Colusa County, CA Building Setbacks & Zoning: Setback Rules (2026)

The Colusa County Zoning Code (Article 44-2) establishes minimum setbacks in development-standards tables that vary by zoning classification. In the residential zones - Rural Residential (R-R), Single-Family (R-1), Two-Family (R-2), Multiple-Family (R-3), and Apartment-Professional (R-4) - the minimum primary-structure setbacks are: front 20 feet (15 feet in R-4); rear 20 feet in R-R and R-1, and 15 feet in R-2, R-3, and R-4; interior side 10 feet in R-R and 6 feet in R-1 through R-4; and street side 10 feet in R-R, 8 feet in the others. Accessory structures have reduced setbacks: front 20 feet, rear 5 feet, street side 10 feet, and interior side 5 feet (in the front half of the lot) or 3 feet (in the rear half), and must stand at least 5 feet from any building. In the agricultural zones, agricultural structures generally require a 20-to-25-foot front setback, a 20-foot rear setback, and a 10-foot side setback, while non-agricultural structures need 25-foot front and rear setbacks and 20-to-25-foot side setbacks. Commercial and industrial zones have their own front, rear, and side standards (some allowing no setback). Setbacks are measured from the property line to the structure, and a 15-foot front setback applies in some commercial zones adjacent to a residential zone. Owners should confirm their parcel's zone with the Planning Division.