Zoning, building permits and septic rules in the Town of Colma, California

At a glance

Zoning

Colma adopts and administers its own zoning ordinance¹

Building permits

Issued by the Town of Colma Building Division, with inspections²

Septic

Not confirmed inside town limits; ask San Mateo County Environmental Health Services³

Manufactured homes

Permitted in the R and R-S residential zones⁴⁵

Residential height limit

36 feet in R, 27 feet in R-S⁶⁷

RV and tiny-home living

Not confirmed; ask the Planning Department⁸

Who to call

Contact details are copied from each office’s official page and were checked against it on October 16, 2026.

Does Colma have zoning, and what does it mean for homes, lot size and setbacks?

Yes. The Town of Colma adopts and administers its own zoning ordinance, and no building or land inside the town may be used except as the zoning code allows¹. The Planning Department maintains and administers the Colma Zoning Code⁸.

Two residential zones matter most for a home. In the R Residential Zone, a single-family dwelling or a manufactured home is a permitted use⁴. The same two uses are permitted in the R-S Sterling Park Neighborhood Residential Zone⁵.

In the R zone, lots need a minimum average width of 33.33 feet and a minimum depth of 100 feet⁹. The R-S zone uses the same two figures¹⁰. Structures in R are capped at 36 feet⁶; in R-S the cap is 27 feet⁷.

What are the setback rules in Colma's residential zones?

In the R zone, the front setback is 15 feet and the side setback is 10% of lot width or 10 feet, whichever is less¹¹. The rear setback in R is 25% of total lot area, not to exceed 25 feet or 15 feet, with Section 5.03.082(3) adding an exception¹¹.

In the R-S zone, the dwelling sits 15 feet from the front property line and the garage 19 feet, and at least 60% of the front setback area must be landscaped¹². Rear setbacks in R-S are 25 feet for a two-story house and 15 feet for a one-story house, and the side setback is 10% of lot width or 10 feet, whichever is less¹².

We could not confirm a residential lot-coverage percentage or a minimum dwelling size in these zones, so ask the Planning Department before you design⁸.

Do you need a building permit in Colma, and who issues it?

Building permits inside the Town of Colma come from the Town's own Building Division, which also conducts building inspections². The Division says it guides applicants through plan review and permit requirements².

We could not confirm the full list of work that needs a Colma building permit, or any owner-builder exemption inside town limits. Call the Building Division at (650) 757-8888 before you assume any project is exempt². California's owner-builder licensing exemption exists statewide, but it is a licensure rule and does not itself remove a permit requirement¹³.

San Mateo County's Planning and Building Department handles building permits only for unincorporated land¹⁴. A Colma address belongs at the Town counter, not the county's.

How do septic permits work inside Colma?

We could not confirm who permits septic systems or wells on parcels inside Colma. County sources do not state whether San Mateo County Environmental Health's service area includes incorporated Colma, and no Colma rule on septic was located.

For context, San Mateo County requires a permit from Environmental Health to install an individual sewage disposal system elsewhere in the county¹⁵. Environmental Health administers local septic oversight under a state-approved program¹⁶. Ask Environmental Health Services at (650) 372-6200 whether a septic or well permit applies to your Colma address³.

We also could not confirm whether a new Colma home must connect to public sewer and water. Ask the Building Division when you apply².

Can you live in an RV or tiny home on your land in Colma?

We could not confirm any Colma rule on living in an RV, temporary camping, or tiny homes on private land. Ask the Planning Department at (650) 757-8888 before you move one onto a lot⁸.

Do not use San Mateo County's RV rules as a stand-in. Those apply to unincorporated land, and the county's temporary-living provision is tied to its own zoning chapter, not to incorporated towns¹⁷. Manufactured homes are the one factory-built option the Colma zoning code confirms, in the R and R-S zones⁴.

Building a home in Colma: the steps, in order

1. Confirm the parcel is inside Colma and not unincorporated county land; the Building Division points unincorporated or Broadmoor addresses to the county².
2. Check the parcel's zoning district with the Planning Department, since lot size, height and setbacks differ between R and R-S¹.
3. Ask the Planning Department which planning approvals your project needs⁸.
4. Apply to the Building Division for a building permit and plan review².
5. Ask San Mateo County Environmental Health Services whether any septic or well permit applies to the address³.
6. Schedule building inspections with the Building Division as work proceeds².

What stays with San Mateo County, and what to check before you buy in Colma?

Land outside Colma's limits follows San Mateo County's rules instead; see the San Mateo County page for unincorporated land. The county's zoning information does not cover properties within city limits, so a Colma parcel's zoning comes from the Town¹⁸.

County-level figures give context only. San Mateo County's typical home value is about $1,595,764¹⁹ and its effective property tax rate is about 0.6%²⁰. Confirm flood, driveway and fee details with the Town: we could not confirm a Colma fee schedule, driveway rules or floodplain standards beyond a flood hazard zone in the zoning code².

Watch-outs

• Some addresses with a Colma mailing address are actually unincorporated or in Broadmoor, where San Mateo County, not the Town, handles building permits².
• We could not confirm Colma's permit exemptions, owner-builder rules, fee schedule or septic authority; call the Building Division before you spend money on plans².
• Residential zoning limits differ between the R and R-S zones, so confirm your parcel's district before using any height or setback figure¹.

Sources

1. Colma Municipal Code Chapter 5.03 Zoning (Town of Colma), quoted and re-checked
2. Town of Colma Building Division (colma.ca.gov)
3. San Mateo County Environmental Health Services (smcgov.org)
4. Colma Municipal Code Chapter 5.03 Zoning (Town of Colma), quoted and re-checked
5. Colma Municipal Code Chapter 5.03 Zoning (Town of Colma), quoted and re-checked
6. Colma Municipal Code Chapter 5.03 Zoning (Town of Colma), quoted and re-checked
7. Colma Municipal Code Chapter 5.03 Zoning (Town of Colma), quoted and re-checked
8. Town of Colma Planning Department (colma.ca.gov)
9. Colma Municipal Code Chapter 5.03 Zoning (Town of Colma), quoted and re-checked
10. Colma Municipal Code Chapter 5.03 Zoning (Town of Colma), quoted and re-checked
11. Colma Municipal Code Chapter 5.03 Zoning (Town of Colma), quoted and re-checked
12. Colma Municipal Code Chapter 5.03 Zoning (Town of Colma), quoted and re-checked
13. Owner-Builder Overview, quoted and re-checked
14. Apply for a Permit, quoted and re-checked
15. Land Use, Septic & Wells, quoted and re-checked
16. Land Use, Septic & Wells, quoted and re-checked
17. San Mateo County Zoning Regulations, quoted and re-checked
18. Get Zoning Information, quoted and re-checked
19. Typical home value (Zillow): Bolthole Index county data
20. Effective property tax rate: Bolthole Index county data

Written October 16, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.