9 UNION ST
Valuation
Tax & Assessment
Property Facts
Transaction History(4)
Sales and refinances filed with the county for this home. Not every transfer is a normal sale, so check the type before comparing prices.Assigned SchoolsThe public schools this address is zoned for. Boundaries change, so confirm with the district before you count on it.
District: Boston School District
Neighborhood · ZIP 02129These are comparison scores, not percentages. 100 equals the national average, so 150 means about 50% above average.
Index scale: 100 = US average (tick). Lower is better.
Owner Tools
Data by ATTOM. Valuations are automated estimates, not appraisals. Photos from Google Street View and may not depict the current property state.
How this home compares
9 Union St measured against every home in its neighborhood, its ZIP code and its county, using county assessor records refreshed nightly. A home can stand out in one of those areas and look ordinary in another, because each one holds a different mix of homes.
- Worth more than 96% of homes in Charlestown 02129
- Costs more per square foot than 75% of homes in Suffolk County
- Bigger than 94% of homes in Charlestown 02129
- Has a bigger lot than 94% of homes in Charlestown 02129
- Older than 94% of homes in Suffolk County
What homes are worth in Charlestown 02129
Each bar is how many homes fall in that price range. The marker is this home.
This home is worth more than 96% of homes in Charlestown 02129.
How it measures up in Charlestown 02129
The dot is this home. The mark in the middle is the typical home in Charlestown 02129.
Pricier than 96% of homes nearby
Pricier than 53% of homes nearby
Bigger than 94% of homes nearby
Bigger than 94% of homes nearby
Newer than 34% of homes nearby
| Measure | This home | Charlestown 02129 | Suffolk County |
|---|---|---|---|
| Estimated valuepricier than | $2,655,778 | 96% of homes | 96% of homes |
| Price per ft²pricier than | $935 | 53% of homes | 75% of homes |
| Living areabigger than | 2,840 ft² | 94% of homes | 82% of homes |
| Lot sizebigger than | 2,842 ft² | 94% of homes | 52% of homes |
| Year builtnewer than | 1880 | 34% of homes | 6% of homes |
About 9 Union St
How much is 9 Union St, Charlestown, MA worth?
The TopHap Estimate for 9 Union St, Charlestown, MA is $2,655,778 as of Aug 30, 2026. The likely range is $2,440,641 to $2,870,915. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.
When did 9 Union St, Charlestown, MA last sell?
9 Union St, Charlestown, MA last sold on Jan 1, 1900, according to the county's recorded deed.
How big is 9 Union St, Charlestown, MA?
9 Union St, Charlestown, MA has 2 bedrooms, 3.5 bathrooms, 2,840 square feet of living space and a 0.07-acre lot.
When was 9 Union St, Charlestown, MA built?
9 Union St, Charlestown, MA was built in 1880, making it 146 years old. The building has 3 stories.
What schools serve 9 Union St, Charlestown, MA?
9 Union St, Charlestown, MA is assigned to Warren / Prescott K-8 School (elementary), rated A-; Horace Mann School For The Deaf (high). All sit in Boston School District. Attendance boundaries change — confirm with the district before relying on an assignment.
How does 9 Union St, Charlestown, MA compare to other homes in Charlestown 02129?
Among the 5,260 homes in Charlestown 02129, it is worth more than 96% of them ($2,655,778 against a typical $1,024,595), its price per square foot is higher than 53% of them ($935 against a typical $925), it is bigger than 94% of them (2,840 ft² against a typical 1,204 ft²), its lot is bigger than 94% of them (2,842 ft² against a typical 1,089 ft²) and it is newer than 34% of them (1880 against a typical 1899). Measured against all of Suffolk County, it is worth more than 96% of homes there. These shares are recounted nightly from the full county assessor record for each area, not from active listings.
What are the property taxes on 9 Union St, Charlestown, MA?
The 2025 property tax bill for 9 Union St, Charlestown, MA was $19,948. The county assessed it at $1,722,600.
More homes on Union St
- 13 Union St # 1$1.8M3 bd · 2.5 ba · 1,875 ft² · Sold $1.7M · Aug 2024
- 13 Union St # 2$1.6M2 bd · 2.5 ba · 1,750 ft² · Sold $1.4M · Jul 2023
- 11 Union St # 2$1.1M2 bd · 2 ba · 1,100 ft² · Sold $995K · Feb 2023
- 16 Union St # 1$1M2 bd · 2 ba · 1,201 ft² · Sold $975K · Sep 2022
- 16 Union St # 2$781K2 bd · 1 ba · 760 ft² · Sold $635K · Mar 2022
- 23 Union St # 4$783K2 bd · 1 ba · 714 ft² · Sold $725K · Aug 2021
- 18 Union St # 2$727K1 bd · 1 ba · 776 ft² · Sold $689K · Aug 2021
- 56 Union St # 3$1.4M2 bd · 2 ba · 1,529 ft² · Sold $1.1M · Jul 2021
- 56 Union St # 1$1.3M3 bd · 2 ba · 1,869 ft² · Sold $999K · Jan 2021
- 56 Union St # 2$1.2M2 bd · 2 ba · 1,335 ft² · Sold $899K · Jul 2020
- 31 Union St # 2$1.3M3 bd · 2.5 ba · 1,239 ft² · Sold $930K · Jun 2020
- 39 Union St # 2$1.2M1 bd · 1.5 ba · 1,194 ft² · Sold $800K · Apr 2018
Closest homes
- 11 Union St$1.2M30 ft · 2 bd · 2 ba · 1,100 ft² · Sold $535K · Aug 2003
- 11 Union St$1.1M30 ft · 2 bd · 2 ba · 1,530 ft² · Sold $525K · Nov 2011
- 11 Union St$1.1M30 ft · 2 bd · 2 ba · 1,100 ft² · Sold $995K · Feb 2023
- 114 Main St Apt 2$1.1M51 ft · 2 bd · 2 ba · 1,124 ft²
- 114 Main St Apt 3$896K51 ft · 1 bd · 1 ba · 902 ft²
- 114 Main St Apt 4$872K51 ft · 1 bd · 1 ba · 852 ft²
- 114 Main St Apt 1$1.4M51 ft · 1 bd · 2 ba · 1,656 ft²
- 116 Main St$1.1M60 ft · 2 bd · 1 ba · 936 ft² · Sold $1.1M · Jul 2023
More homes in Charlestown 02129
- 30 Monument Sq$825K1 bd · 1 ba · 885 ft² · Sold $825K · Sep 2026
- 21 Tremont St$635K1 bd · 1 ba · 681 ft² · Sold $575K · Sep 2026
- 92 Green St$550K1 bd · 1 ba · 702 ft² · Sold $550K · Sep 2026
- 30 Sackville St$829K2 bd · 2 ba · 937 ft² · Sold $855K · Sep 2026
- 27 Parker St$815K2 bd · 1.5 ba · 1,029 ft² · Sold $780K · Sep 2026
- 21 Prospect St$1M3 bd · 2 ba · 905 ft² · Sold $1M · Sep 2026
- 45 Baldwin St$656K1 bd · 1 ba · 769 ft² · Sold $550K · Aug 2026
- 5 Wallace Ct$4M4 bd · 5.5 ba · 3,233 ft² · Sold $3.9M · Aug 2026
- 106 13th St$699K2 bd · 2 ba · 978 ft² · Sold $695K · Aug 2026
- 89 School St$675K2 bd · 1 ba · 865 ft² · Sold $675K · Aug 2026
- 19 Salem St$650K1 bd · 1 ba · 745 ft² · Sold $635K · Aug 2026
- 85 School St6 bd · 3 ba · 3,294 ft² · Sold $893K · Aug 2026
Assigned schools
Explore the area
See this home in context
Open 9 Union St on TopHap’s interactive map to compare it against every sale nearby, overlay school zones and flood risk, and run a CMA.
Open in map