Local zoning · San Mateo

San Mateo — Signage

Q: Do I need a planning application for a freestanding sign in San Mateo?

If the sign is part of a planned signing district or a freestanding sign over 8 feet in a commercial district you must file a Planning Application (PA) under § 27.08.010(a)(13). Always confirm with the Planning Division because overlays or specific plans can add additional requirements.

Q: Can an open‑air vendor in San Mateo use illuminated signage?

No — Title 27 specifically limits open air vendor signs to non‑electrical signs permanently affixed to the vendor’s conveyance with total area not to exceed 6 square feet (§ 27.67.060(f)). Illuminated signs are therefore not allowed for these vendors under that rule.

Signage under the San Mateo local zoning and planning code, with the controlling citations.

Ask a question free See coverage

Last reviewed: July 2, 2026

Overview

San Mateo’s Title 27 zoning code contains limited, use‑specific sign rules and several cross‑references that defer the technical sign standards to a separate sign code. Title 27 establishes where signs are allowed as part of permitted uses, sets small‑use size caps (recycling machines, open‑air vendors), requires planning review for large or freestanding signs, and repeatedly requires that exterior signs “pertain only to a use conducted within the building.” For full technical standards (area, height, illumination, classifications) Title 27 repeatedly points to the City’s sign regulations in Title 25 (see the specific § citations below). See the City zoning menu at San Mateo Zoning for context.

Notes up front:

Where Title 27 is silent about size/height/illumination it either defers to Title 25 or to the building code for structural/electrical rules; verify Title 25 for permitting thresholds.
When a project triggers Site Plan & Architectural Review or other planning approvals, follow the SPAR procedures under design review.

(First mentions of related topics — parking, development standards, design review, overlay districts, ADUs, and the state building code — are linked for quick navigation: San Mateo Parking, San Mateo Development Standards, San Mateo Design Review, San Mateo Overlay Districts, San Mateo ADUs, and California Building Standards Code.)

How Title 27 treats signage (key rules)

Title 27 contains several narrow, use‑specific sign standards (caps for recycling containers and open‑air vendors) and repeated policy language that exterior signs must relate to on‑site uses; it does not contain a comprehensive sign schedule (area, height, illumination) — the code delegates that detail to Title 25. See § 27.69.030, § 27.67.060(f), and § 27.38.020(c).
Large freestanding signs and the establishment of “planned signing districts” are treated as planning applications and require a Planning Application (PA) per § 27.08.010(a)(13); the Zoning Administrator also has authority over freestanding signs in some approvals.
Many commercial‑district “conditions of use” include the rule that any exterior sign must pertain only to a use conducted on the premises (for example § 27.32.030(c), § 27.39.040(c), and § 27.30.030(c)). This is a recurring limiting principle across multiple commercial chapters.
Directional signs for parking areas are permitted “in accordance with Title 25” (so technical dimensions/placement are in Title 25). For projects, cross‑check parking sign allowances with San Mateo Parking.
Title 27 preserves narrow exceptions that allow certain signs in otherwise restricted districts (for example: sale/rental signs in agricultural or other districts). See the permitted‑uses lists where sale/rental signs are explicitly allowed.
Structural/electrical/construction performance for signs is governed by the California Building Standards (the state building code, especially Appendix H—Signs, and sign construction rules) when construction/building permits are required. See Appendix H in the California Building Code.

District-by-district breakdown (Title 27 references)

Note: each district subsection below summarizes what Title 27 itself says about signs. For specific size/height/illumination/permit thresholds you must consult Title 25 (Title 27 explicitly points to Title 25 in several places). Verify with the Zoning Administrator for parcel‑specific interpretations.

C1 — Neighborhood Commercial (Chapter 27.30)

Purpose / where it applies: neighborhood commercial strips and small shopping areas; see Chapter 27.30.
Typical permitted uses: retail, services, offices; ground‑floor retail requirements exist in some areas.
Sign rules in Title 27: exterior signs displayed shall pertain only to a use conducted within the building (this is the controlling phrase in § 27.30.030(c)). Technical sign dimensions and classifications are not included in this chapter (Title 25 controls).
Practical: Multi‑tenant buildings must plan signage consistent with the “on‑site use” rule; check Title 25 for tenant panel sizing and storefront signage allowances.

C2 — Regional / Community Commercial (Chapter 27.32)

Purpose / where it applies: larger community shopping centers and regional retail nodes; see Chapter 27.32.
Typical permitted uses: broad retail, hotel, office, and service uses.
Sign rules in Title 27: exterior signs must pertain only to uses conducted within the building (§ 27.32.030(c)). Parking area directional signs are permitted per Title 25 references elsewhere.
Practical: For signs that face a public right‑of‑way (directional, tenant blade signs, pole signs), expect Title 25 and SPAR/design review scrutiny.

CBD — Central Business District (Chapter 27.38)

Purpose / where it applies: downtown commercial core; see Chapter 27.38.
Typical permitted uses: retail, offices, mixed‑use; the Downtown plan prescribes required retail frontage.
Sign rules in Title 27: Chapter notes that name plates and signs are “as classified and regulated in Title 25” and downtown retail frontage policies emphasize storefront visibility (§ 27.38.020(c)).
Practical: Downtown signage is specifically routed to Title 25 and also to downtown design guidelines — expect combined review under SPAR and downtown overlay rules.

CBD Support (Chapter 27.39)

Purpose / where it applies: transitional commercial uses that support the CBD.
Sign rules in Title 27: Any exterior sign displayed shall pertain only to a use conducted within the building (§ 27.39.040(c)).

Open Air Vendors (Use rules — Chapter 27.67)

Where it applies: permitted on executive or commercial (including CBD) private property subject to special permit rules.
Sign standard in Title 27: signs are limited to non‑electrical signs permanently affixed to the vendor’s conveyance and total sign area shall not exceed 6 square feet (§ 27.67.060(f)).

Recycling Facilities / Reverse Vending Machines (Chapter 27.69)

Where it applies: recycling centers and reverse vending machines.
Sign standards in Title 27: reverse vending machine signage limited to 4 sq ft per machine (not including operating instructions); recycling facility signage limited to 16 sq ft (not including operating instructions) (§ 27.69.030(a)–(b)).

Qualified Overlay Districts (example: Q8)

Where it applies: limited overlay areas with site‑specific conditions. For example Q8 explicitly allows “Signage on the site … in accordance with Title 25” (§ (Q8) conditions).
Practical: many overlays punt technical sign rules to Title 25 but may add design or thematic expectations in the overlay language — check the particular overlay chapter.

Quick decision table (most decision‑relevant standards / permitted uses)

What (use / standard)	What Title 27 requires	Code Reference
Recycling machines — maximum sign area	Reverse vending machines signage ≤ 4 sq ft per machine; recycling facility signage ≤ 16 sq ft (operating instructions excluded).	§ 27.69.030(a)–(b)
Open‑air vendor signs	Vendor signage non‑electrical, permanently affixed, total ≤ 6 sq ft.	§ 27.67.060(f)
Exterior signs in many commercial districts	Exterior signs must pertain only to a use conducted within the building (limiting off‑site advertising).	§ 27.32.030(c), § 27.39.040(c), § 27.30.030(c)
Freestanding signs / planned signing districts	Planning Application required for planned signing districts and freestanding signs over 8 feet in commercial districts (PA trigger).	§ 27.08.010(a)(13)
Downtown/CBD nameplates & signs	Regulated by Title 25 (Title 27 defers classification & regs to Title 25).	§ 27.38.020(c)
Structural/electrical sign construction	Sign construction & electrical illumination governed by state code (Appendix H and other CBC provisions).	California Building Code Appendix H (see Appendix H—Signs)

Checklist — what an applicant must satisfy (pre‑application checklist)

Confirm whether the proposed sign is covered by Title 27 (small‑use caps like recycling or vendor) or by Title 25 (most commercial/residential signs). Verify with the Zoning Administrator. Verify Title 25.
If freestanding sign > 8 ft or a planned signing district is proposed, prepare a Planning Application (PA) per § 27.08.010(a)(13).
For projects requiring Site Plan & Architectural Review, include sign elevations and materials in the SPAR package per § 27.04.130 and SPAR rules. Link to design review materials.
For downtown/CBD properties or overlays, confirm overlay conditions and Title 25 requirements (CBD has retail frontage rules and directs signs to Title 25).
For structural or illuminated signs, coordinate building and electrical permits (California Building Standards Code / Appendix H).
For directional/parking signage, cross‑check parking standards and directional sign allowance with San Mateo Parking.

Risks & Ambiguities

Issue	Why it matters	What to verify
Title 27 frequently defers details to Title 25	Title 27 gives policy and a few small exceptions but not the full technical standards; relying only on Title 27 risks missing permit triggers, area/height caps, and illumination rules.	Verify the full sign classification, permit thresholds, and dimensional standards in Title 25. Not found in retrieved materials.
“Signs must pertain only to a use conducted within the building”	That language limits off‑site advertising and some multi‑tenant sign strategies; ambiguous for multi‑tenant centers or shared pylon signs.	Verify how Title 25 and the Zoning Administrator treat multi‑tenant pylon signs, tenant panels, and directory signage. Verify with the Zoning Administrator.
Freestanding signs > 8 ft trigger a planning application	Being surprised by a PA requirement doubles time/cost and adds public notice.	If a freestanding or tall sign is planned, confirm whether the sign exceeds 8 ft and what application materials the City requires (PA + SPAR + public notice). § 27.08.010(a)(13).
Overlay or Specific Plan references to Title 25	Overlays may add design expectations even though Title 25 sets technical specs.	Review overlay chapter text (e.g., Q8, Bay Meadows, Hillsdale) for supplemental signage direction and verify design standards.
Structural/electrical code obligations	Even if zoning permits a sign, it must meet structural (wind/seismic) and electrical safety rules under the building code.	Coordinate building permits and apply CBC Appendix H (sign construction), and electrical code.

Plain‑English Summary

Title 27 sets policy about where and when signs are allowed (and gives a few small, use‑specific size caps), but it does not hold the full technical sign schedule — most of the size, height, and illumination rules are in Title 25 and sign construction rules live in the state building code; for any commercial sign, check Title 25 and expect planning review if the sign is freestanding and taller than 8 feet.

Information Gaps

The uploaded Title 27 excerpts repeatedly point to Title 25 for the comprehensive sign regulations, but the actual Title 25 sign code (detailed area, height, illumination, permit fees, processing timelines, and design standards) was Not found in retrieved materials. Verify Title 25 directly.
Specific rules for multi‑tenant pylon signs, sign height tables, cumulative sign area calculation, and illumination/LED/message center standards are Not found in the Title 27 excerpts and must be read in Title 25 or clarified with staff. Not found in retrieved materials.
Application filing forms, fees, and processing steps for planned signing districts are not present in Title 27 beyond the PA trigger; check the Planning Division and Title 25 for submittal checklists. Not found in retrieved materials.

Source References

§ 27.69.030 (Recycling facility signage limits) — Title 27.
§ 27.67.060(f) (Open air vendor sign cap: 6 sq ft, non‑electrical) — Title 27.
§ 27.08.010(a)(13) (PA required for planned signing districts & freestanding signs over 8 ft) — Title 27.
§ 27.32.030(c) (Exterior signs must pertain only to on‑site use) — Title 27.
§ 27.39.040(c) (Exterior sign rule for CBD Support) — Title 27.
§ 27.30.030(c) (Exterior sign rule for C1 / neighborhood commercial) — Title 27.
§ 27.38.020(c) (CBD nameplates and signs are “as classified and regulated in Title 25”) — Title 27.
Q8 overlay example: signage allowed “in accordance with Title 25” — Title 27 overlay language.
Directional signs for parking: permitted in accordance with Title 25 — Title 27 (see parking chapter cross references).
California Building Code — Appendix H (Signs) — state structural/electrical/construction standards for signs.

Sources

Retrieved passages

San Mateo Zoning Code (Section 27.08.030) Medium relevance
San Mateo Zoning Code (chapter shall) Medium relevance
CBC § 120 Medium relevance
CBC § 3 (Chapter 27.66.) Medium relevance
San Mateo Zoning Code (Title and) Medium relevance
San Mateo Zoning Code (Chapter 27.12) Medium relevance
San Mateo Zoning Code (Article II) Medium relevance
San Mateo Zoning Code (Chapter 27.40) Medium relevance
San Mateo Zoning Code (Chapter 27.74) Medium relevance
San Mateo Zoning Code (Section 27.60.160) Medium relevance
San Mateo Zoning Code (Section 27.64.023) Medium relevance
San Mateo Zoning Code (Chapter 27.60) Medium relevance
CEC § H103 (SECTION H103) Medium relevance
CBC § H101 (SECTION H101) Medium relevance
CBC § H103 (SECTION H103) Medium relevance
CEC § H101 (chapter as) Medium relevance
San Mateo Zoning Code (Section 27.38.110) Medium relevance
San Mateo Zoning Code (Section 2.24.010) Medium relevance

Cited sections

Official San Mateo code library

Frequently asked questions

Where are the sign size, height and illumination rules for San Mateo?

Title 27 does not contain the full schedule of sign dimensions — it contains a few narrow caps and many cross‑references that delegate classification and technical sign standards to Title 25; Title 27 chapters repeatedly direct you to Title 25 (for example § 27.38.020(c)). Check Title 25 for the full size, height, and illumination rules; Title 27 supplies use‑level guidance and PA triggers.

Do I need a planning application for a freestanding sign in San Mateo?

If the sign is part of a planned signing district or a freestanding sign over 8 feet in a commercial district you must file a Planning Application (PA) under § 27.08.010(a)(13). Always confirm with the Planning Division because overlays or specific plans can add additional requirements.

Can an open‑air vendor in San Mateo use illuminated signage?

No — Title 27 specifically limits open air vendor signs to non‑electrical signs permanently affixed to the vendor’s conveyance with total area not to exceed 6 square feet (§ 27.67.060(f)). Illuminated signs are therefore not allowed for these vendors under that rule.

Where are the small exceptions (like recycling machines) handled?

Title 27 contains those narrow, use‑specific caps. For example reverse vending machines are limited to 4 sq ft signage per machine and recycling facilities to 16 sq ft (§ 27.69.030). For larger or different facility types, refer to Title 25 for general sign types and caps.

Does Title 27 allow off‑site advertising?

Title 27’s repeated language in commercial districts states that exterior signs shall pertain only to a use conducted within the building (see § 27.32.030(c), § 27.39.040(c), § 27.30.030(c)). This limits off‑site advertising; any directory or multi‑tenant solution must be evaluated against Title 25 and the Zoning Administrator’s interpretation.

Who enforces sign compliance and who approves variances?

The Zoning Administrator enforces Title 27 and has specific approval powers (including review of freestanding signs within certain limits). For any deviation you may need a variance or special permit per Title 27 procedures; check Chapters 27.06–27.08 for approval bodies and appeals. Verify exact procedures with the Planning Division.

Are directional/parking signs governed differently?

Directional signs in parking areas are permitted “in accordance with Title 25” (see parking cross references in Title 27). Always coordinate directional signage with [San Mateo Parking] standards and Title 25 where the technical specs reside.

Do I need a building permit for an illuminated or large sign?

Yes — structural, wind, seismic and electrical criteria for signs are governed by the California Building Standards (see Appendix H—Signs and related CBC provisions). Even if zoning permits a sign, you must obtain the required building/electrical permits and comply with Appendix H.

What about signs in overlays and specific plans (e.g., Bay Meadows, Hillsdale)?

Many overlays reference Title 25 for sign technicals but may add design expectations or require compliance with special streetscape and signage policies; overlay chapters frequently state Title 27 standards govern except where the overlay provides otherwise. Read the applicable overlay chapter and verify whether it modifies Title 25 requirements.

If I have a multi‑tenant shopping center, how are tenant signs handled?

Title 27 requires signs to “pertain only to a use conducted within the building,” but it defers classification and detailed rules (tenant panel sizes, pylon/monument allowances) to Title 25. For a multi‑tenant center, review Title 25 and coordinate a signage program with the Zoning Administrator and design review/SPAR as needed.

Ask about any San Mateo property

Get a cited, plain-English answer on San Mateo zoning, setbacks, FAR, ADUs and permits — for any address.

Start Free Trial