Condominium at 99 Sumner St # 312, Boston MA 02128, Boston
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$999,000

99 Sumner St # 312, Boston MA 02128
Boston, MA 02128
Listed by The RP Group
Bedrooms
2
Bathrooms
2
Living area
1,085 sqft
Year built
2020

About this home

Welcome to Unit 312 at The Mark, a 1,085 sqft 2-bed, 2-bath condo offering luxury waterfront living on East Boston's waterfront. The high-end kitchen ft. stainless steel appliances, quartz countertops, and custom cabinetry flows seamlessly into a sun-filled living space w/ southeast-facing exposure. The primary suite includes a huge walk-in closet and spacious ensuite bath. Step onto your private balcony for sweeping views of Boston Harbor, the downtown skyline, and the New Year's Eve fireworks. Includes 1 garage parking spot and a storage unit. The Mark delivers resort-style amenities: 24/7 concierge, fitness center, golf simulator, pet spa, library, clubroom and lounge, and a courtyard w/ grills and firepit, all just minutes from downtown Boston.

Highlights

WaterfrontView

Property details

MLS
MLS Property Information Network
MLS #
73514835
Property type
Condominium
Subdivision
N/A
Status
Active
Days on market
160
On market date
May 7, 2026
Stories
1
Total bathrooms
2
Garage spaces
1
Parking spaces
1
Lot size
N/A
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Nearby schools

Within 10 miles. School directory data from the National Center for Education Statistics (NCES), accessed via the Urban Institute Education Data API. Local Score is calculated by INNOVATE Real Estate; where a state rating is shown, it comes from that state's own official school report card.

Elementary
Dante Alighieri Montessori School
0.34 mi away · Grades -1-6
Nearest school -- attendance-zone data not available here
5.0
Local Score (student-teacher ratio only (preliminary -- will incorporate state test-score data once available)) -- not an official state rating
Enrollment
104
Student:teacher ratio
10.4:1
District
Boston
Middle
Joseph A. Browne School
1.77 mi away · Grades 5-8
Nearest school -- attendance-zone data not available here
4.0
Local Score (student-teacher ratio only (preliminary -- will incorporate state test-score data once available)) -- not an official state rating
Enrollment
540
Student:teacher ratio
12.3:1
District
Chelsea
High
East Boston High
0.97 mi away · Grades 7-12
Nearest school -- attendance-zone data not available here
4.0
Local Score (student-teacher ratio only (preliminary -- will incorporate state test-score data once available)) -- not an official state rating
Enrollment
1,111
Student:teacher ratio
12.2:1
District
Boston

Walkability

Blended score for Boston's center, calculated by INNOVATE Real Estate from two sources: the EPA's National Walkability Index (street network, transit, land-use mix) and Google Places amenity data (what's actually reachable on foot from this point). 60% EPA National Walkability Index + 40% nearby-amenity density (Google Places).

79
Walkable
out of 100
EPA National Walkability Index
13.0 / 20 -- Above average walkable
Google Places amenity density
100 / 100
Restaurants & cafes20
Grocery stores20
Parks20
Schools20
Transit stops20
Pharmacies11

Market position

How this listing compares to current activity in Boston, from live MLS data.

On the market 160 days -- 40 more days than Boston's current average of 120 days.
For reference, the median list price across 8,758 active listings in Boston right now is $60,000.

Mortgage calculator

Estimate only - actual rate and payment depend on your lender, credit, and loan program.

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Est. monthly payment
$6,166/mo
$199,800 down
$799,200 loan
Principal & interest$5,184
Property tax (est.)$833
Home insurance (est.)$150

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Data source: Listing information provided by MLS Property Information Network via Trestle/CoreLogic. Last updated May 11, 2026.

Information herein deemed reliable but not guaranteed; all measurements, school assignments, HOA fees, taxes, and feature lists are approximate and should be independently verified. Equal Housing Opportunity.