Hillsborough — Signage

Last reviewed: July 2, 2026

Overview

Hillsborough controls signs in a short, use-focused chapter: Chapter 17.48 (Signs) of the Hillsborough Zoning Ordinance (Title 17). The code establishes a townwide prohibition on posting signs except where explicitly allowed (temporary, real‑estate/contractor, political, private‑school banners, etc.), and it cross‑references other local permit rules (garage/estate sales, fundraising events) and state/federal law. Key numeric limits you will actually use in practice are the 12" × 15" limit for real‑estate/contractor signs and the 4' × 8' private‑school fundraiser banner limit. See § 17.48.010–.070 for the controlling rules.

Note: this page sticks to what the Hillsborough zoning/planning ordinance says about signage. For structural, electrical, or accessibility rules (Title 24 / building code) see the California Building Standards Code. California Building Standards Code

Townwide rules and quick legal anchors

• "Sign" is defined in § 17.48.010 (broad, includes banners, posters, advertising devices; street‑address letters and certain flags are carved out).
• Posting any sign is generally unlawful unless it fits an allowed category in § 17.48.020–.030.
• Specific allowances/limits:
  • Real‑estate and contractor signs: one sign per property, max 12 in × 15 in, black on white with specified content; time limits tied to permit/sale completion (§ 17.48.040).
  • Private school signs: generally prohibited from street visibility, with one limited fundraiser banner per year (max 4 ft × 8 ft, posted no sooner than 3 weeks before the event and removed within one week) (§ 17.48.070).
  • Fundraising event signs: governed by the town's event rules at § 5.16.040 (cross‑referenced from § 17.48.050).
  • Political signs: regulated only to the extent allowed by state/federal law; the chapter defers to higher authority (§ 17.48.060).
• Garage/estate‑sale sign rules and time windows are in § 17.44.020–.030 (cross‑referenced in the signs chapter).

Practical note: Chapter 17.48 is a townwide sign chapter; zoning districts do not have a separate sign schedule in the code, but other use‑specific rules in the zoning chapters (for example home‑business standards) place sign limits on specific uses. See the district summaries below. Hillsborough Zoning

District‑by‑district breakdown (how signage plays out in each district)

Hillsborough's current zoning districts relevant to residential and town‑owned land are established in Chapter 17.12 as RD‑1, RD‑2, and RD‑3. The sign rules in Chapter 17.48 apply townwide, but district use rules modify where signs may arise (private schools, town facilities, home businesses, etc.).

RD‑1 (Traditional Residential)

• Purpose: RD‑1 preserves single‑family character; density limit is one dwelling per one‑half acre (exclusive of ADUs). § 17.16.010.
• Typical permitted uses: single‑family dwellings, accessory structures, country club (where applicable), accessory dwelling units (ADUs) — see the uses table in § 17.16.010(B).
• Signage implications:
  • The townwide prohibition/allowances of § 17.48 control signs in RD‑1; temporary sale signs, permitted contractor signs, and address signage are the usual exceptions.
  • Home businesses in RD‑1 require a permit and, crucially, the code states “there are no signs or structures anywhere on the premises … which advertise, identify, or otherwise relate to the home business” as an approval standard (§ 17.16.015(B)(4)). That effectively prohibits business signage for permitted home businesses.
• Key dimensional/development standards (affecting sign siting): front/side/rear setback rules and the 25‑ft street‑line setback are in § 17.24 and the building envelope/height limits in § 17.28; these determine whether any freestanding sign could be located in the setback area — but freestanding commercial signage is rare in RD‑1.

RD‑2 (Mixed Residential)

• Purpose: RD‑2 accommodates townhome/multifamily on certain town‑owned land; minimum density 20 units/acre where applied. § 17.16.010.
• Typical permitted uses: multifamily housing, town facilities, public parks, certain public buildings; private schools are a special permit use.
• Signage implications:
  • The basic allowances/restrictions in Chapter 17.48 apply. For multifamily or town facilities, signage beyond contractor/real‑estate/temporary types would be governed by permit or design review or the specific use permit; the sign chapter itself contains no separate RD‑2 size schedule.
  • Emergency shelters allowed in RD‑2 are subject to no exterior signage except as outlined in Chapter 17.48 (see emergency‑shelter standards referencing signage). § 17.16.010(B)(1)(e) and related text.

RD‑3 (Governmental & Residential Mixed Use)

• Purpose: RD‑3 is for town facilities and limited residential on town‑owned land; caps at sixteen dwelling units on mapped land. § 17.16.010.
• Typical permitted uses: town facilities, public buildings, some multifamily uses (by table).
• Signage implications:
  • Town facilities and public buildings will be subject to Chapter 17.48 plus any signage conditions imposed with the facility permit or design review. There is no different sign area table in the zoning text; refer to § 17.48 for what the town allows, and verify any larger identity signage via the town's permitting/design review process.

Practical pointer: because the code places the core numeric sign limits in the standalone signs chapter and places use‑specific constraints (like the home‑business no‑signs rule) in the use chapters, you must check both Chapter 17.48 and the underlying use section for the parcel's zoning district when evaluating signage. Hillsborough Development Standards

Table — Most decision‑relevant sign standards (quick reference)

Checklist — what an applicant should verify before installing a sign in Hillsborough

• Confirm the proposed sign is a type expressly allowed under § 17.48.030 (temporary safety, garage/estate sale, real‑estate/contractor, temporary address, fundraising, etc.).
• For real‑estate or contractor signs, confirm size/content limits (one sign per property; 12" × 15"; black on white) and timing rules per § 17.48.040.
• If the sign is for a private school fundraising banner, confirm event permit under § 5.16.040 and the 4' × 8' banner/time limits in § 17.48.070.
• If the sign is connected to a home business, confirm a valid home‑business permit and that the sign would not violate § 17.16.015(B)(4) (no onsite business signage).
• Check setback/street‑line restrictions and permitted sign location in relation to § 17.24 setbacks and Chapter 12.12 outdoor fixtures (these affect whether a freestanding sign is allowed where you plan to place it). Hillsborough Parking Hillsborough Development Standards
• Verify whether design review or a use permit applies to the underlying use (town facility, private school, or other special uses) — design review can affect appearance/placement. Hillsborough Design Review
• For illuminated or large structural signs, check building code and electrical requirements (Title 24 / state building standards). California Building Standards Code
• Where the code text is silent or an interpretation is needed, contact the planning office and verify with the jurisdiction (verify whether a sign permit is required and whether design review conditions apply). Hillsborough Zoning

Risks & Ambiguities

Plain‑English summary

Hillsborough bans signs by default and only allows a short list of exceptions: contractor/real‑estate signs (tiny, 12" × 15"), certain temporary safety/event/sale signs, private‑school fundraiser banners (one per year, 4' × 8'), and political signs to the extent state/federal law allows. Home businesses may not put signs on the property. Always confirm the specific use chapter and event/permit cross‑references before you install anything. § 17.48 and § 17.16.015 are the two most important local rules.

Source References

• Hillsborough Zoning Ordinance (Title 17) — Chapter 17.48, Signs: § 17.48.010–§ 17.48.070.
• Hillsborough Zoning Ordinance — Uses permitted and district descriptions, including RD‑1, RD‑2, RD‑3 and the uses table: § 17.12 and § 17.16.010.
• Hillsborough Zoning Ordinance — Home business standards (no onsite business signage): § 17.16.015(B)(4).
• Garage/estate sale sign rules referenced by the signs chapter: § 17.44.020–.030.
• Fundraising events cross‑reference: § 17.48.050 references § 5.16.040(F) (fundraising event permits).
• Hillsborough development and setback context (setbacks/building envelope that affect sign siting): § 17.24 and § 17.28.
• For technical construction/illumination/permitting standards consult the California Building Standards Code (Title 24) — note: the local ordinance defers structural/permit specifics to building/electrical codes. California Building Standards Code

Information Gaps (what the ordinance text did not state explicitly in retrieved materials)

• Local fee/permit procedure for installing a permanent or illuminated sign (the signs chapter lists allowed signs and sizes but does not show an explicit "sign permit" application or fee schedule). Not found in retrieved materials — Verify with the town.
• Illumination / lighting power limits for signs (no local wattage or lumen limits for sign illumination found; building/electrical rules may apply). Not found in retrieved materials — consult building department / Title 24.
• Any district‑level sign area table (commercial zones typical in other cities): Hillsborough's zoning sections do not contain a separate sign schedule per district; Chapter 17.48 is the controlling sign chapter. Not found in retrieved materials — Verify with the town for any site‑specific approvals.

Retrieved passages

• Hillsborough Zoning Code (Section 12.12.050) High relevance show source text
• Hillsborough Zoning Code (§ 23) Medium relevance show source text
• Hillsborough Zoning Code (§ 24) Medium relevance show source text
• CEC § H101 (chapter as) Medium relevance show source text
• Hillsborough Zoning Code (Section 65915) Medium relevance show source text
• CBC § 1138A.4 (Section 1138A.4) Medium relevance show source text
• CBC § 0479 Medium relevance show source text
• Hillsborough Zoning Code (Chapter 17.48) Medium relevance show source text
• California Building Code Medium relevance show source text
• Hillsborough Zoning Code (§ 3) Medium relevance show source text
• CBC § 606 Medium relevance show source text
• Hillsborough Zoning Code (Chapter 2.12) Medium relevance show source text
• Hillsborough Zoning Code (Title 17) Medium relevance show source text
• CRC § 304.8 Medium relevance show source text
• Hillsborough Zoning Code (Section 17.16.020) Medium relevance show source text
• CRC § 2025 (CHAPTER 1) Medium relevance show source text
• CRC § 304.8 Medium relevance show source text
• CBC § H101 (SECTION H101) Medium relevance show source text
• Hillsborough Zoning Code (Section 17.16.015) Medium relevance show source text
• Hillsborough Zoning Code (section shall) Medium relevance show source text

Cited sections

• Hillsborough Zoning Ordinance (Title 17) — Chapter 17.48, Signs: **§ 17.48.010–§ 17.48.070**. (Title 17)
• Hillsborough Zoning Ordinance — Uses permitted and district descriptions, including **RD‑1**, **RD‑2**, **RD‑3** and the uses table: **§ 17.12** and **§ 17.16.010**. (§ 17.12)
• Hillsborough Zoning Ordinance — Home business standards (no onsite business signage): **§ 17.16.015(B)(4)**. (§ 17.16.015)
• Garage/estate sale sign rules referenced by the signs chapter: **§ 17.44.020–.030**. (§ 17.44.020)
• Fundraising events cross‑reference: **§ 17.48.050** references **§ 5.16.040(F)** (fundraising event permits). (§ 17.48.050)
• Hillsborough development and setback context (setbacks/building envelope that affect sign siting): **§ 17.24** and **§ 17.28**. (§ 17.24)
• For technical construction/illumination/permitting standards consult the California Building Standards Code (Title 24) — note: the local ordinance defers structural/permit specifics to building/electrical codes. California Building Standards Code (Title 24)
• Hillsborough_ZoningCode.md
• 2025 California Building Code.md

• Official Hillsborough code library