Is the San Mateo Highlands in the City of San Mateo?

No. The entire Highlands Eichler tract is unincorporated San Mateo County. County LAFCo lists Highlands among the unincorporated communities within the City of San Mateo's sphere of influence, and a sphere of influence is not annexation. Mail addresses read San Mateo, CA 94402, which is the source of most of the confusion.

Who issues building permits in the San Mateo Highlands?

San Mateo County Planning & Building, not the City of San Mateo. County zoning and County code apply, and law enforcement is the San Mateo County Sheriff, who maintains a substation at the Highlands recreation centre.

Will I be notified if my neighbour applies for a second story?

Not necessarily. An Eichler Network forum thread records the County permit office telling a Highlands resident that a permit had been issued and that neighbour notification was not required. Check current County noticing requirements for the specific application type rather than assuming.

The most consequential fact on this site

Your mail says San Mateo. Your government doesn't.

The entire Highlands Eichler tract is unincorporated San Mateo County. Not the City of San Mateo — the County. It is inside the city's sphere of influence, which sounds like something and confers nothing. If you are buying here, this changes who reviews plans, who issues permits, who polices the street, and what recourse you have when something happens next door.

Jurisdiction: Unincorporated San Mateo County
Planning & building: San Mateo County Planning & Building
Law enforcement: San Mateo County Sheriff — substation at the recreation centre
City design review: None. It isn't the city's jurisdiction.
Recreation: County Service Area 1, a special district
Status with the city: Sphere of influence only. Not annexed.
19th Avenue Park: Different answer entirely — that tract is in the city

The single most consequential fact about buying in the Highlands, and the one almost every listing gets wrong. The mail says San Mateo. The permit counter is in Redwood City, at the County.

A wide daylight aerial of the San Mateo Highlands Eichler tract running up to Crystal Springs Reservoir, with Highway 92 and the watershed hills beyond. — None of this is the City of San Mateo. Every roof in this frame sits in unincorporated San Mateo County, and every permit pulled on them goes through the County. Boyenga Team photography

How we know

Four sources, all saying the same thing.

San Mateo County LAFCo — the body that actually decides municipal boundaries — lists Highlands among "the unincorporated communities of Highlands, Baywood Park, Baywood Plaza, the San Mateo County Campus at Paul Scannell Way, and Peninsula Golf Club" within the City of San Mateo's sphere of influence. A sphere of influence is a planning designation for territory a city might one day annex. It is not annexation.

The Highlands Recreation District's own FAQ describes its territory as approximately 2,500 residents across 800 homes "in unincorporated San Mateo County," and identifies itself as County Service Area 1.

The census record describes Highlands / San Mateo Highlands as an unincorporated community and census designated place.

And in practice: an Eichler Network forum thread records a Highlands resident calling about a neighbour's second-storey addition and being told by the County permit office that they had issued a permit and were not required to notify neighbours.

What it changes, concretely

Permits and plan check go through San Mateo County Planning & Building, in Redwood City — not the San Mateo city counter
Zoning and code are County zoning and County code
Design review — there is no city architectural review of any kind here, and the County has designated nothing in this tract
Policing is the County Sheriff
Neighbour noticing follows County rules, and may be narrower than you expect
Property tax allocation includes a share to CSA 1 depending on your street address
Your voter and service map is County, not city — which affects everything from road maintenance to who you call about a streetlight

Is this good or bad?

Neither, but it is different, and differences priced in ignorance tend to get priced wrong. The honest summary: County jurisdiction here has historically meant less architectural constraint than a city like Palo Alto imposes, which is good if you want to add on and bad if you were counting on the tract staying intact around you. Roughly sixty second storeys and seventy-plus heavily altered houses are the visible result of that trade.

What we would not do is let a buyer discover it after they are in contract.

Verify for your specific parcel

Everything on this page describes the Highlands Eichler tract as a whole. The CDP boundary and the Eichler tract boundary are not the same shape, and nearby unincorporated pockets and city territory interleave along the edges.

For any specific address, confirm jurisdiction from the County Assessor / parcel record before you rely on it. We will pull it for you if you are working with us, and you should not take a website's word for it — including ours.

They had a permit and they were not required to inform neighbours.

The other tract, for contrast

19th Avenue Park is inside the City of San Mateo. Parcel records place it in the city's Nineteenth Avenue neighbourhood, and it is bounded by S. Delaware Street, Concar Drive and S. Grant Street — well within city limits. City planning, city permits, city police. That tract →

Talk to us

We'll pull the parcel record before you write an offer.

Jurisdiction, zoning, permit history and what has actually been approved nearby. It takes us an afternoon and it has changed how more than one client felt about a house.