Summary of Sign Regulations

The following guidelines summarize the detailed provisions of the City's Sign Ordinance (Sonoma Municipal Code, Title 18). Copies of the Sign Ordinance are available at City Hall.

Number of Signs

Normally, each business may have up to two signs. Additional signs may be allowed at the discretion of the Architectural Review Commission, per the regulations of the Sign Ordinance.

Aggregate Sign Area

The maximum allowable sign area for any building in a commercial or mixed-use zone is based on public street frontage. The maximum aggregate area which may be applied for is calculated as follows: 1) Primary Street Frontage: for the first thirty feet of primary street frontage frontage, the allowable sign area is three square feet for every five lineal feet of frontage. For primary frontage in excess of thirty feet, an additional two square feet of sign area for every five feet of frontage may be permitted. 2) Secondary Frontage: one square foot of sign area may be allowed for every five lineal feet of secondary frontage.

Maximum Size

No sign may exceed 48 square feet in area. Interior illuminated signs may not exceed 27 square feet in area and exterior illuminated signs may not exceed 32 square feet in area. Each face of a double-sided interior illuminated sign may not exceed 18 square feet in area and each face of a double-sided exterior illuminated sign may not exceed 21 square feet in area. In calculating the aggregate area of a dou- ble-sided sign, each face shall be multiplied by 0.75.

Neon Signs

In commercial zones, neon signs of less than two-square feet in area may be allowed with design review, subject to a limit of one such sign per business.

A-Board Signs

Subject to the review and approval of the Architectural Review Commission, one A-board sign per business may be allowed, of a maximum height of four feet and a maximum width of two feet. The sign must be placed in front of the business which it advertises and may only stand during business hours. The sign must be placed so as not to block pedestrian traffic or present a hazard (a minimum sidewalk clearance of 48” is required). A-board signs do not count against the number or aggregate area of signs allowed for a business under the Sign Ordinance.

Administrative Review

Over the counter review is possible for certain sign applications, including the replacement of existing conforming signs, new wall signs of 10 square feet in area or less and new hanging or projecting signs of 6 square feet or less (per side). Some limitations apply, as follows: a) no more than two signs per business, b) the lettering of informational text may not exceed 4 inches in height; c) new illuminated signs, new signs in residential zones, new multi-tenant sign programs, new roof signs or freestanding signs, variances to the Sign Ordinance, and the replacement of interior illuminated signs are not subject to administrative review.


All signs subject to a permit shall be installed and maintained in a manner consistent with the pro- visions of the City’s Sign Ordinance, including the Sign Design Guidelines.


Plaza Periphery Wayfinding Signage Program