New York's 1% Property Tax Shift Cap: What Nassau and Suffolk Homeowners Should Know About S.10023

Introduction

New York's 1% property tax shift cap is back in the news, and it matters on Long Island. Six in ten Long Island homeowners have filed a property tax grievance, nearly triple the national rate of 22%. Yet many still open a bill that jumped while their assessed value barely moved.

Here's the disconnect. Your bill runs on two levers. One is your home's assessed value, which you can grieve. The other is your property class's share of the total levy.

That second lever can shift even when your own number holds steady. A bill that passed both houses of the New York Legislature in May 2026, S.10023/A.11193, would hold that shift to 1% for the 2026-27 levy. Until it is signed, it is not in effect.

Here's what we'll cover:

• What "class share" actually means for your bill

• What S.10023 would do, and where it stands

• How the rules differ for Nassau and Suffolk

• What you can do about your bill right now

Key Takeaways

• Your bill can rise even when your assessment stays flat, because your property class's share of the levy can shift.

• State law generally lets that class-share shift move up to 5% a year.

• S.10023/A.11193 passed both houses in May 2026. It hasn't been signed and isn't yet law.

• If signed, it would hold the shift to 1% for the 2026-27 roll, though the rules differ by county.

• A grievance can't change class share, but it's the one lever you control over your own assessed value.

Why Does Your Tax Bill Rise When Your Assessment Doesn't?

Your bill can rise because it depends on more than your own assessment. It also depends on how the total tax levy gets split among property classes.

New York sorts properties into separate tax classes: homes, residential rentals and condos, utility property, and other commercial property. You can read more about Nassau County's four property tax classes for the full breakdown.

Each class carries a set share of the levy, called its base proportion. This is where homestead and non-homestead base proportions matter, because the homestead base proportion reflects the residential class's tax share.

So two levers set your bill:

1. Your home's assessed value, which you can grieve.

2. Your class's share of the total levy, which you cannot grieve.

When your class's share rises, every home in that class can owe more. That can happen even if your assessed value never budged. That's the piece most homeowners never see on their bill.

This is why "my assessment didn't change" and "my bill went up" can both be true in one year. The first describes your own value. The second reflects how the levy was split across every class in your assessing unit.

What Is New York's 1% Property Tax Shift Cap (vs. the 5% Default)?

The class-share shift is how much of the levy can move from one class to another in a single year. When one class's base proportion goes up, another's goes down, and the balance decides who pays more.

State law limits that movement. Under New York's Real Property Tax Law, a class's base proportion generally cannot rise more than 5% above the prior year. New York's 1% property tax shift cap is a tighter limit that lawmakers add for covered rolls.

Here's a simplified example. Say a town collects a $100 million levy, and homes carry a 40% share, or $40 million.

• Under the 5% default, the residential share could climb to 42%, adding about $2 million to homeowners as a group.

• Under a 1% cap, that share could rise only to about 40.4%, adding roughly $400,000.

The cap doesn't erase the shift. It slows how fast the burden can move onto homeowners in a single year.

One caution matters here. A 1% cap is not permanent. It's an extension that lawmakers re-enact roll by roll, and without action, the leeway reverts to the general 5%.

What Would S.10023 Do, and Where Does It Stand?

According to the bill text of New York's S.10023, the measure would hold the class-share shift to 1% for taxes based on the 2026 assessment roll. In practical terms, that covers the 2026-27 levy.

Here's where it stands. S.10023 and its Assembly companion A.11193 passed both houses in May 2026. The Senate passed it on May 28 and the Assembly on May 29.

The Governor has not signed it. Until it is signed, it is not law and not in effect. If signed, it would keep the shift at 1% instead of letting the leeway drift toward 5%.

The framing is key. This 1% cap would not be permanent. It's an extension the legislature re-enacts roll by roll, sponsored by Sen. Monica R. Martinez with an Assembly companion carried by M. of A. Lavine.

A measure can be described with perfect accuracy and still carry zero legal effect until it is signed. So treat the 1% cap as a proposal that could shape your next bill, not a rule protecting you today.

What should you watch for?

1. First, whether the Governor signs the bill.

2. Second, which roll it applies to, since it is tied to the 2026 roll and the 2026-27 levy.

3. Third, whether a future cycle renews the 1% figure or lets it lapse to 5%.

None of that changes the one step you can take on your own assessment right now.

How Would the Cap Work in Nassau vs. Suffolk?

The cap wouldn't apply the same way everywhere. If the bill is signed, the rule that reaches you depends on your assessing unit.

That distinction matters because it changes what protection, if any, reaches your home. A Nassau County homeowner and a homeowner in a Nassau-approved assessing unit could fall under different rules for the same roll.

The filing calendars differ too. Deadlines shift year to year, so confirm the current cycle before you file. See our guide to Long Island grievance deadlines for Nassau and Suffolk for details.

What Does the Cap Fix, and What Doesn't It?

The cap addresses one thing: how fast one class's share of the levy can grow. It doesn't touch several other forces on your bill.

It does not fix equalization-rate swings between jurisdictions. According to New York State Senate materials, some Long Island homeowners saw school tax bills surge by up to 17%, an estimated $5 million increase for Suffolk homeowners in one district.

That came from an equalization-rate issue between counties. It's a different mechanism from the class-share cap, and not something S.10023 would address.

The cap also isn't the same as New York's 2% property tax levy cap. That cap limits how much a jurisdiction's total levy can grow, meaning the whole pie, not your individual bill. Your slice of that pie can still move even when the total stays within 2%.

The class-share cap doesn't change your assessed value. For that, you have one direct tool: a grievance.

When Does a Grievance Still Matter?

Even with a cap in place, your assessed value is the one lever you control. A grievance is how you challenge it. It can't change your class's share, but it can lower the value your bill is built on.

It works. In 2025, 57% of Nassau homeowners who grieved won a reduction. That was 224,983 residential properties, saving a combined $387.2 million.

In Nassau, a grievance starts with the Assessment Review Commission (ARC), the county's first level of review. If ARC doesn't resolve it, you can escalate to Small Claims Assessment Review (SCAR), a court-based second level for owner-occupied homes.

The case turns on evidence. You show that comparable homes near you sold for less than the county's estimate. Because the review looks only at your own value, a win doesn't affect anyone else's class share.

Here's what a reduction can look like. Say the county estimates your market value at $650,000, and a grievance brings it to $552,500, a 15% cut:

At Nassau County's median effective property tax rate of 0.71%, that reduction lowers the bill by $692 a year. Those savings repeat every year you hold the lower assessment. Filing is zero-risk because ARC cannot raise your assessment.

How much are you overpaying? Get a Savings Estimate.

Want to do it yourself? See how to file a Nassau County tax grievance. You can also check New York property tax exemptions like STAR to lower your bill.

How Can Ownwell Help With Your Grievance?

This is what we do every day. We handle Long Island grievances end-to-end, from filing with ARC through SCAR when the case warrants it.

Our Nassau County property tax grievance service manages the paperwork, evidence, and deadlines. Our Nassau County customers save an average of $1,462 a year, with a 93% success rate.

There's no upfront cost. In New York, we work on contingency: you pay 25% of what we save you, and only if we win. If your case goes to SCAR, we cover the $30 filing fee.

That structure keeps the risk on us, not you. We pull comparable sales, build the evidence, and track each deadline. If we don't win a reduction, you owe nothing.

What Can You Do About Your Bill Today?

The 1% cap may or may not become law this cycle. Either way, your assessed value is the lever you can act on today, and reviewing it costs you nothing.