Local zoning · Modoc County

Modoc County — Signage

Q: What sizes are allowed for business signs in unincorporated Modoc County commercial areas?

In the C zone (and IL , I , and RT with no dwelling), you may have one freestanding sign per 100 feet of street frontage (32–64 sq ft depending on frontage length) plus building signs up to the greater of 1 sq ft per foot of building frontage or 64 sq ft aggregate. See § 18.110.070(A)(9).

Q: How big can a for-sale sign be on a rural residential lot?

In RR , RL , RH , or RT with a dwelling , each real‑estate sign is limited to 6 sq ft. Elsewhere it’s generally 32 sq ft per sign. See § 18.110.070(A)(4).

Q: Are temporary signs allowed in residential zones?

Yes. One temporary sign per lot is allowed, but in RH , RL , and RR the total temporary sign area may not exceed 4 sq ft. See § 18.110.070(A)(5).

Signage under the Modoc County local zoning and planning code, with the controlling citations.

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Last reviewed: July 6, 2026

Overview

In unincorporated Modoc County, on-site and off-site signs are governed by the county’s zoning ordinance, formally titled Title 18 – Zoning. The county’s primary, countywide sign standards live in § 18.110.070 (Signs), and they apply across all base zoning districts with targeted size and number limits by district type, plus general rules for height, clearance, illumination, animation, maintenance, and right‑of‑way encroachments.

Signs also interact with underlying zoning and overlays. Start by confirming your parcel’s zoning and any overlays on the county’s maps (see the unincorporated-area Modoc County Zoning and Overlay Districts references), then apply the sign standards below.

A “sign” is any visual device and its support intended to communicate a message or attract attention from off-site; devices not visible from off the lot are not “signs” under the ordinance. See § 18.06.900.

What the ordinance regulates countywide (applies in all zones)

Allowed sign types in all zones include noncommercial/official, community identification, private on‑site traffic direction, for‑sale/lease, temporary, construction site identification, accessory residential, limited home occupation nameplates, and appurtenant business signs, with zone‑specific size/number caps in § 18.110.070(A). Off‑site “nonappurtenant” signs are also recognized (subject to the California Outdoor Advertising Act). See § 18.110.070(A).
Number of signs: how to count one sign vs. multiple sign faces is specified in § 18.110.070(B).
Exceeding size/number: can be considered with a use permit under § 18.110.070(C).
Height: freestanding signs cannot exceed the zone’s maximum building height; wall signs cannot extend above the roofline per § 18.110.070(I).
Illumination and color: avoid glare and avoid colors/placements that could be confused with traffic control devices under § 18.110.070(G)–(H).
Movement and special effects: blinking, flashing, rotating, animated, or color‑changing signs are prohibited, except to display time/date/weather under § 18.110.070(F).
Rights‑of‑way and clearances: a minimum 8 ft clearance for projecting/freestanding signs; no sign over or in a public right‑of‑way without an encroachment permit; special 12‑ft clearances for any sign/lighting within a right‑of‑way under § 18.110.070(J)–(K).
Lots without street frontage: limited ability to place a nonappurtenant sign on the access street’s frontage per § 18.110.070(E).
Maintenance: signs must remain safe and readable; once 20%+ of a face is missing/indistinguishable, it is “unreadable” under § 18.110.070(L).

For project‑level site planning, coordinate sign placement with your Development Standards and any Parking layouts, and confirm if your jurisdiction requires Design Review. Structural/electrical safety for sign construction is under the California Building Standards Code, not the zoning ordinance.

Quick reference — common sign types and countywide limits

Sign Type	Core Allowance (countywide)	Key Notes	Code Reference
Noncommercial/official (e.g., flags, public-utility notices, political/religious messages)	Not regulated by Title 18 if noncommercial and limited per ordinance	One per abutting street; each up to 16 sq ft for noncommercial messages	§ 18.110.070(A)(1)
Community identification (near city/county boundaries)	Up to 4 per community; each up to 64 sq ft	Not allowed where location is zoned RH, RL, RR	§ 18.110.070(A)(2)
Private on-site traffic direction	Up to 4 sq ft; no advertising matter	On private property only	§ 18.110.070(A)(3)
Real estate (sale/lease/rent)	One per abutting street + one per 200 lf frontage; each up to 32 sq ft	In RH, RL, RR, or RT with a dwelling: each max 6 sq ft; plus one on-site and one off-site per five lots	§ 18.110.070(A)(4)
Temporary	One per lot; up to 32 sq ft	In RH, RL, RR: total temporary sign area max 4 sq ft	§ 18.110.070(A)(5)
Construction site identification	One per abutting street + one per 200 lf lot line; each up to 32 sq ft	Only during active construction; remove within 15 days of final occupancy	§ 18.110.070(A)(6)
Accessory residential	Customary to residential use; each up to 4 sq ft	In RH, RL, RR: aggregate up to 16 sq ft; subdivision/multifamily entrance ID up to 32 sq ft per entrance	§ 18.110.070(A)(7)
Home occupation	One nameplate, 6 in by 12 in, flush-mounted	No use permit/variance may increase this limit	§ 18.110.070(A)(8)
Appurtenant business signs in C, IL, I, and RT (no dwelling)	Freestanding: one per 100 lf of frontage (32–64 sq ft depending on frontage length); Building signs: greater of 1 sq ft per lf of building frontage or 64 sq ft total	Applies to shopping centers/multi-tenant sites	§ 18.110.070(A)(9)
Appurtenant signs in all other zones	One per abutting street; up to 32 sq ft	If lot abuts >400 lf, one sign per 400‑ft segment	§ 18.110.070(A)(10)
Communications facilities/towers	Limited to address/facility ID and safety; typical max 12 in x 24 in facility ID	Larger only if required by FCC/other regulator with proof	§ 18.166.050(C)(6)

District-by-district sign allowances (unincorporated areas)

The table above applies across all zones; below are zone‑by‑zone notes emphasizing which line(s) of § 18.110.070(A) typically govern, plus other sign‑related constraints. For base zone purposes and non‑sign standards, see Modoc County Land Use and Modoc County Development Standards.

TP — Timberland Production

Purpose/typical uses: Not found in retrieved materials.
Appurtenant signs: Treated as “all other zones”—one per abutting street, up to 32 sq ft; one per each 400‑ft segment if applicable (see § 18.110.070(A)(10)).
Real estate/temp signs: Typically up to 32 sq ft; see countywide table.
Height/clearance/illumination/movement: Countywide rules apply (§ 18.110.070(F)–(K)).

OFG — Open Space, Forestry and Grazing

Purpose/typical uses: Not found in retrieved materials.
Appurtenant signs: “All other zones” rule—one per abutting street, up to 32 sq ft (§ 18.110.070(A)(10)).
Other standards: Countywide rules as above.

RC — Resource Conservation

Purpose/typical uses: Not found in retrieved materials.
Signs: Same “all other zones” rule (§ 18.110.070(A)(10)).

AE — Agricultural Exclusive

Purpose/typical uses: Not found in retrieved materials.
Signs: “All other zones” rule (§ 18.110.070(A)(10)). Real estate/temp signs up to 32 sq ft per countywide table.

LIC — Low Intensity Conservation

Purpose/typical uses: Not found in retrieved materials.
Signs: “All other zones” rule (§ 18.110.070(A)(10)).

AG — Agricultural General

Purpose/typical uses: Not found in retrieved materials.
Signs: “All other zones” rule (§ 18.110.070(A)(10)).

LI — Low Intensity

Purpose/typical uses: Not found in retrieved materials.
Signs: “All other zones” rule (§ 18.110.070(A)(10)).

RR — Rural Residential

Purpose/typical uses: Single‑family, rural residential context (development standards point to Ch. 18.110 for signs). § 18.30.060(D).
Residential accessory signs: Each up to 4 sq ft, with 16 sq ft aggregate allowed in RR (§ 18.110.070(A)(7)). Subdivision/multifamily entrance ID up to 32 sq ft at each entrance.
Real estate: Max 6 sq ft per sign in RR (§ 18.110.070(A)(4)). Temporary: 4 sq ft total in RR (§ 18.110.070(A)(5)).
Height/clearance/illumination/movement: Countywide rules apply (§ 18.110.070(F)–(K)).

RL — Residential Low Density

Purpose/typical uses: Not found in retrieved materials.
Residential accessory, real estate, and temporary signs: Same as RR (see above) under § 18.110.070(A)(4)–(5), (7).

RH — Residential High Density

Purpose/typical uses: Not found in retrieved materials.
Residential accessory, real estate, and temporary signs: Same as RR/RL. § 18.110.070(A)(4)–(5), (7).

RT — Rural Town

With a dwelling: Real estate signs max 6 sq ft; temporary signs 4 sq ft total (treated like residential caps). § 18.110.070(A)(4)–(5).
With no dwelling (commercialized RT frontage): Use the commercial/industrial rule—freestanding and building sign allowances per § 18.110.070(A)(9).
Home occupation: Single 6‑in x 12‑in flush nameplate only (§ 18.110.070(A)(8)).

C — Commercial

Appurtenant business signs: Freestanding one per 100 lf of frontage (32–64 sq ft depending on length) and building signs up to the greater of 1 sq ft/lf of building frontage or 64 sq ft; multi‑tenant centers included (§ 18.110.070(A)(9)).
General rules on movement, lighting, height, clearance apply; see § 18.110.070(F)–(K).

IL — Industrial Light

Same allowances as C under § 18.110.070(A)(9).

I — Industrial

Same allowances as C under § 18.110.070(A)(9).

PD — Planned Development

Purpose/typical uses: Not found in retrieved materials.
Signs: Unless otherwise established through PD approvals, use the “all other zones” rule (§ 18.110.070(A)(10)) or the applicable underlying base zone’s rule; verify with the jurisdiction.

PF — Public Facilities

Purpose/typical uses: Not found in retrieved materials.
Signs: Generally fall under the “all other zones” allowance in § 18.110.070(A)(10) unless a facility is developed to commercial standards. Verify with the jurisdiction.

U — Unclassified

Purpose/typical uses: Not found in retrieved materials.
Signs: Apply the “all other zones” rule (§ 18.110.070(A)(10)) pending further entitlement.

Special topics and overlays that affect signage

Nonappurtenant (off‑site) signs: Recognized and subject to other regulations under the California Outdoor Advertising Act; check state compliance in addition to county rules in § 18.110.070(A).
Airport Hazard (AH) overlay: Airport hazard regulations can impose more stringent height/lighting conditions that supersede general limits; where rules conflict, the stricter standard applies per § 18.90.150. Verify sign height against the underlying zone’s building height rule in § 18.110.070(I) and confirm any AH constraints with the County.
Communications facilities: Signage at towers/facilities is tightly limited to small facility identification and safety information under § 18.166.050(C)(6).
Historic contexts: Sign‑specific standards were not found; see Modoc County Historic Preservation and verify if separate criteria apply. Not found in retrieved materials.

For legal nonconforming signs and potential changes, see Modoc County Nonconforming Uses. If you need relief beyond these standards, explore Modoc County Variances and Exceptions or the use‑permit pathway in § 18.110.070(C).

Checklist

Confirm your parcel is in the unincorporated area and identify the base zone and any overlays (AH, etc.) using county zoning maps.
Determine if your sign is appurtenant (on‑site) or nonappurtenant (off‑site) per § 18.06.910/§ 18.06.940.
Choose the allowed sign type and match zone‑specific size/number caps in § 18.110.070(A).
For commercial/industrial or RT (no dwelling), calculate freestanding and building sign allowances under § 18.110.070(A)(9); for other zones use § 18.110.070(A)(10).
Check illumination, color, animation bans, and glare control in § 18.110.070(F)–(H).
Verify sign height versus your zone’s maximum building height under § 18.110.070(I) and any overlay constraints.
Ensure clearance and right‑of‑way compliance, including any encroachment permit needs under § 18.110.070(J)–(K).
If exceeding size/number, pursue a use permit per § 18.110.070(C).
For communications facilities, limit signage per § 18.166.050(C)(6).
Coordinate with Design Review if required, and remember structural/electrical safety is under the California Building Standards Code.

Risks & Ambiguities

Issue	Why it matters	What to verify
Off‑site “billboards” vs. on‑site appurtenant signs	Nonappurtenant signs trigger additional state law compliance	Whether your sign is “nonappurtenant” under § 18.06.940 and the California Outdoor Advertising Act; local allowances in § 18.110.070(A).
Multi‑tenant centers (C/IL/I/RT no dwelling)	Aggregate building sign area is limited	Building frontage measurement and total building sign area under § 18.110.070(A)(9).
Lots without street frontage	May need off‑site placement	Eligibility to allocate permitted area to a nonappurtenant sign along the access street under § 18.110.070(E).
Right‑of‑way encroachments	Prohibited without a permit; special clearance applies	Need for an encroachment permit and 12‑ft clearance for anything within a right‑of‑way per § 18.110.070(K).
Height in overlay areas (e.g., Airport Hazard)	More stringent limits can control	Whether an overlay applies and if its restrictions supersede general standards per § 18.90.150; apply § 18.110.070(I) for freestanding sign height.
Illumination colors/placement	Avoid traffic-signal confusion/glare	Lighting color/aiming under § 18.110.070(G)–(H).
Maintenance threshold	Unreadable signs can be cited	The 20% unreadable standard in § 18.110.070(L).

Plain-English Summary

If your property is in unincorporated Modoc County, the county lets you post certain on‑site signs by right and sets size/number caps by zone. Residential zones allow small nameplates and modest temporary/real‑estate signs; commercial and industrial zones (and RT without a dwelling) allow larger freestanding and building signs tied to frontage, but still prohibit flashing/animated signs and limit height to your zone’s building height. For anything bigger than the base limits, you’ll need a use permit—and if your sign is off‑site, you must also meet state billboard rules. See § 18.110.070.

Source References

Title 18 – Zoning; Zoning districts established; unincorporated applicability: § 18.02.030–.040.
Definitions: “Sign,” “Appurtenant sign,” “Freestanding sign,” “Nonappurtenant sign”: § 18.06.900–.940.
Countywide sign standards (types, counting, use permit to exceed, lot w/o frontage, animation, lighting, height, clearance/ROW, maintenance): § 18.110.070(A)–(L).
Rural Residential development standards (reference to Ch. 18.110 for signs): § 18.30.060(D).
Communications facilities signage limits: § 18.166.050(C)(6).
Airport Hazard chapter (conflicts/stricter rule applies): § 18.90.150.
Related topics: Modoc County zoning & planning overview, Modoc County Zoning, Modoc County Land Use, Modoc County Development Standards, Modoc County Design Review, Modoc County Overlay Districts, Modoc County Nonconforming Uses, Modoc County Variances and Exceptions, California Building Standards Code

Sources

Retrieved passages

Modoc County Zoning Code (Chapter 12.04) High relevance
CBC § 11362.5 (Chapter 18.170) High relevance
Modoc County Zoning Code (title or) Medium relevance
Modoc County Zoning Code (section may) Medium relevance
Modoc County Zoning Code Medium relevance
Modoc County Zoning Code (Chapter 18.170) Medium relevance
Modoc County Zoning Code (section may) Medium relevance
CEC § H103 (SECTION H103) Medium relevance

Cited sections

Official Modoc County code library

Frequently asked questions

What sizes are allowed for business signs in unincorporated Modoc County commercial areas?

In the C zone (and IL, I, and RT with no dwelling), you may have one freestanding sign per 100 feet of street frontage (32–64 sq ft depending on frontage length) plus building signs up to the greater of 1 sq ft per foot of building frontage or 64 sq ft aggregate. See § 18.110.070(A)(9).

How big can a for-sale sign be on a rural residential lot?

In RR, RL, RH, or RT with a dwelling, each real‑estate sign is limited to 6 sq ft. Elsewhere it’s generally 32 sq ft per sign. See § 18.110.070(A)(4).

Are temporary signs allowed in residential zones?

Yes. One temporary sign per lot is allowed, but in RH, RL, and RR the total temporary sign area may not exceed 4 sq ft. See § 18.110.070(A)(5).

Can I put a sign in or over the county road right‑of‑way?

Not without an encroachment permit. There are also minimum 12‑ft clearance rules for any sign or floodlight within a right‑of‑way and 8‑ft clearance for projecting/freestanding signs. See § 18.110.070(J)–(K).

Are flashing or animated LED signs allowed?

No. Blinking, flashing, rotating, animated, or color‑changing signs are prohibited, except to display time, date, and weather information. See § 18.110.070(F).

How tall can a freestanding sign be?

Freestanding signs cannot exceed the maximum building height allowed in the zone where the sign is located, and wall signs may not extend above the roofline. See § 18.110.070(I).

I don’t have street frontage. Can I place a sign by the access road?

Possibly. A portion of your permitted sign area can be allocated to one nonappurtenant sign along each access street frontage (not in RH, RL, RR) if conditions in § 18.110.070(E) are met.

Do communication towers get typical business signs?

No. Tower signage is limited to address/facility identification and safety notices; a small, weatherproof ID sign (often 12 in x 24 in) is standard unless a regulator requires larger, with proof. See § 18.166.050(C)(6).

Can I get approval for a larger sign than the base limits?

Yes, if you secure a use permit. The county may allow signs exceeding number/size criteria under § 18.110.070(C).

Do overlay zones like Airport Hazard change sign rules?

They can. The stricter rule controls where there’s a conflict, so verify any AH overlay constraints against your zone and § 18.110.070(I). See § 18.90.150.

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