21 Ralph St is a 1,104 square foot house on a 8,712 square foot lot with 3 bedrooms and 2 bathrooms. Based on Redfin's Watertown data, we estimate the home's value is $911,104.
Single-familyProperty Type
1986Year Built
8,712 sq ftLot Size
$825Est. Price/Sq.Ft.
Source:Public Records
Redfin Estimate
$911,104
$27K since July
Recently sold homes
Estimate history
Homes for sale
This home's estimate is 5.6% lower than the average sale price ($965K) 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*
2026
$9,764 (+7.8%)
$504,900 + $295,400
$800,300
2025
$9,057 (+4.0%)
$504,900 + $270,500
$775,400
2024
$8,711 (−10.2%)
$482,400 + $262,100
$744,500
2023
$9,703 (+9.5%)
$459,400 + $255,100
$714,500
2022
$8,859 (+10.7%)
$436,500 + $232,100
$668,600
2021
$8,003 (+3.3%)
$421,200 + $232,100
$653,300
2020
$7,744 (+4.0%)
$405,800 + $232,100
$637,900
2019
$7,443 (−0.3%)
$390,500 + $187,400
$577,900
2018
$7,466 (+7.3%)
$382,900 + $171,400
$554,300
2017
$6,955 (+4.7%)
$329,300 + $171,400
$500,700
2016
$6,640 (−6.1%)
$314,000 + $171,400
$485,400
2015
$7,070 (+5.6%)
$291,000 + $179,400
$470,400
2014
$6,693 (+1.9%)
$268,000 + $179,400
$447,400
2013
$6,568 (+6.0%)
$268,000 + $179,400
$447,400
2012
$6,195 (+11.2%)
$250,800 + $179,400
$430,200
2011
$5,571 (+7.7%)
$250,800 + $149,400
$400,200
2010
$5,174 (+7.0%)
$264,200 + $124,500
$388,700
2009
$4,835
$269,200 + $125,800
$395,000
Tax history for 21 Ralph St
Year
Property tax
Land + Additions
Assessment*
2026
$9,764 (+7.8%)
$504,900 + $295,400
$800,300
2025
$9,057 (+4.0%)
$504,900 + $270,500
$775,400
2024
$8,711 (−10.2%)
$482,400 + $262,100
$744,500
2023
$9,703 (+9.5%)
$459,400 + $255,100
$714,500
2022
$8,859 (+10.7%)
$436,500 + $232,100
$668,600
2021
$8,003 (+3.3%)
$421,200 + $232,100
$653,300
2020
$7,744 (+4.0%)
$405,800 + $232,100
$637,900
2019
$7,443 (−0.3%)
$390,500 + $187,400
$577,900
2018
$7,466 (+7.3%)
$382,900 + $171,400
$554,300
2017
$6,955 (+4.7%)
$329,300 + $171,400
$500,700
2016
$6,640 (−6.1%)
$314,000 + $171,400
$485,400
2015
$7,070 (+5.6%)
$291,000 + $179,400
$470,400
2014
$6,693 (+1.9%)
$268,000 + $179,400
$447,400
2013
$6,568 (+6.0%)
$268,000 + $179,400
$447,400
2012
$6,195 (+11.2%)
$250,800 + $179,400
$430,200
2011
$5,571 (+7.7%)
$250,800 + $149,400
$400,200
2010
$5,174 (+7.0%)
$264,200 + $124,500
$388,700
2009
$4,835
$269,200 + $125,800
$395,000
*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: 1,104
Bathroom Information
# of Full Baths: 2
Heating & Cooling
Heating Type: Forced Hot Water
Room Information
# of Rooms: 6
Exterior
Exterior Information
Physical Condition: Average
Building Style Type: Raised Ranch
Construction Type: Frame
Exterior Wall: Wood Siding/Shingle
Roof Shape Type: Gable
Property Information
Living Sq. Ft: 1,104
Gross Sq. Ft: 2,398
# of Units: 1
# of Stories: 1
Lot Information
# of Buildings: 1
Land Sq. Ft: 8,712
Municipality Name: WATERTOWN
Acres: 0.2
Zoning Code: S-6
State Use Description: 1-FAMILY RESIDENCE
Financial
Assessor Information
Assessment Year: 2026
Public facts
Beds: 3
Baths: 2.0
Sq. Ft.: 1,104
Stories: 1.0
Lot Size: 8,712 square feet
Style: Single Family Residential
Year Built: 1986
Year Renovated: —
County: Middlesex County
APN: 3695282S
Home facts updated by county records on Jul 29, 2026
Around this home
Schools
Places
Transit
Cunniff Elementary School
Public PreK-5 • Assigned • 0.4mi
8/10
Watertown Middle School
Public 6-8 • Assigned • 0.6mi
7/10
Watertown High School
Public 9-12 • Assigned • 0.6mi
6/10
Provided by GreatSchools
Lifestyle
Provided by Walk Score and Local Logic
Local insights from Redfin agents
Watertown's urban-suburban feeling paired with its proximity to Cambridge & Boston have caused it to rapidly transform into a destination for home buyers. Historically a manufacturing city, it has changed into a restaurant, shopping, and biotech hub...
with a completely built-out residential landscape.