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  • Flats on First

    21 Charles St, Cambridge, MA 02141

    Apartment building
    1-2 beds
    Pet-friendly
    Other parking
    In-unit laundry (W/D)

    Available units

    This listing now includes required monthly fees in the total price. Learn more
    Unit
    , sortable column
    Sqft, sortable columnAvailable, sortable columnTotal price, sorted ascending
    303C
    1 bd, 1 ba
    699
    Oct 5
    $3,553
    318B
    1 bd, 1 ba
    767
    Now
    $3,694
    404C
    1 bd, 1 ba
    718
    Nov 28
    $3,728
    213B
    1 bd, 1 ba
    914
    Nov 10
    $4,453
    305C
    2 bd, 2 ba
    992
    Now
    $5,283

    What's special

    Patio
    In the mood for fresh air?
    A patio is a rare feature. Less than 14% of buildings in Cambridge have this amenity.
    Flats on First embodies the best of boutique living, combining the luxuries of a modern apartment community with the comforts of a close-knit neighborhood. Come home to a place of sophistication and serenity in East Cambridge.

    Office hours

    DayOpen hours
    Mon - Fri:10 am - 6 pm
    Sat:10 am - 5 pm
    Sun:Closed

    Facts, features & policies

    Building Amenities

    Community Rooms
    • Fitness Center: 24-Hour Fitness Center
    • Game Room
    Other
    • In Unit: Full-Size, High Efficiency Washer/Dryer
    Outdoor common areas
    • Barbecue: Grilling And Al Fresco Dining
    • Patio: Balconies*
    Security
    • Intercom: Butterflymx Intercom System
    Services & facilities
    • Bicycle Storage: Bike Storage
    • Package Service: 24-Hour Package Room
    View description
    • Roof Deck With City Views

    Unit Features

    Appliances
    • Dryer: Full-Size, High Efficiency Washer/Dryer
    • Washer: Full-Size, High Efficiency Washer/Dryer
    Flooring
    • Vinyl: Luxury, Wood-Grained Vinyl Flooring
    Other
    • Patio Balcony: Balconies*

    Policies

    Parking
    • Garage: Controlled Access Parking Garage
    • Parking Lot: Other
    Pets
    Dogs
    • Allowed
    • Dogs and Cats Restrictions: None
    Cats
    • Allowed
    • Dogs and Cats Restrictions: None

    Special Features

    • Co-working Spaces
    • Community Kitchen And Dining
    • Direct Access Entry*
    • Gourmet Kitchens With Stainless Steel Appliances
    • Groom Room
    • Landscaped Courtyards With Outdoor Seating
    • Open Air Amphitheater
    • Open Floor Plans
    • Outdoor Lounges With Fire Pits
    • Pet Friendly
    • Quartz Countertops
    • Schlage Smart Locks
    • Social Spaces With Complimentary Wifi
    • Stand-up Showers*
    • Walk-in Closets*

    Neighborhood: East Cambridge

    East Cambridge and Kendall Square pulse with innovation, offering sleek apartments, biotech offices, and trendy eateries. The vibe is modern, fast-paced, and creative. Rentals usually run $2,400–$3,000, drawing professionals and students.

    Powered by Zillow data and AI technology.

    Areas of interest

    Use our interactive map to explore the neighborhood and see how it matches your interests.

    Travel times

    Points of Interest

    Groceries

    Distance
    Whole Foods0.8 mi
    Eataly1 mi
    Bauer Wine & Spirits1 mi
    Bacco's Fine Foods1 mi
    Taza Chocolate0.9 mi
    Flats on First has 5 grocery stores within a 1 mile distance.

    Shopping

    Distance
    Uniqlo1 mi
    Trident Booksellers & Cafe1 mi
    Muji 無印良品1 mi
    Apple Boylston Street1 mi
    Lululemon Athletica1 mi
    Flats on First has 5 shopping centers within a 1 mile distance.

    Parks and recreation

    Distance
    Boston Public Garden1 mi
    SoulCycle1 mi
    Commonwealth Avenue Mall2 mi
    Barry's Bootcamp1 mi
    HealthWorks Fitness Back Bay1 mi
    Flats on First has 5 parks and recreation locations within a 2 mile distance.

    Fitness

    Distance
    Boston Public Garden1 mi
    SoulCycle1 mi
    Commonwealth Avenue Mall2 mi
    Barry's Bootcamp1 mi
    HealthWorks Fitness Back Bay1 mi
    Flats on First has 5 fitness centers within a 2 mile distance.

    Walk, Transit & Bike Scores

    97 / 100
    Walker's Paradise
    89 / 100
    Excellent Transit
    98 / 100
    Biker's Paradise

    Nearby schools in Cambridge

    GreatSchools rating

    Frequently asked questions

    What is the walk score of Flats on First?

    Flats on First has a walk score of 97, it's a walker's paradise.

    What is the transit score of Flats on First?

    Flats on First has a transit score of 89, it has excellent transit.

    What schools are assigned to Flats on First?

    The schools assigned to Flats on First include Kennedy-Longfellow School, Vassal Lane Upper School, and Cambridge Rindge and Latin School.

    Does Flats on First have in-unit laundry?

    Yes, Flats on First has in-unit laundry for some or all of the units.

    What neighborhood is Flats on First in?

    Flats on First is in the East Cambridge neighborhood in Cambridge, MA.

    Does Flats on First have virtual tours available?

    Yes, 3D and virtual tours are available for Flats on First.

    Market Trends

    Rental market summary

    The average rent for all beds and all property types in Cambridge, MA is $3,369.

    Average rent

    $3,369

    Month-over-month

    -$81

    Year-over-year

    -$26

    Available rentals

    1,941

    Cambridge, MA Rental Market Data
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