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Flats on First

21 Charles St, Cambridge, MA 02141

Visit www.flatsonfirstapts.com
(617) 915-3502
$2,757 - $10.1k
Total price
Studio - 2
Beds
1 - 2
Baths
This listing now includes required monthly fees in the total price. Learn more
Costs & fees breakdown

Highlights

  • Apartment Building
  • Cats and dogs allowed
  • In-unit washer / dryer
  • Lot, garage
  • Patio
  • Intercom
  • Gym
  • Updated 3 hours ago

Apartment floor plans

This listing now includes required monthly fees in the total price. Learn more
MatchesStudio1 Bed2 Beds
Studio
1 bath439 sqft
Total price / mo
Available
Unit
$2,757
Now
316B
$2,757
Now
217B
$3,016
6/2/2026
605B
$3,016
7/24/2026
617B
Studio
1 bath584 sqft
Total price / mo
Available
Unit
$3,141
Now
410B
$3,216
Now
612B
1 bed
1 bath757 sqft
Total price / mo
Available
Unit
$3,974
5/19/2026
619B
1 bed
1 bath794 sqft
Total price / mo
Available
Unit
$4,074
7/16/2026
604B

Commute

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About Flats on First

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.

Apartment amenities

Property amenities
  • Barbecue
  • Bicycle Storage
  • Co-Working Spaces
  • Community Kitchen And Dining
  • Direct Access Entry*
  • Dryer
  • Fitness Center
  • Flooring: Vinyl
  • Game Room
  • Garage
  • Gourmet Kitchens With Stainless Steel Appliances
  • Groom Room
  • Landscaped Courtyards With Outdoor Seating
  • Laundry: In Unit
  • Open Air Amphitheater
  • Open Floor Plans
  • Outdoor Lounges With Fire Pits
  • Package Service
  • Parking Lot
  • Patio
  • Patio Balcony
  • Pet Friendly
  • Quartz Countertops
  • Schlage Smart Locks
  • Security: Intercom
  • Social Spaces With Complimentary Wifi
  • Stand-Up Showers*
  • View Type: Roof Deck With City Views
  • Walk-In Closets*
  • Washer

Pet policy

Cats allowed
  • 2 pets max
  • 100 lbs max
  • Cat
Dogs allowed
  • 2 pets max
  • 100 lbs max
  • Dog

Office hours at Flats on First

Sunday: Closed
Monday: 10:00 AM to 6:00 PM
Tuesday: 10:00 AM to 6:00 PM
Wednesday: 10:00 AM to 6:00 PM
Thursday: 10:00 AM to 6:00 PM
Friday: 10:00 AM to 6:00 PM
Saturday: 10:00 AM to 5:00 PM

Nearby schools

9
8
8
Students who live in Flats on First attend the following Cambridge School District (Unified School District) public schools:
AllPrimaryMiddle
Showing 2 of 10 schools.
GreatSchools ratings are based on test scores and additional metrics when available.
(617) 915-3502
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Frequently asked questions

How many apartment units are available and what are their rents?

  • There are 6 studio apartments available starting at $2,757
  • There are 3 one-bedroom apartments available starting at $3,974
  • There are 2 two-bedroom apartments available starting at $5,384

What is the apartment building's pet policy?

There are cats and dogs allowed at Flats on First. Please contact the property manager for up to date pet policy and fee information.

Is there laundry in the building?

This building offers in unit laundry.

Does the building offer parking?

Yes, Flats on First provides parking.

What Cambridge neighborhood is Flats on First in?

Your new apartment would be located in the East Cambridge neighborhood.

What school district is this building in?

Flats on First is within the Cambridge School District. Check out the additional Nearby Schools for more boundary details.

When was this listing last updated?

The property manager updated this rental listing 3 hours, 59 minutes ago.