645 William Cunningham Avenue

This 4-bedroom, 4-bath main residence pairs period character with modern comfort. Craftsman details, timeless proportions, and a warm, livable floor plan carry throughout the approximately 4,818 sq ft main residence. The grounds are just as special. Mature landscaping surrounds the in-ground pool, creating a private setting for afternoons outdoors, entertaining, and relaxed Sonoma living. The 3-car garage includes a convenient shower room, ideal for pool days, gardening, or a quick post-workout rinse. Above the garage, an approximately 825 sq ft carriage house offers a simple, private escape for guests, a home office, or studio. Just five blocks from Sonoma Plaza, the property is close to boutiques, tasting rooms, Michelin-starred and acclaimed restaurants, and the heart of downtown Sonoma. With approximately 4,018 sq ft in the main house plus an additional 825 sq ft carriage house and a total of 6 full bathrooms, this is a rare opportunity to own a remarkable piece of Sonoma's architectural heritage.

Days on Market

7 days

Current Status

Active

Original Price

List Price

$5,650,000

On Market Date

Sep 29, 2026

Property Type

Single Family Residence

Area

Sonoma

Zip Code

95476

MLS ID

326082579

APN

127700026000

Year Built

1998

Stories in Building

2

Possession

Close Of Escrow

Data Source

BAREIS

Origin MLS System

Bed

5

Bath

6

Parking

3

24'+ Deep Garage, Detached

SQ FT

4,818

SQ FT Source

Not Verified

Lot SQ FT

20,007.0

Lot Acres

0.4593 Acres

Pool Info

Built-In, Solar Heat

Cooling

Central Air

Disclosures

Standard

Fire Place

Gas Log, Gas Starter, Stone

Heating

Central, Fireplace(s)

Laundry

Inside Room

Main Level

Dining Room, Family Room, Kitchen, Living Room

Possession

Close Of Escrow

Basement

None

Fee

$0

MLS and other Information regarding properties for sale as shown in Theo have been obtained from various sources such as sellers, public records, agents and other third parties. This information may relate to the condition of the property, permitted or unpermitted uses, zoning, square footage, lot size/acreage or other matters affecting value or desirability. Unless otherwise indicated in writing, neither brokers, agents nor Theo have verified, or will verify, such information. If any such information is important to buyer in determining whether to buy, the price to pay or intended use of the property, buyer is urged to conduct their own investigation with qualified professionals, satisfy themselves with respect to that information, and to rely solely on the results of that investigation.

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