Planning & Building
San Mateo County building permit services. Confirm which county or city agency handles your property before applying.
Planning and Building gives nine-digit APN search instructions and the LAND USE → Unincorporated SMC Zoning layer. Multiple zoning overlays may apply; a map result must be read with each relevant ordinance section.
- Availability · Planning GIS lookup input requirement
- You will need the 9-digit APN (0XX-XXX-XX0) for the property. The GIS Database may not be able to find property-specific information by address.
Source & saved evidence
Official county map/provider evidence: exact named map, actual layer list, access instructions or limitation
You will need the 9-digit APN (0XX-XXX-XX0) for the property. The GIS Database may not be able to find property-specific information by address.
Agent source review: October 26, 2026 · Snapshot
20adb568ee653c8c - Availability · Multiple zoning overlays require the applicable ordinance sections
- Each “layer” represents a distinct chapter or section in the County’s Zoning Regulations.
Source & saved evidence
Official county map/provider evidence: exact named map, actual layer list, access instructions or limitation
Each “layer” represents a distinct chapter or section in the County’s Zoning Regulations.
Agent source review: October 26, 2026 · Snapshot
20adb568ee653c8c
Source & saved evidence
Official county map/provider evidence: exact named map, actual layer list, access instructions or limitation
Click the “Unincorporated SMC Zoning" layer” check box to display Zoning Districts.
Agent source review: October 26, 2026 · Snapshot 20adb568ee653c8c