Sign Regulations in Sonoma, CA (2026)
4 verified sign regulations for Sonoma, California, sourced directly from the municipal code and official government pages.
Verified from official government sources
Political Signs
The City of Sonoma lets residents put up political, ideological, or religious signs without a sign permit for the 90 days before a valid election, but each sign is capped at 8 square feet, the parcel total is capped at 32 square feet, and every sign must come down within 10 days after the election.
Political Sign Rules in the City of Sonoma
Some RestrictionsSonoma Municipal Code § 18.12.090(L)
Political signs, ideological, religious, or signs having any other message which are displayed within 90 days prior to a valid election held within the city may be displayed without a permit, subject to the following regulations: 1. Size. Each sign shall not exceed eight square feet in area or a total aggregate sign area of 32 square feet on a single parcel. 2. Time. Each sign shall be removed ...
Holiday Displays
The City of Sonoma's sign code does not single out holiday lights, but it does regulate decorative holiday banners and flags: businesses may fly them for up to 45 total days a year for holidays, or for 15 consecutive days for a grand opening or special event, without advertising copy.
Holiday Banner Display Limits in Sonoma
Some RestrictionsSonoma Municipal Code § 18.20.110
Decorative banners and flags may be used for grand opening or special events for a maximum period of 15 consecutive days, or for holidays for a period of no more than 45 total days per year and may be permanently displayed if first approved by the DRHPC. In no event shall advertising copy be displayed on any banner.
Digital Billboards
The City of Sonoma bans moving, flashing, and light-based sign effects outright: § 18.28.026 prohibits moving sign structures, moving lights, and flashing lights, which reaches digital billboards and electronic changeable-message displays that rely on those effects.
Digital and Flashing Sign Ban in Sonoma
Heavy RestrictionsSonoma Municipal Code § 18.28.026
Moving sign structures, pennants, whirligigs, reflectors, reflective signs, moving lights, flashing lights, feather signs, and visible gaseous discharges are specifically prohibited except as permitted under SMC 18.12.020, Administrative review.
Window Signs
The City of Sonoma caps window signs at 20 percent of each window facing a public right-of-way, requires DRHPC review for permanent window signs, and limits any temporary window display to 90 days per year under Municipal Code § 18.20.200.
Window Sign Coverage Limits in Sonoma
Some RestrictionsSonoma Municipal Code § 18.20.200
Permanent or temporary window signs shall not cover more than 20 percent of the aggregate area of each window facing a public right-of-way. Permanent window signs (except as specified in SMC 18.12.020(A)(7)) shall require review by the DRHPC, and shall be included in the total aggregate sign area allowable for the site. Display of temporary window signage shall not exceed 90 days per year. Illu...
Looking for Sonoma County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Sonoma city rules.
Sign Regulations in Sonoma County →