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Why your NYC property tax bill won't match the listing

By Brian · 2026-08-28

The listing said $687 a month for taxes. The house closed at $860k, the highest price the block had seen, and the buyer built a monthly budget around that $687 because it sat right next to the price. Eighteen months later the bill was $740. Nothing about the house had changed. Nothing about the closing had triggered anything. The number on the listing was never a preview of what the buyer would pay. It was the seller's bill, for an assessment that was already behind before the sale happened.

The short answer: the listing shows the seller's bill, not yours

Every tax figure on a NYC listing is the current bill on file for the seller, computed from an assessment set under the seller's ownership. A sale doesn't trigger a new one. The city doesn't look at the price a buyer agreed to pay and set a fresh number from it. For a one-, two- or three-family home in Class 1, next year's bill starts from the same capped figure whoever holds the title.

That would be the whole story if the seller's bill were already where the city's own numbers say it should be. For most Class 1 homes it isn't. The Department of Finance publishes two figures every year for every house: what it thinks the house is worth, and what the house would be assessed at with no cap in the way. The bill is computed from a third, capped figure that sits well under that second one across most of the city. That distance is the size of the increase already queued to arrive over the next several years of capped steps, independent of what the market does next.

How the city turns a house into a number

For Class 1, the Department of Finance sets a market value once a year from a statistical model built on comparable sales in the neighborhood over the prior three years, not from what this specific house last sold for. That market value is multiplied by 6 percent, the target ratio the city has held for the whole class, producing the assessed value a house would be billed on if nothing held it back.

Something holds it back. Under Real Property Tax Law 1805, an assessor cannot raise a Class 1 parcel's billable assessed value by more than 6 percent in a year. Across five years running, the total increase is capped at 20 percent too. If a neighborhood runs hot and market value jumps 20 percent in a year, that uncapped figure jumps right along with it, while the number the bill is computed from can still move only 6 percent. The gap that opens up stays open into next year, still limited to a 6 percent step, until the billable figure finally catches up to wherever the target has drifted to by then.

None of that resets when the house changes hands, and new ownership doesn't zero out the assessment or start it over from the sale price. The house keeps climbing the same 6 percent staircase it was already on, under whoever's name is on the deed.

Co-ops and condos climb a different staircase

A co-op or condo listing's tax figure is misleading for a different reason. Class 2 buildings aren't valued off what units in them actually sold for. State law requires the city to value a co-op or condo as if it were a rental building, estimating income the building would earn even though it earns none, against a 45 percent ratio instead of Class 1's 6 percent. Classes 2, 3 and 4 also get a step Class 1 doesn't: a transitional assessed value that phases market swings in over five years before the annual caps even apply. A co-op board's own capital bills, the kind that show up as a maintenance increase rather than a tax line, run on an entirely separate schedule from any of this, and what your co-op is about to bill you for is where those come from.

How far behind, in practice

Across roughly 703k Class 1 lots on the Department of Finance's fiscal 2026 assessment roll, the median house is billed at just 4 percent of what the city says it's worth. Some of that is the target ratio itself, held at 6 percent before any cap even applies, but the ratio alone doesn't explain why the typical house is billed at only about two-thirds of that 6 percent target rather than the whole way there. One in six Class 1 homes is billed under half of its own target. Only about 3 percent have already caught all the way up.

How far behind varies by borough, tracking how fast each one's prices have run against the fixed 6 percent ceiling:

Manhattan's small stock of Class 1 houses and co-ops has the furthest left to climb, which fits: prices there have run further ahead of a fixed 6 percent ceiling than anywhere else in the city. Staten Island is closest to caught up, where price growth has been steadier year to year.

The catch-up isn't abstract. Take the citywide median, a house billed at roughly two-thirds of this year's target. Closing that gap at the maximum legal pace, 6 percent a year, works out to about six and a half years, assuming market value holds perfectly still starting today. It almost never does. A rising market pushes the target itself further out each year, so the gap usually persists instead of closing.

What to check before you build a budget

The Department of Finance mails a notice of property value each January with the coming year's market value and assessed value already on it, months before any bill goes out. That notice is where the size of a specific house's queued catch-up becomes visible, not the figure sitting on a listing that was pulled from an earlier bill. Look up any NYC address to see its market value, assessed value and tax class together on one page rather than piecing them out of separate mailings.

Reading that alongside which open violations actually follow a house to its next owner and how to spot a house that was flipped right before listing fills out what a listing's headline numbers leave out. A tax figure that looks low against the price you're about to pay usually isn't a bargain. It's a bill still partway up a staircase the sale didn't reset.