GetYourPermit

ADU permit guide for Cupertino, California

Santa Clara County, CaliforniaReviewed August 28, 2026

Building Division 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 · 5 published reference lines

ADU sizeResearched range
600 sq ft$11,568 – $16,068
800 sq ftimpact-fee band$15,068 – $23,068
1,000 sq ft$18,600 – $29,100
1,200 sq ft$21,000 – $33,150
Build a Cupertino permit reportDetailed fee breakdown

Getting the permit

Department
Building Division
Where to apply
City Online Portal System
View the full 5-step permit process

Reference pages to verify