Zoning Overlays & Bonuses in Sonoma County, CA (2026)

1 county-level rule, 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.

Density Bonus Law

Sonoma County's supplemental density bonus lets a residential project of five (5) or more base units build up to fifty percent (50%) above the maximum density the General Plan and zone district allow. The project must reserve a qualifying share of its base units for lower-income households, starting at 10 percent for extremely low-income households, and the bonus is approved only together with a development permit.

Sonoma County Supplemental Density Bonus Program

Some Restrictions

Sonoma County Code § 26-89-050(D)

County supplemental density bonus program. 1. In addition to the incentives provided by Section 26-89-060 (Affordable Housing Incentives), a residential project of five (5) or more base units shall be eligible for a density bonus of up to fifty percent (50%) above the maximum density allowed by the General Plan and zone district, if the project provides a total of: a. Ten percent (10%) or more ...

Full ordinance details →Official source ↗

Zoning Overlays & Bonuses by City in Sonoma County

2 cities in Sonoma County have their own zoning overlays & bonuses rules. Each link goes to that city's dedicated page with code citations.

Santa RosaPop. 178,127

2 verified rules • Density Bonus Law, Downtown Design Guide

PetalumaPop. 59,776

2 verified rules • Density Bonus Law, Downtown Design Guide

All Sonoma County ordinances

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