Sonoma County — Zoning

Last reviewed: July 6, 2026

Overview

This page explains how zoning works in unincorporated Sonoma County under Chapter 26 — Sonoma County Zoning Regulations. Zoning assigns every parcel a base district and, often, one or more combining (overlay) districts that add special rules. The official zoning database controls boundaries; always verify the mapped designations for a specific site before relying on generalized standards.

In unincorporated areas, a project must conform to the mapped base district, any combining districts, and applicable development standards; permits inconsistent with the General Plan cannot be issued, except that accessory dwelling units are exempt from General Plan density limits. See § 26-02-040(a).

Use this page alongside the Sonoma County zoning & planning overview, Sonoma County Land Use, Sonoma County Development Standards, Sonoma County Parking, Sonoma County Design Review, Sonoma County Overlay Districts, Sonoma County Nonconforming Uses, and Sonoma County Variances and Exceptions.

How Sonoma County zoning is organized

• The zoning regulations are in Chapter 26 — Sonoma County Zoning Regulations. The ordinance defines base districts, combining districts, and how they apply in unincorporated areas.
• The County lists all base districts (e.g., R1, RR, LIA, C2, M1, PF) and combining districts (e.g., F1, F2, SR, B6/B7/B8). The Board may apply other districts case-by-case when appropriate.
• The official zoning “map” is an electronic zoning database maintained by Permit Sonoma. It controls designations and is the reference for property-specific zoning. Boundary questions are resolved by the Board.
• Development must be consistent with the General Plan; no ministerial or discretionary permit may be issued if inconsistent, except ADUs are exempt from the Plan’s density limits under § 26-02-040(a) (coordinate with California ADU law).

Base Zoning Districts (unincorporated areas)

Below is a district-by-district snapshot. For parcel-specific determinations (uses, minimum lot size, setbacks, coverage, height), verify the mapped district and consult the referenced sections. Many dimensional rules (e.g., front-facing garage setbacks, setback projections) apply across multiple zones and are summarized later in a table.

LIA — Land Intensive Agriculture

• Purpose: Agricultural production areas that support intensive cultivation (purpose stated in § 26-04-005).
• Typical permitted uses: Agricultural production and closely related support uses (see agricultural/resource use tables in Article 06, including the general “Allowed Land Uses” framework in § 26-6-030).
• Key dimensional/operational standards that often apply: Front-facing garage/carport minimum 20 ft, setback projections allowed, average-front-setback relief, accessory buildings location rules (see § 26-16-060(C)–(F)). Indoor crop cultivation area caps may apply (e.g., greenhouse area limit 2,500 sq ft in LIA; see § 26-18-160(C)(1)).
• Where it applies: As mapped in the official zoning database; verify for the parcel.

LEA — Land Extensive Agriculture

• Purpose: Agricultural lands where production occurs at lower intensity (purpose in § 26-06-005).
• Typical permitted uses: Agriculture and resource uses per Article 06 tables (§ 26-6-030).
• Key standards: Countywide setback rules commonly apply (see § 26-16-060(C)–(F)). Some agricultural and community facilities in LEA must remain incidental to primary ag production (e.g., community meeting facility criteria in § 26-22-050(B)(3)–(4)).
• Where it applies: Verify via official zoning database.

DA — Diverse Agriculture

• Purpose: Areas with diverse crop and livestock operations (purpose in § 26-08-005).
• Typical permitted uses: Agriculture and related support uses per Article 06 tables (§ 26-6-030).
• Key standards: Setback/garage rules often apply (§ 26-16-060(C)–(F)). Some ag-related processing must not exceed on-site needs (e.g., fertilizer plant size and findings, § 26-20-030(B)(2), (C)).
• Where it applies: Verify mapping in the official database.

RRD — Resources and Rural Development

• Purpose: Resource lands emphasizing conservation and low-intensity development (purpose in § 26-10-005).
• Typical permitted uses: Resource management, low-intensity ag/forestry (see Article 06 tables, § 26-6-030). Incidental land/resource management is regulated in § 26-18-170.
• Key standards: Setback/garage rules often apply in RRD (§ 26-16-060(C)–(F)).
• Where it applies: Check the official database.

TP — Timberland Production Zone

• Purpose: Timber production lands (purpose in § 26-14-005).
• Typical permitted uses: Timber production and closely related uses; certain incidental recreational/educational uses may be recognized in resource/land management standards (see § 26-18-170(A)(1), (B) for related guidance).
• Key standards: Verify parcel-specific limitations in the district article; general yard rules may apply depending on mapped combining districts. Not found in retrieved materials for TP-specific dimensional standards.
• Where it applies: Verify via official database.

AR — Agriculture and Residential

• Purpose: Mix of agricultural and residential uses in a rural setting (purpose in § 26-16-005).
• Typical permitted uses: Residential and small-scale agriculture; see allowed uses table (cross-referenced in § 26-16-010).
• Key standards: Common rules on garages/setbacks/accessory buildings/pools apply in AR (§ 26-16-060(C)–(G)). Agricultural buffers may be required for non-ag uses next to AR lands (§ 26-16-060(H) referencing § 26-88-040(f)).
• Where it applies: Verify mapping.

RR — Rural Residential

• Purpose: Larger-lot residential areas with rural character (purpose in § 26-18-005).
• Typical permitted uses: Residential and certain rural/ag accessory uses; see permitted uses (cross-referenced in § 26-18-010).
• Key standards: Countywide setback/garage rules apply in RR (§ 26-16-060(C)–(G)). Lot coverage waivers may apply to greenhouses (§ 26-16-050(B)(1)).
• Where it applies: Verify mapping.

R1 — Low Density Residential

• Purpose: Low-density single-family neighborhoods (purpose cross-referenced in § 26-20-005; note: Article numbering for R1 has changed over time).
• Typical permitted uses: Detached homes and compatible uses; see permitted uses (cross-referenced in § 26-20-010). Cottage housing: in R1, up to three cottages may be allowed by right; four or more require a use permit (see § 26-88-063).
• Key standards: Common garage/setback rules apply (§ 26-16-060(C)–(G)). Coverage waivers may apply to swimming pools (§ 26-16-050(B)(2)).
• Where it applies: Verify mapping and current article references in the official database.

R2 — Medium Density Residential

• Purpose: Medium-density residential areas (purpose in § 26-22-005).
• Typical permitted uses: Duplexes and similar; see permitted uses (cross-referenced in § 26-22-010). Cottage housing standards also reference R2 (see § 26-88-063).
• Key standards: Common garage/setback rules apply (§ 26-16-060(C)–(G)).
• Where it applies: Verify mapping.

R3 — High Density Residential

• Purpose: Higher-density residential (purpose in § 26-24-005).
• Typical permitted uses: Multi-family residential; see permitted uses (cross-referenced in § 26-24-010). Farmworker housing standards appear elsewhere and can interact with higher-density contexts (§ 26-24-120).
• Key standards: Verify R3-specific dimensional standards; general setback/garage rules may apply where listed. Not found in retrieved materials for R3-specific dimensional metrics.
• Where it applies: Verify mapping.

CO — Administrative and Professional Office

• Purpose: Office uses; mapped within commercial categories (see Article 01 table, CO under General/Limited Commercial).
• Typical permitted uses: Offices and compatible commercial services per the CO article. Not found in retrieved materials for CO permitted-use table.
• Key standards: Height may be increased with a use permit in commercial zones, subject to intensity caps (§ 26-16-030(B) as referenced; see height/use-permit language in § 26-16-030 cross-references). Not found in retrieved materials for CO-specific dimensional metrics.
• Where it applies: Verify mapping.

C1 — Neighborhood Commercial

• Purpose: Local-serving retail and services; see commercial mapping in Article 01.
• Typical permitted uses: Neighborhood retail/service per C1 article. Not found in retrieved materials for C1 permitted-use table.
• Key standards: Potential height increases by use permit apply to commercial zones (§ 26-16-030(B) referenced). General setback projection/average-front-setback rules may apply where listed.
• Where it applies: Verify mapping.

C2 — Retail Business

• Purpose: Community/regional retail. See Article 01 mapping.
• Typical permitted uses: Retail, restaurants, services per C2 article. Not found in retrieved materials for C2 permitted-use table.
• Key standards: Commercial height increases via use permit may apply (§ 26-16-030(B) referenced).
• Where it applies: Verify mapping.

C3 — Heavy Commercial (General Commercial)

• Purpose: More intensive commercial, often auto-oriented. See Article 01 mapping.
• Typical permitted uses: Intensive retail/services per C3 article. Not found in retrieved materials for C3 permitted-use table.
• Key standards: Verify C3-specific metrics; general setback-projection/average-front-setback relief may apply where listed in § 26-16-060(D)–(E).
• Where it applies: Verify mapping.

LC — Limited Commercial

• Purpose: Low-intensity commercial in limited settings. See Article 01 mapping.
• Typical permitted uses: Limited commercial per LC article. Not found in retrieved materials for LC permitted-use table.
• Key standards: Verify LC-specific metrics; general rules may apply as listed in § 26-16-060(D)–(E).
• Where it applies: Verify mapping.

CR — Commercial Rural

• Purpose: Rural-serving commercial uses outside urban service areas. See Article 01 mapping.
• Typical permitted uses: Rural retail/services per CR article. Not found in retrieved materials for CR permitted-use table.
• Key standards: Setback projection and average-front-setback adjustments apply in CR (§ 26-16-060(D), (E)).
• Where it applies: Verify mapping.

K — Recreation and Visitor-Serving Commercial

• Purpose: Recreation and visitor services. See Article 01 mapping.
• Typical permitted uses: Visitor-serving commercial per K article. Not found in retrieved materials for K permitted-use table.
• Key standards: Front-facing garage minimum 20 ft also listed to apply in K (§ 26-16-060(C)(1)). Average-front-setback relief listed for K (§ 26-16-060(E)).
• Where it applies: Verify mapping.

AS — Agricultural Services

• Purpose: Services supporting agriculture. See Article 01 mapping (AS appears under Limited Commercial/Limited Commercial – Traffic Sensitive).
• Typical permitted uses: Ag-support services; fertilizer plants and similar uses must serve local ag production (§ 26-20-030(B)(1)).
• Key standards: Verify AS-specific dimensional standards; general rules as applicable. Not found in retrieved materials for AS dimensional metrics.
• Where it applies: Verify mapping.

MP — Industrial Park

• Purpose: Planned industrial campuses/parks. See Article 01 mapping.
• Typical permitted uses: Light to general industrial, research and development; see lab/manufacturing standards in Article 20 (e.g., labs § 26-20-040, light manufacturing § 26-20-070).
• Key standards: Height may be increased by use permit in industrial zones (§ 26-16-030(B) referenced). Not found in retrieved materials for MP-specific dimensional metrics.
• Where it applies: Verify mapping.

M1 — Limited Urban Industrial

• Purpose: Urban-compatible industrial. See Article 01 mapping.
• Typical permitted uses: Light/medium manufacturing; see Article 20 (e.g., medium manufacturing § 26-20-080; heavy manufacturing in other districts § 26-20-060).
• Key standards: Potential height increases via use permit in industrial zones (§ 26-16-030(B) referenced).
• Where it applies: Verify mapping.

M2 — Heavy Industrial

• Purpose: Higher-intensity industrial uses. See Article 01 mapping.
• Typical permitted uses: Heavy manufacturing/processing (§ 26-20-060).
• Key standards: Verify dimensional metrics; height increase via use permit may apply (§ 26-16-030(B) referenced).
• Where it applies: Verify mapping.

M3 — Limited Rural Industrial

• Purpose: Rural-siting industrial uses. See Article 01 mapping.
• Typical permitted uses: Rural-compatible industry per M3 article. Not found in retrieved materials for M3 permitted-use table.
• Key standards: Verify M3 dimensional metrics; general rules apply as listed. Not found in retrieved materials for M3 dimensional metrics.
• Where it applies: Verify mapping.

PC — Planned Community

• Purpose: Master-planned mixed districts; see Article 01 mapping and PC planning procedures (§§ 26-26-010, 26-26-020, 26-26-050 cross-references).
• Typical permitted uses: Defined through PC preliminary/precise development plans; see development criteria (§ 26-26-060 referenced) and related standards (§ 26-52-050).
• Key standards: Established through the adopted PC plan, with County development criteria. Verify via the PC approvals on record.
• Where it applies: Verify mapping and the applicable PC plan file.

PF — Public Facilities

• Purpose: Public and quasi-public uses. See Article 01 mapping.
• Typical permitted uses: Governmental facilities; see § 26-52-030(a) and related PF standards.
• Key standards: Front-facing garages/carports in PF must observe the 20 ft rule where applicable (§ 26-16-060(C)(1)).
• Where it applies: Verify mapping.

P — Parking District

• Purpose: Off-street parking areas and facilities. Base district listed in § 26-02-090; detailed use/standards not found in retrieved materials.
• Typical permitted uses: Not found in retrieved materials.
• Key standards: Not found in retrieved materials.
• Where it applies: Verify mapping.

Combining (Overlay) Districts that commonly affect zoning

• The County enumerates combining districts including F1 (Floodway), F2 (Floodplain), AH (Affordable Housing), RE (Renewable Energy), SR (Scenic Resources), RC (Riparian Corridor), BH (Biotic Habitat), VOH (Valley Oak Habitat), HD (Historic), G (Geologic Hazard), MR (Mineral Resource), Z (Second Unit Exclusion), X (Mixed Occupancy), B (B6/B7/B8 density and lot-size controls), and TS (Traffic Sensitive) — each with its own article. Always check mapped overlays.
• Example: The B Combining District sets density/lot-size controls; B6 sets a maximum density, and B7/B8 “freeze” lots against further subdivision, with details in § 26-78-005 and § 26-78-010.
• Historic resources may trigger additional review under the HD overlay; coordinate early with Sonoma County Historic Preservation.

Countywide dimensional rules that often control in multiple zones

These apply across many base districts (as listed in the code row for each rule). Always verify the parcel’s district is included in the rule’s applicability list.

Related requirements you may need: parking is codified at § 26-16-070; some projects must go through design review.

Selected use-specific standards that frequently arise

• Cottage Housing in R1/R2: Up to three cottages are allowed by right; four or more require a use permit; lot size and other siting rules apply (§ 26-88-063).
• Farmworker Housing: One unit per qualifying ag operation, with thresholds for crop/livestock scales and groundwater limits in water-scarce areas (§ 26-24-120).
• Indoor Crop Cultivation: Zone-specific greenhouse size caps (e.g., 2,500 sq ft total in LIA/LEA/DA; 800 sq ft in RR), and use-permit thresholds in resource zones (§ 26-18-160).
• Land & Resource Management: Often must be incidental to primary use in ag/resource zones; TP and RRD have specific allowances and limits (§ 26-18-170).

Zoning map and how to read it

• The County’s “official zoning map” is an electronic database. It shows the base district and any combining districts for each parcel. For uncertain boundaries, the Board determines the line. Reference § 26-02-110, § 26-02-120, and § 26-02-130.
• Zoning must be consistent with the General Plan land use categories (see mapping table in Article 01). Use the Article 01 table to understand which base districts typically implement each Plan designation.

Checklist

• Confirm the parcel is in the unincorporated area (County zoning does not govern incorporated cities).
• Look up the parcel’s base district and combining districts in the official zoning database (map).
• Identify the applicable General Plan land use category and ensure use/intensity align; note that ADUs are exempt from GP density limits.
• Check the district’s permitted and use-permit tables for your proposed use (Articles 06–26 as applicable; e.g., § 26-16-010, § 26-18-010).
• Apply countywide development standards (setbacks, projections, accessory buildings, pools, coverage) where listed for your zone.
• Screen for combining districts (e.g., B6/B7/B8, SR, RC, HD) and apply overlay-specific rules.
• Check if design review applies due to location, use, or overlay.
• Confirm parking ratios and design under § 26-16-070.
• If the site has existing non-standard conditions, read Nonconforming Uses.
• If strict application of a standard creates hardship, evaluate a variance or exception.

Risks & Ambiguities

Plain-English Summary

In unincorporated Sonoma County, every parcel has a base zoning district (like R1, RR, LIA) and sometimes overlays (like B6 or scenic/habitat layers). Your permitted uses come from the district table, and your building envelope comes from countywide standards like setbacks and projections. Always confirm the district(s) in the County’s official zoning database and check any overlays before you design.

Source References

• Chapter 26 — Sonoma County Zoning Regulations; Article 01 mapping of General Plan categories to base districts (e.g., R1, LIA, C2, M1) — § 26-01-010; ordinance purpose/composition — §§ 26-02-010, 26-02-020.
• Base districts enumerated — § 26-02-090; Combining districts enumerated — § 26-02-100; Official zoning database/boundaries — §§ 26-02-110, 26-02-120, 26-02-130.
• Development standards (setbacks, projections, accessory buildings, pools, coverage, parking) — §§ 26-16-050, 26-16-060, 26-16-070.
• Agricultural/resource zone purposes and land use tables — §§ 26-04-005, 26-06-005, 26-08-005, 26-10-005, 26-14-005, 26-6-030.
• Residential zone purposes/permits cross-references — §§ 26-16-005/010 (AR), 26-18-005/010 (RR), 26-20-005/010 (R1), 26-22-005/010 (R2), 26-24-005/010 (R3).
• PC and PF cross-references — §§ 26-26-010, 26-26-020, 26-26-050, 26-26-060, 26-52-030, 26-52-050.
• Use-specific standards: Cottage housing — § 26-88-063; Farmworker housing — § 26-24-120; Indoor crop cultivation — § 26-18-160; Land/resource management — § 26-18-170.
• General Plan consistency; ADU density exemption — § 26-02-040(a).

Information Gaps

• Detailed, district-specific dimensional standards (e.g., minimum lot size, height, setbacks by district) for many districts were not present in the retrieved materials. Not found in retrieved materials.
• Full permitted-use tables for commercial/industrial districts (CO, C1, C2, C3, LC, CR, K, MP, M1, M2, M3) were not present. Not found in retrieved materials.
• PF and P district specific standards not provided. Not found in retrieved materials.

Retrieved passages

• Sonoma County Zoning Code (Section 26.88.063) High relevance show source text
• Sonoma County Zoning Code (Section 26-88-040) High relevance show source text
• Sonoma County Zoning Code (§ III) High relevance show source text
• Sonoma County Zoning Code (§ 4) High relevance show source text
• Sonoma County Zoning Code (§ II) High relevance show source text
• Sonoma County Zoning Code (Section 47050) High relevance show source text
• Sonoma County Zoning Code (§ II) Medium relevance show source text
• Sonoma County Zoning Code (§ 11) Medium relevance show source text

Cited sections

• Chapter 26 — Sonoma County Zoning Regulations; Article 01 mapping of General Plan categories to base districts (e.g., **R1**, **LIA**, **C2**, **M1**) — § 26-01-010; ordinance purpose/composition — **§§ 26-02-010, 26-02-020**. (Chapter 26)
• Base districts enumerated — **§ 26-02-090**; Combining districts enumerated — **§ 26-02-100**; Official zoning database/boundaries — **§§ 26-02-110, 26-02-120, 26-02-130**. (§ 26-02-090)
• Development standards (setbacks, projections, accessory buildings, pools, coverage, parking) — **§§ 26-16-050, 26-16-060, 26-16-070**. (§ 26-16-050)
• Agricultural/resource zone purposes and land use tables — **§§ 26-04-005, 26-06-005, 26-08-005, 26-10-005, 26-14-005, 26-6-030**. (§ 26-04-005)
• Residential zone purposes/permits cross-references — **§§ 26-16-005/010 (AR), 26-18-005/010 (RR), 26-20-005/010 (R1), 26-22-005/010 (R2), 26-24-005/010 (R3)**. (§ 26-16-005)
• PC and PF cross-references — **§§ 26-26-010, 26-26-020, 26-26-050, 26-26-060, 26-52-030, 26-52-050**. (§ 26-26-010)
• Use-specific standards: Cottage housing — **§ 26-88-063**; Farmworker housing — **§ 26-24-120**; Indoor crop cultivation — **§ 26-18-160**; Land/resource management — **§ 26-18-170**. (§ 26-88-063)
• General Plan consistency; ADU density exemption — **§ 26-02-040(a)**. (§ 26-02-040)
• SonomaCounty_ZoningCode.md

• Official Sonoma County code library