by-Step Guide (2026)

1. Confirm your project is inside the City of San Mateo limits and check zoning/historic requirements.
2. Visit the Customer Self-Service (CSS) Portal and create or log into your account.
3. Prepare detailed construction drawings, site plans, specifications, CalGreen checklist, and any required supporting documents.
4. Determine if your project qualifies for over-the-counter or virtual plan review (many simple alterations and re-roofs can be fast-tracked).
5. Submit the complete application online through the CSS Portal with all attachments.
6. Pay the required application and plan review fees online (credit/debit card service fees apply; cash/check in person avoids them).
7. Monitor your application status in the portal and respond quickly to any review comments or requests for resubmittals.
8. Once approved, pay the remaining permit fees and print/post the permit visibly at the job site before starting work.
9. Schedule inspections through the CSS Portal (inspector will contact you with a 2-hour window).

City of San Mateo Building Permit Fees 2026 – What You’ll Actually Pay

Building permit fees are primarily based on the valuation of the project. Additional itemized fees apply for plan review, technology, subcontract trades (electrical, plumbing, mechanical), and other services. Re-inspection fees are charged for failed or missed inspections. The City publishes an annual Comprehensive Fee Schedule — always check the latest version before submitting.

Insider Tips & Tricks That Save Time and Money in San Mateo

• Submit through the CSS Portal whenever possible — it is faster, tracks everything in one place, and reduces counter visits.
• Prepare complete plans with CalGreen documentation the first time — incomplete submissions are the #1 cause of delays.
• Call (650) 522-7172 early in the morning for questions — permit technicians are most available then.
• For simple projects (re-roofing, water heaters, electrical upgrades, windows), ask about over-the-counter or fast-track options to skip full plan review.
• Pay with cash or check in person if possible to avoid credit card service fees (typically 2-3%).
• Schedule inspections well in advance through the portal — last-minute or same-day requests are difficult.
• Coordinate with Planning Division early if your project involves zoning changes, tree removal, or historic review.

Frequently Asked Questions

Last reviewed: April 15, 2026