423 Union Ave
Mamaroneck, NY 10543
5 bd 2 ba 2,168 sqft Built 1910 Lot 8,699 sqft multi_family
No recorded sales
Location
Timeline: Sale, Listing & Tax History
Recorded events
No recorded events
No sale or listing events are on file for this property.
Tax assessment history
| Year | Building | Land | Total assessed | Tax paid |
|---|---|---|---|---|
| 2025 | $581,700 | $443,000 | $1,024,700 | $20,131 |
| 2024 | $383,300 | $443,000 | $826,300 | $19,291 |
| 2023 | $334,800 | $421,900 | $756,700 | $14,345 |
| 2022 | $272,300 | $421,900 | $694,200 | $14,135 |
| 2021 | $272,300 | $421,900 | $694,200 | $18,492 |
| 2020 | $266,200 | $335,300 | $601,500 | $16,416 |
| 2018 | $237,000 | $328,900 | $565,900 | $16,654 |
| 2017 | $259,500 | $325,800 | $585,300 | $15,249 |
| 2016 | $285,100 | $304,500 | $589,600 | $19,293 |
| 2015 | $206,900 | $263,900 | $470,800 | $16,060 |
| 2014 | $206,900 | $255,100 | $462,000 | $19,169 |
| 2013 | $204,100 | $255,100 | $459,200 | $157,136 |
| 2012 | $267,600 | $255,100 | $522,700 | $17,481 |
| 2011 | $394,700 | $220,200 | $614,900 | $2,676 |
| 2008 | $456,400 | $258,600 | $715,000 | $11,041 |
| 2007 | $451,400 | $258,600 | $710,000 | $8,057 |
Property facts
Year built
1910
Property type
multi_family
Stories
—
Beds
5
Baths
2
Living area
2,168 sqft
Lot size
8,699 sqft
ZIP code
10543
City
Mamaroneck
Street
Union Ave
Coordinates
40.95492, -73.73320
Comparable properties nearby
Frequently asked questions
When did 423 Union Ave last sell?
No public-record sale is on file for 423 Union Ave.
What is the current tax assessment for 423 Union Ave?
The most recent total assessment for 423 Union Ave (year 2025) is $1,024,700 with $20,131 in property tax.
When was 423 Union Ave built?
423 Union Ave was built in 1910.
How does 423 Union Ave compare to others on Union Ave?
We track 5 other properties on Union Ave. Browse the list under "Other properties on Union Ave" to compare beds, baths, and sale history.
What are the property facts for 423 Union Ave?
423 Union Ave is a 5 bed, 2 bath, 2,168 sqft, 8,699 sqft lot multi_family.
Is 423 Union Ave a flip candidate?
No — 423 Union Ave does not appear in our flips dataset.
Is 423 Union Ave a tax-appeal candidate?
No — 423 Union Ave is not currently flagged as a tax-appeal candidate.
Forecast for this area
ZIP-area linear projection — not a per-property automated valuationQuarterly trend
-6.8%
Implied 1-yr
-27.2%
2026 Q3
$693.8K
2026 Q4
$693.8K
ZIP 10543 — Median Price History + Forecast
Explore nearby
Geography
Other properties on Union Ave