Sign Regulations in Sonoma County, CA (2026)

2 county-level rules, plus city-specific rules for 2 cities in Sonoma County, California.

Verified from official government sources

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

Political Signs

Sonoma County requires a zoning permit for every campaign or political sign under Zoning Code § 26-84-030(f). In R1 districts a parcel holds two single-faced signs of 16 square feet or one double-faced sign of 16 square feet per face; every other district allows 32 square feet per face. Signs go up no earlier than 90 days before the election and come down within 20 days of the close of the campaign.

Sonoma County Campaign and Political Sign Rules

Significant Restrictions

Sonoma County Code § 26-84-030(f)

(f) Campaign and Political Signs. Campaign and political signs may be permitted in any zoning district upon being issued a zoning permit and are subject to the following criteria: (1) No more than two (2) sixteen square foot (16 ft 2 ) single-faced, nor more than one (1) double faced or wing type, maximum sixteen (16) square feet on each face, political or campaign sign is permitted, per parcel...

Full ordinance details →Official source ↗

Freeway-Facing Signs

Billboards and other outdoor advertising structures facing Highway 101 or any other freeway in unincorporated Sonoma County need a use permit and must sit at least 1,000 feet from the next outdoor advertising sign, measured along the highway's centerline.

Sonoma County Freeway-Facing Sign Rules

Some Restrictions

Sonoma County Code § 26-84-030(g)(3)(i)

(3)Outdoor advertising structures and signs located along roadways which are not designated as scenic corridors shall meet the following spacing requirements:(i)Outdoor advertising structures and signs along any freeway, expressway or limited access highway: no closer than one thousand feet (1,000′) from any other outdoor advertising structure or sign, with the distance to be measured parallel ...

Full ordinance details →Official source ↗

Sign Regulations by City in Sonoma County

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

Santa RosaPop. 178,127

4 verified rules • Digital Billboards, Freeway-Facing Signs

PetalumaPop. 59,776

3 verified rules • Freeway-Facing Signs, Political Signs

All Sonoma County ordinances

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