643 Jay Street

Off Market

643 Jay Street

Los Altos CA 94022

1408 sq. ft.

19900 sq. ft.

Single-Family

Last sold for $5,900,000

Owen Halliday, last sold this property on 17 February 2026 after 34 days on market.

Overview

First time on the market in more than 50 years. An exceptional land-value opportunity in one of Los Altos most coveted neighborhoods. Set on an impressive 19,900 (appr.) SF parcel, this tranquil property offers a rare canvas for builders, investors, or visionary buyers seeking to create a custom estate in a truly special location. The existing residence consists of a 3-bedroom, 1.5-bath main home, complemented by an independent in-law unit with 2 bedrooms, a full bath, a generous living area, and a kitchenette - for a total of 5 bedrooms, 2 full and 1 half baths. While the structures are ready for transformation, the true value lies in the expansive lot, tranquil setting, and exceptional location. The oversized grounds present abundant possibilities for new construction, thoughtful expansion, or a complete reimagining of the property, subject to buyer verification. Mature surroundings and a spacious footprint provide the ideal foundation for a future luxury residence with ample outdoor living. Just minutes from top-rated Los Altos schools (Almond Elementary, Egan Middle, and Los Altos High), downtown shops and dining, parks, and major Silicon Valley commute routes, this is a rare opportunity to secure a large parcel in a premier location and bring a bold vision to life.

Features

5 bedrooms

3 bathrooms

2 carspaces

2 garage spaces

1408 sq. ft. floor area

19900 sq. ft. lot size

Single-Family

Estimated Value

Based on this property and similar 5 bedroom single-family properties sold in Los Altos over the last 12 months, the estimated median property value of 643 Jay Street is $6.2m.

Median value

$6.2m

Estimated value range

$3.22m - $14.8m

Median days on market

Estimated value trend

-6%

decrease over the last 12 months

Average days on market is based on recent, comparable sales in Los Altos. It is only an indication of the time a property is actively listed and should not be relied upon as an accurate representation of how soon a property will be sold.

Property history for 643 Jay Street

2026

Sold

$5,900,000

17 Feb 2026 by Owen Halliday, of Sereno

Happy sellers in Los Altos

94%

94% of sellers in Los Altos reported that their sale price either exceeded or met their price expectations.

Los Altos stands out for consistently delivering exceptional satisfaction and strong market results for homeowners.

This is based on voluntary sentiment collected from 3 reviews in Los Altos over the last 12 months.

Local market activity for 5 bedroom single-family properties in Los Altos

In the last 12 months, 51 five-bedroom single-family properties similar to 643 Jay Street, have been sold.

This represents a 10% increase in five-bedroom single-family properties sales when compared to the previous 12 months.

Sold

For Sale

Interested in selling?

People are reaching out to these agents in Los Altos for a market analysis.

Mary Sanbrook

at Signature Properties

(24 reviews)

Get a market analysis

Julie Lovelace

at Fireside Realty

(4 reviews)

Get a market analysis

Mini Kalkat

at Intero Real Estate Services

(3 reviews)

Get a market analysis

Sue Cheng

at Intero Real Estate Services

Get a market analysis

Nearby agents

Compare and contact these top performing agents who’ve delivered exception customer service for their clients in Los Altos

Mary Sanbrook

Sellers who recommend Mary Sanbrook have praised them for being responsive, local expert, empathetic, clear communication, detail-oriented, pleasant, and supportive