Hillsborough plan check and resubmittal guide
What we could verify about the Town of Hillsborough’s permit office from government and permit portal pages, what California law says about plan check there, and how to answer a correction letter. Each fact links to its source.
The Town of Hillsborough permit office
- Building Division: (650) 375-7411 (hillsborough.net, checked October 31, 2026)
- Address: 1600 Floribunda Ave., Hillsborough, CA 94010 (hillsborough.net, checked October 31, 2026)
- Resubmittal instructions
- eTRAKiT
- Building department page
Links and facts checked on October 28, 2026.
What to include
- Attach all resubmittal materials
- Only complete plan sets
From Hillsborough’s own page, read October 30, 2026: hillsborough.net
Codes its letters cite
Building code named on the city’s pages: 2025 California Code of Regulations Title 24.
Local amendments to the building code
Filed local amendments with the California Building Standards Commission (ordinance 799).
Sections the Town of Hillsborough changes from the state code (summaries in our words; read the ordinance for the exact text):
- Municipal code 15.10.050: Adds Energy Reach Code for new low-rise residential construction to Chapter 15.
The amendments: hillsborough.net
Hillsborough and San Mateo County
Hillsborough is in San Mateo County. See the San Mateo County guide.
California rules every plan check here follows
These come from California law and state agencies, so they apply in Hillsborough as well. Each links to its source.
Building code in force
The 2025 edition of Title 24, the California Building Standards Code, has been in effect since January 1, 2026.
Source: California Building Standards Commission, checked October 31, 2026
Energy code
If your permit application was filed on or after January 1, 2026, the project has to meet the 2025 Energy Code.
Source: California Energy Commission, checked October 31, 2026
Energy forms with the application
A building permit application covered by the energy code (Part 6) must include at least one copy of the required energy compliance documents.
Source: California Energy Commission, 2025 Building Energy Efficiency Standards, checked October 31, 2026
Green building code (CALGreen)
The 2025 edition of CALGreen, the state green building code (Part 11), took effect on January 1, 2026.
Source: California Building Standards Commission, checked October 31, 2026
ADU decision deadline
If the city or county has not approved or denied a complete application for an ADU or junior ADU within 60 days, the application is treated as approved (Gov. Code § 66317).
Source: California Department of Housing and Community Development, ADU Handbook, checked October 31, 2026
ADU denials must explain the fix
When a city or county denies an ADU or junior ADU application, it must send written comments within 60 days that list each problem and explain how you can correct it.
Source: California Department of Housing and Community Development, ADU Handbook, checked October 31, 2026
Building permits for approved housing projects
For housing projects that already have planning approval, the city or county has 15 business days to say whether a building permit application is complete, then 30 or 60 days, depending on how many units are proposed, to decide whether it meets the standards.
Source: California Department of Housing and Community Development, Housing Law Fact Sheets, checked October 31, 2026
What a good response to plan check corrections has
General guidance, not the Town of Hillsborough’s own rules. Check its page before you resubmit.
- Answer every comment, in the reviewer’s order and numbering, so nothing is missed.
- Say plainly what you changed for each comment, or why no change is needed.
- Name the sheet and detail where each change is, so the reviewer can find it fast.
- Mark changes on the drawings (clouds or deltas are common) and keep sheet numbers the same.
- Send the response letter, the revised drawings and any new calculations together.
Other California city guides
How we help
Send us the whole correction letter. We draft a response to every comment and list the drawing changes sheet by sheet. Your first letter is free. You review each response, then you sign and submit to the Town of Hillsborough yourself.
Cleared to Build is an independent service. We are not the Town of Hillsborough and are not affiliated with it.
Upload your correction letterOnly one comment to answer? Try the free one-comment tool.
Questions
How long does Hillsborough take to review a resubmittal?
For housing projects that already have planning approval, the city or county has 15 business days to say whether a building permit application is complete, then 30 or 60 days, depending on how many units are proposed, to decide whether it meets the standards. Ask the Town of Hillsborough for its current review times.
Does Hillsborough charge for another plan review?
This guide doesn’t list fees. Ask Building Division at (650) 375-7411 before you resubmit.
How many rounds of corrections can Hillsborough send?
This guide doesn’t list a limit. Answering every comment fully the first time is the surest way to fewer rounds; ask Building Division at (650) 375-7411 if unsure.
Is Cleared to Build part of the Town of Hillsborough?
No. Cleared to Build is an independent service, not affiliated with the Town of Hillsborough or any permitting agency. You submit to the city yourself.