Colusa County — Signage

Last reviewed: July 6, 2026

Overview

This page explains what we can confirm (and what we cannot) about sign regulations for properties in the unincorporated areas of Colusa County. Important: the sign chapter retrieved from the materials is the City of Colusa’s ordinance (inside “Appendix A – Zoning”) and repeatedly limits its applicability “to the city.” Those city provisions do not govern unincorporated Colusa County. Where the county’s own signage standards are not available in the retrieved materials, this page flags the gaps and points to next steps to verify with the jurisdiction.

Most critical takeaway: Do not apply the City of Colusa sign rules to parcels in unincorporated Colusa County; the retrieved sign article explicitly applies “within the city,” not the county’s unincorporated areas (§ 31.01; § 1.06).

What the retrieved code actually covers (City of Colusa — not county)

• The retrieved sign article (“Article 31 – Outdoor Advertising and Sign Regulations”) states its purpose and applicability “within the city.” It sets measurement rules (e.g., sign area counts one face if a double-sided sign has less than 18 inches between faces) and allows noncommercial message substitution (§ 31.01). This is city-only.
• Permit triggers and exemptions are also written “situated in the city” (§ 31.02; § 31.03). Again, city-only.
• Prohibited signs (e.g., those blocking fire escapes, interfering with traffic visibility, or painted on exterior walls without approval) are listed in city code (§ 31.04). City-only.
• District-specific city rules appear in commercial/industrial districts, e.g. wall-parallel signs in C‑N capped at 50 sq ft and one sq ft per linear foot of frontage; and larger allowances in C‑G, C‑H, and M/M‑U for attached signs up to two sq ft per frontage foot and a total of 240 sq ft per site (§ 31.03(c)). City-only.
• City districts like C‑H even reference “outdoor advertising signs” with ratios tied to frontage (§ 11.02). City-only.

Because all of the above are expressly “City of Colusa,” they do not govern unincorporated areas. They are cited here solely to show why the retrieved materials cannot be used for county parcels.

County sign rules for unincorporated areas — what’s confirmed and what’s not

• Countywide sign chapter (title/chapter/section numbers) for unincorporated Colusa County: Not found in retrieved materials.
• County definitions, measurement methods, exemptions, prohibited signs, and permit procedures: Not found in retrieved materials.
• County district-by-district sign standards: Not found in retrieved materials.

If you’re working in the unincorporated county, start with the Colusa County Zoning map and code, then confirm whether any Overlay Districts (e.g., corridor/highway, scenic, floodplain) add sign limitations. Expect sign review to tie into site Design Review, Development Standards, and possibly Parking (e.g., monument sign placement near driveways).

District-by-district standards in unincorporated Colusa County

• Not found in retrieved materials. Verify the county’s base districts and any corridor/overlay rules that change maximum area, height, illumination, number, placement, and freeway-facing allowances for signs in the unincorporated areas. Verify with the jurisdiction.

Most decision-relevant items (unincorporated Colusa County)

The table below lists common sign topics and whether we could confirm county-specific standards from the retrieved materials.

For structural and electrical safety of sign installations, the state’s California Building Standards Code may apply (e.g., Appendix H for sign structures), but that is outside zoning; confirm separately with Building. The retrieved Appendix H text is general and not county-specific. If relevant, consult your building official.

Practical guidance for unincorporated-area applicants

• Confirm you are outside incorporated city limits via the county’s Colusa County zoning & planning overview and mapping tools. The retrieved Article 31 and related city sections do not apply to unincorporated parcels (§ 1.06).
• Identify your parcel’s base zoning and any overlays using Colusa County Land Use and Overlay Districts. Overlays can change sign allowances (corridor height, freeway visibility, lighting).
• Ask Planning which sign chapter controls in the unincorporated county and whether your proposal needs Design Review or a sign permit. If your sign deviates, explore Variances and Exceptions.
• If you are altering a lawful-but-nonconforming sign, check Colusa County Nonconforming Uses to avoid losing status.
• Coordinate early on sight-distance, landscaping setbacks, and lighting spill. County sign rules often reference driveway visibility and screening; confirm with Colusa County Landscaping and Screening.

Checklist

• Verify parcel is in the unincorporated county (not within City of Colusa limits).
• Obtain the controlling county sign chapter citation (title/chapter/section) from Planning. Not found in retrieved materials.
• Confirm base zoning and any applicable overlays that modify sign size, height, number, placement, illumination. Not found in retrieved materials.
• Determine whether your sign is exempt, ministerial, or requires discretionary approval. Not found in retrieved materials.
• Confirm measurement rules (how area is calculated, counting faces) and maximums for your frontage(s). Not found in retrieved materials.
• Verify any temporary sign limits (duration, number, per-event windows). Not found in retrieved materials.
• If near state highways/right-of-way, confirm Caltrans encroachment/visibility limits. Verify with the jurisdiction.
• If replacing or modifying an existing sign, confirm nonconforming status and allowable changes.
• Coordinate structural/electrical compliance under building code with Building Division (zoning vs. building are separate processes).

Risks & Ambiguities

Plain-English Summary

If your property is in unincorporated Colusa County, don’t use the City of Colusa sign rules you may find online—the retrieved article clearly applies only “within the city.” The county’s own sign chapter (title/sections) did not appear in the retrieved materials. Call the County Planning Department to confirm the correct chapter, your base zoning, any overlay rules, and the exact limits on sign size, height, lighting, number, and placement for your site.

Information Gaps

• County sign chapter number/title and section-by-section standards: Not found in retrieved materials.
• County exemptions, prohibited signs, measurement rules, and permit thresholds: Not found in retrieved materials.
• County district-by-district signage standards and any corridor/overlay-specific sign rules: Not found in retrieved materials.

Source References

• City of Colusa Zoning Ordinance (City, not county): Article 31 – Outdoor Advertising and Sign Regulations: purpose/applicability, measurement, message substitution (§ 31.01); permits/exemptions (§ 31.02–§ 31.03); prohibited signs (§ 31.04); nonconforming (§ 31.05). City applicability shown throughout (e.g., “situated in the city”).
• City of Colusa Zoning Ordinance: Application limited to incorporated city area (§ 1.06).
• City of Colusa district sign examples (City, not county): § 31.03(c) for C‑N, C‑G, C‑H, M, M‑U allowances; § 11.02 for C‑H frontage-based outdoor advertising.

Retrieved passages

• Colusa County Zoning Code (section shall) High relevance show source text
• Colusa County Zoning Code (section shall) High relevance show source text
• Colusa County Zoning Code (§ 2) High relevance show source text
• Colusa County Zoning Code (section shall) Medium relevance show source text
• Colusa County Zoning Code (article upon) Medium relevance show source text
• CBC § 3 (Section 31.03.c.3) Medium relevance show source text
• California Building Code (Article 32) Medium relevance show source text
• CBC § H101 (SECTION H101) Medium relevance show source text
• Colusa County Zoning Code High relevance show source text
• Colusa County Zoning Code (Title 36) Medium relevance show source text

Cited sections

• City of Colusa Zoning Ordinance (City, not county): Article 31 – Outdoor Advertising and Sign Regulations: purpose/applicability, measurement, message substitution (§ 31.01); permits/exemptions (§ 31.02–§ 31.03); prohibited signs (§ 31.04); nonconforming (§ 31.05). City applicability shown throughout (e.g., “situated in the city”). (Article 31)
• City of Colusa Zoning Ordinance: Application limited to incorporated city area (§ 1.06). (§ 1.06)
• City of Colusa district sign examples (City, not county): § 31.03(c) for C‑N, C‑G, C‑H, M, M‑U allowances; § 11.02 for C‑H frontage-based outdoor advertising. (§ 31.03)
• ColusaCounty_ZoningCode.md

• Official Colusa County code library