Why are Mills Estate homes in Burlingame and not Millbrae?

Because of a 1946 annexation and the litigation that followed. Burlingame annexed a 100-foot-wide strip of the Mills Estate along its northern boundary, shaped roughly like a horseshoe or the letter U, encircling about 730 acres that were not annexed. A day later a petition was filed to incorporate Millbrae and capture both. Burlingame's annexation was voided, then reversed on appeal in March 1949 in Burlingame's favour; a related appellate decision in 1951 went against the intervener. The land stayed Burlingame, and the Eichlers built there fourteen years later carry Burlingame addresses.

1946 – 1951 · City of Burlingame v. County of San Mateo

A hundred-foot strip in the shape of a U.

Seventeen years before the first Eichler went up here, two cities fought over this hilltop and the fight went to the Court of Appeal. The manoeuvre at the centre of it is one of the more audacious pieces of municipal geometry in San Mateo County history, and it is the reason these houses are Burlingame addresses with Burlingame schools.

103 Cal.App.2d 885

Unlike most of what is written about this tract, this part is not marketing copy or local legend. It is a published appellate decision, and the description of the annexation's shape is the court's own.

A grey Eichler in Burlingame, with a level flat roof and clerestory band across the front and a glazed gable rising behind it, an olive tree, a two-car garage and a brick-edged path. — **The gable, set back.** Here the gable sits **behind** the flat roof line rather than over the entry, so it reads as a lit room beyond rather than as a porch. Same components, different arrangement — which is the clearest sign this tract was not built from a single plan.

What happened

Annex the ring, not the middle.

In 1946 the City of Burlingame annexed a strip of the Mills Estate along its northern boundary. The strip was a hundred feet wide and, in the court's own words, ran “in the shape, roughly, of a horseshoe or the letter ‘U’” — encircling roughly 730 acres that were not annexed at all.

The effect was to draw a city boundary around the prize without taking it. Any later attempt to incorporate or annex that interior land would have to reckon with the fact that Burlingame now surrounded it on three sides.

One day later, a petition was filed to incorporate the City of Millbrae — and the proposed incorporation took in both the strip and the 730 acres inside it.

How it ended

Voided, then reversed.

Burlingame's annexation was challenged and voided in a quo warranto proceeding — the old writ by which the state asks an official or a body by what authority it claims a power.

That did not hold. In March 1949 the Court of Appeal reversed, in Burlingame's favour. A related appellate decision in 1951 went against the intervener, reported at City of Burlingame v. County of San Mateo, 103 Cal.App.2d 885.

The hilltop stayed Burlingame. Five years later the mansion burned and Trousdale cut the land into lots; nine years after that, Eichler started selling houses on it.

Why an owner should care

This is not trivia. It sets four things you deal with every year.

Your schools. Burlingame Elementary School District and San Mateo Union High School District — Franklin, Burlingame Intermediate, Burlingame High. Had the 1946 manoeuvre failed, this ridge would plausibly be Millbrae, and these addresses would feed Mills High School instead. The schools →

Your permits. You apply to the City of Burlingame, and Burlingame runs residential design review. That is a materially different experience from the San Mateo Highlands, where the tract is unincorporated county and there is no design review, no overlay and no guidelines at all. The comparison →

Your address. ZIP 94010, and the Burlingame side of a neighbourhood name that also exists in Millbrae under 94030. Portals conflate the two. On the ZIP →

Your comparables. A Millbrae “Mills Estates” sale is not a comparable for a Burlingame Mills Estate Eichler. Different city, different schools, different housing stock, and in most cases not an Eichler at all. This is the most common error we see in valuations of these houses. How we handle it →