$540,798
$9,000 since September
This home's estimate is 17.6% lower than the average sale price ($657K) of 6 comparable homes.
Claim this home to receive a free report every month with insights on the changing estimate.
Off market
$540,798
3
bd•
1 ba
•
1,496
sq ft
21 Alton St, Portland, ME 04103
About this home
21 Alton St is a 1,496 square foot house on a 5,227 square foot lot with 3 bedrooms and 1 bathroom. Based on Redfin's Portland data, we estimate the home's value is $540,798.
Single-familyProperty Type
1917Year Built
5,227 sq ftLot Size
$361Est. Price/Sq.Ft.
1 spaceParking
Source:Public Records
Redfin Estimate
Earn from this home
Sell
$507,671
Est. take-home
List your home with Redfin and save $5,408
Rent
$1,387/mo
Redfin rental estimate
List your home for rent
Market trends in 04103, ME
Last updated September 2026
Buyer's Market
Seller's Market
Seller's market
Sale-to-List Price
101.0%
1.6% MoM
Median sale price
$545K
$15K MoM
Avg. days on market
32d
18 days MoM
Recently sold homes
89
6 MoM
New listings for sale
Provided by Redfin
Property details
Around this home
Lifestyle
Provided by Walk Score and Local Logic
Sun exposure
In this area, properties receive around 8.4 hours in June and 4.2 hours in December, placing it below the U.S. average for solar exposure.
JuneDecember
Provided by Shadowmap
More real estate resources
- Cities
- Zip Codes
- Neighborhoods
- Minor Civil Divisions
- Popular Searches
| Brunswick homes for sale | |||
| Scarborough homes for sale | |||
| Cape Elizabeth homes for sale |
Find us
Subsidiaries
Affiliated Business
United States
CanadaCopyright: © 2026 Redfin. All rights reserved.
Updated September 2025: By searching, you agree to the Terms of Use, and Privacy Policy.
Do not sell or share my personal information.
REDFIN and all REDFIN variants, WALK SCORE, and the R logos, are trademarks of Redfin Corporation, registered or pending in the USPTO.
California DRE #01521930
Redfin is licensed to do business in New York as Redfin Real Estate. NY Standard Operating Procedures
New Mexico Real Estate Licenses
TREC: Info About Brokerage Services, Consumer Protection Notice
All mortgage lending products and information are provided by Rocket Mortgage, LLC | NMLS #3030; www.NMLSConsumerAccess.org. Licensed in 50 states. This site is not authorized by the New York State Department of Financial Services for mortgage solicitation or loan applications activities related to properties located in the State of New York.
Redfin Corporation is an affiliated business of Rocket Limited Partnership. Each company, and their subsidiaries, are separate legal entities operated and managed through its own management and governance structures.
If you are using a screen reader, or having trouble reading this website, please call Redfin Customer Support for help at 1-844-759-7732.
REDFIN IS COMMITTED TO AND ABIDES BY THE FAIR HOUSING ACT AND EQUAL OPPORTUNITY ACT. READ REDFIN'S FAIR HOUSING POLICY AND THE NEW YORK STATE FAIR HOUSING NOTICE.
GreatSchools Ratings provided by GreatSchools.org.