21 Decatur St #3 is a 1,136 square foot condo with 3 bedrooms and 2.5 bathrooms. Based on Redfin's Cambridge data, we estimate the home's value is $1,518,369.
CondoProperty Type
1873Year Built
$1,337Est. Price/Sq.Ft.
Source:Public Records
Redfin Estimate
$1,518,369
$9,000 since July
Recently sold homes
Estimate history
Homes for sale
This home's estimate is 37.5% higher than the average sale price ($1.10M) of 6 comparable homes.
As the MLS and public records start to fill up, we'll list the details here.
Year
Property tax
Land + Additions
Assessment*
2025
$9,225 (+7.8%)
$1,452,800
2024
$8,560 (+5.6%)
$1,445,900
2023
$8,108 (+10.4%)
$1,383,700
2022
$7,343 (+0.9%)
$1,240,300
2021
$7,274 (+6.2%)
$1,243,400
2020
$6,850 (+4.2%)
$1,191,300
2019
$6,573 (+2.7%)
$1,106,600
2018
$6,398 (+3.0%)
$1,017,200
2017
$6,213 (+4.4%)
$957,300
2016
$5,954 (+0.9%)
$851,800
2015
$5,903 (+1.3%)
$754,900
2014
$5,827 (+4.4%)
$695,300
2013
$5,584
$644,800
Tax history for 21 Decatur St #3
Year
Property tax
Land + Additions
Assessment*
2025
$9,225 (+7.8%)
$1,452,800
2024
$8,560 (+5.6%)
$1,445,900
2023
$8,108 (+10.4%)
$1,383,700
2022
$7,343 (+0.9%)
$1,240,300
2021
$7,274 (+6.2%)
$1,243,400
2020
$6,850 (+4.2%)
$1,191,300
2019
$6,573 (+2.7%)
$1,106,600
2018
$6,398 (+3.0%)
$1,017,200
2017
$6,213 (+4.4%)
$957,300
2016
$5,954 (+0.9%)
$851,800
2015
$5,903 (+1.3%)
$754,900
2014
$5,827 (+4.4%)
$695,300
2013
$5,584
$644,800
*Taxable value of land and structures on it ("additions") is determined regularly by local assessors and does not affect market price.
Property details
Interior
Basement Information
Basement Sq. Ft: 546
Bathroom Information
# of Full Baths: 2
# of 1/2 Baths: 1
Heating & Cooling
Heating Type: Forced Air
Room Information
# of Rooms: 6
Exterior
Exterior Information
Physical Condition: Very Good
Property Information
Living Sq. Ft: 1,136
Gross Sq. Ft: 1,682
Ground Floor Sq. Ft: 1,136
# of Stories: 3
Lot Information
# of Buildings: 1
Municipality Name: CAMBRIDGE
State Use Description: CONDOMINIUM
Financial
Assessor Information
Assessment Year: 2025
Public facts
Beds: 3
Baths: 2.5
Sq. Ft.: 1,136
Stories: 3.0
Lot Size: —
Style: Condo/Co-op
Year Built: 1873
Year Renovated: —
County: Middlesex County
APN: 4867546
Home facts updated by county records on Jul 16, 2026
Around this home
Schools
The Amigos School
Public PreK-8 • Assigned • 0.2mi
9/10
Provided by GreatSchools
Lifestyle
Provided by Walk Score and Local Logic
Local insights from Redfin agents
Despite new zoning laws encouraging housing production, Cambridge remains a Seller's market driven by pent-up demand and a constant influx of buyers. Because it is a historic, built-out city, there is little new housing to replace existing...
properties, & true supply growth is severely constrained.