Sign Regulations in San Mateo County, CA (2026)

1 county-level rule, plus city-specific rules for 2 cities in San Mateo County, California.

Verified from official government sources

Note: These county rules apply to unincorporated areas of San Mateo County. If you live within an incorporated city, that city's own rules apply: see the city list below.

Window Signs

In the NMU-ECR District along El Camino Real in unincorporated North Fair Oaks, San Mateo County caps window signs at 25 percent of the window's glass area under Zoning Regulations Sec. 8.132.050(6)(e). Window signage is exempt from the parcel's overall sign display cap, but the same subsection bans billboards, off-premises signs, and any flashing, animated or beacon-style sign in this corridor.

San Mateo County NMU-ECR Window Sign Area Cap

Some Restrictions

San Mateo County Zoning Regulations § 8.132.050(6)(e)

c. Maximum Number of Signs. The maximum number of signs allowed on a parcel is one sign per parcel, or one sign per each 200 feet of parcel street frontage, or one sign per use, whichever is greatest. d. Maximum Total Sign Display Area. The maximum total display area for all signs on a parcel is three-quarters square foot per foot of parcel street frontage. e. Maximum Window Sign Area. Signs lo...

Full ordinance details →Official source ↗

Sign Regulations by City in San Mateo County

2 cities in San Mateo County have their own sign regulations rules. Each link goes to that city's dedicated page with code citations.

San MateoPop. 105,661

1 verified rule • Political Signs

Redwood CityPop. 84,518

3 verified rules • Garage Sale Signs, Political Signs

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