GetYourPermit

ADU permit guide for Belmont, California

San Mateo County, California

Building Division / Permit Center reviews local ADU permits through the City Online Portal System. Use this page to plan the local process and the fee questions to verify before you submit.

Prepared by GetYourPermit editorial teamReport an error

Permit fee planning by size

GetYourPermit research · 1 published reference line

ADU sizeResearched range
600 sq ft$4,300 – $10,550
800 sq ftimpact-fee band$9,150 – $21,150
1,000 sq ft$10,950 – $24,850
1,200 sq ft$12,650 – $28,750
Build a Belmont permit reportDetailed fee breakdown

Getting the permit

Department
Building Division / Permit Center
Where to apply
City Online Portal System
View the full 6-step permit process

Reference pages to verify