After "does someone come to the house," the question we hear most is: does filing work? Most people know someone who got a big cut and someone who got nothing, and they figure it's luck.
The county publishes enough to settle that, so we checked.
What we counted
Every year Nassau posts the list of homes that filed a challenge. It also posts what each home was assessed at before the season and what it settled at after. Line those up and you can see, house by house, whether filing changed anything.
We did that for the last two settled cycles, 2025/26 and 2026/27, across about 300,000 homes. We left out the part of any cut the county has to grant anyway under the 6 percent cap. What's left is the part somebody asked for and got.
| 2025/26 | 2026/27 | |
|---|---|---|
| Homes that filed | 178,773 | 181,755 |
| Of those, ended up lower | 94% | 85% |
| Homes that never filed | 57,527 | 56,518 |
| Of those, ended up lower | 4% | 2% |
In 2025/26, 94 of every 100 homes that filed ended up lower. Of the homes that never filed, 4 in 100 did. 2026/27 was a tougher year, and even then a home that filed was about forty times as likely to get a cut as one that stayed home.
How big the cuts were
The bars split the homes that filed by the size of the cut, measured as a percentage of the assessment.
More than half the cuts fell between 5 and 10 percent. For a typical home that was worth about $750 a year in 2025/26 and $800 in 2026/27. Cuts over 20 percent went to 52 homes in the whole county in 2025/26, so don't plan around one.
Your town
Same numbers by town, for 2025/26. The first figure is the share of homes that filed at all. The bar splits the homes that filed by the size of the cut.
Where you live changes how many of your neighbors file. Once you file, it matters much less: in 2025/26 the no-cut share was 5 or 6 percent in all three towns. In 2026/27 it rose to 13 percent in Hempstead, 14 in Oyster Bay and 21 in North Hempstead. Even there, four homes in five that filed ended up lower.
Glen Cove and Long Beach run their own assessment offices, so they aren't shown.
Where the fewest people file
By village and hamlet, still 2025/26. First, the ten places where the smallest share of homeowners filed.
And the ten where the most did.
One home in five filed in Roosevelt, against four in five in Jericho. Once filed, about 93 in 100 got a cut in both places. The check is a different size: about $300 a year in Roosevelt and about $1,100 in Jericho, because Jericho tax bills are bigger to begin with.
If you didn't file last year
Then you're in the "never filed" row, and there's a fair chance you're paying more than the neighbor who did file. Filing can't raise your assessment. Nobody comes to the house. The next window opens January 4, 2027 and closes March 1.
Get started. It takes about a minute.
Check it yourself
The list of homes that filed comes from the Assessment Review Commission's representative data files, which the county publishes each cycle. Assessed values before and after come from the county's tentative and final rolls on its open data portal. The 6 percent cap is Real Property Tax Law section 1805.
We could match 178,773 of the 201,754 applications published for 2025/26, and 181,755 of the 221,463 for 2026/27, to a settled roll. The rest fall out on address joins or missing prior values, so the figures cover the homes we could measure. They include every home that filed, most of them through other firms, so they describe what happens to filers as a group. Our own case results are not in them. A cut counts only when it's at least one full point of assessed value beyond the cap. Typical saving is the median yearly tax on the cut, for homes that got one, at each home's own town and school rates, rounded down to $50. Villages and hamlets are grouped by the mailing address of owner-occupied homes, and we left out any place with fewer than 300 homes. These are group results. Your own house can get more, less, or nothing.