Revaluations: when they aren't, and when they go wrong

What the law says a revaluation is

Real Property Tax Law § 102(12-a):

“‘Revaluation’, ‘reassessment’ or ‘update’ means a systematic review of the assessments of all locally assessed properties, valued as of the valuation date of the assessment roll containing those assessments, to attain compliance with the standard of assessment set forth in subdivision two of section three hundred five of this chapter.”

Two words carry the weight: all properties, and the standard in § 305(2) — one uniform percentage of value for everyone.

The State's rules for towns on a regular reassessment cycle say what that takes. The plan must “provide for a reappraisal of all parcels at least once every four years,” and “Reappraisal means developing and reviewing a new determination of market value for each parcel.” (20 NYCRR 8201-3.3.) The State's Office of Real Property Tax Services describes every reassessment as a systematic analysis in which “all assessments are compared to the current market and adjusted as necessary” (ORPTS, reassessment methods).

When a “revaluation” is not a revaluation

Only some properties were changed

Reassessing the homes that sold, the homes that were improved, or one neighbourhood — and leaving the rest of the roll alone — is not a revaluation. It is a selective reassessment, and New York courts have struck it down again and again:

• Matter of Krugman v Board of Assessors of Vil. of Atlantic Beach, 141 AD2d 175 (2d Dept 1988): reassessing only homes that sold. “This approach lacks any rational basis in law and results in invidious discrimination between owners of similarly situated property.”
• Matter of Towne House Vil. Condominium v Assessor of Town of Islip, 200 AD2d 749 (2d Dept 1994): “there was no rational basis in law for reassessing only the subject property.”
• Matter of Stern v Assessor of City of Rye, 268 AD2d 482 (2d Dept 2000): homes brought to full market value after they were bought and improved, when only the value of the improvements could be added — “Since no comprehensive assessment plan was in place to reassess the entire tax roll to reflect the comparable market value of all appreciated properties.”
• Matter of DeLeonardis v Assessor of City of Mount Vernon, 226 AD2d 530 (2d Dept 1996), and Matter of Weiner v Board of Assessors of Town/Vil. of Harrison, 69 AD3d 949 (2d Dept 2010): the same result for a purchase-price reassessment in Mount Vernon and a post-renovation reassessment in Harrison.

In the Town of Fort Ann, owners alleged that lakefront neighbourhoods were reappraised while the rest of the town was only adjusted by a percentage. The trial court refused to dismiss their case (Pettersen v Town of Fort Ann, 23 Misc 3d 549 [Sup Ct, Washington County 2008]); the appeal was later dismissed as moot because the town carried out a town-wide reassessment in 2009.

Everything was moved by one percentage

Raising or lowering every assessment by the same factor (“trending”) keeps every existing error exactly where it was. The State allows trending only for groups of properties that already show “acceptable to good uniformity”; where they do not, “a reappraisal must be conducted regardless of whether assessments are at the desired level” (ORPTS). For the State's higher level of reassessment aid, “The use of trending as the sole means of establishing a new market value for any parcel will not be considered a reassessment” (ORPTS Publication 1028).

The limits, stated honestly

Two things cut the other way. First, an owner who claims a selective reassessment still needs proof: in Matter of Carroll v Assessor of City of Rye, 123 AD3d 924 (2d Dept 2014), the owner lost because “The petitioner failed to submit any evidence demonstrating that the City assessed newly constructed property at a higher percentage of market value than existing property.” Second, in Small Claims Assessment Review the method is not the question — the result is. “[R]egardless of the propriety of the methodology,” owners are “not entitled to any relief in their small claims review proceeding unless that assessment is in fact excessive or unequal” (Matter of Bellomo v Board of Assessment Review, 185 AD2d 574 [3d Dept 1992]). That is why I measure the result: your assessment against your value and against your neighbours'.

Towns that stay at 100% without a revaluation

Many towns show an equalization rate of 100 — meaning, on paper, that property is assessed at full market value. Most homeowners assume that means their assessment is right. It does not necessarily mean that.

How a town keeps its 100

• The 5% test. Each year the State compares the town's stated level of assessment with its own estimate. If they are “5% or less different,” the town's stated level is accepted as the equalization rate (Market Value Survey Procedure for 2026 State Equalization Rates). A town that says 100 keeps 100 if the State's measure lands roughly between 95 and 105.
• The window after a reassessment. A “Reassessment municipality means any municipality that completed a reassessment for the 2023, 2024, 2025 or 2026 roll year.” For those towns the State does not reappraise parcel by parcel; it carries the reassessment's values forward using “aggregate market adjustment factors” that are regional and by property type (same procedure).
• No uniformity score. In the State's own equity data, towns in that window are marked “Review of Reassessment,” and the field notes say they “are deemed equitable due to their recent reassessment” (data.ny.gov, Assessment Equity Statistics). In the 2024 survey all 184 towns at 100 were in that category, and in 2025 all 178 — none of them has a published coefficient of dispersion, the State's measure of how evenly homes are assessed.

The State says so itself: “Equalization rates do not indicate the degree of uniformity among assessments within a municipality” (ORPTS Publication 1121).

What the State's own numbers have shown

In years when the State did measure uniformity, some towns at 100 were far from uniform. The coefficient of dispersion (COD) is the average percentage by which individual assessments miss the typical level; the State's guideline for all property is under 20 in rural towns and under 15 in the densest places. The price-related differential (PRD) shows whether cheaper homes are assessed more heavily than expensive ones; the acceptable range is 0.98 to 1.03 (2025 assessment equity report).

Each is at 100 on paper, with residential assessments scattered well beyond the State's guideline and tilted against lower-value homes. The opposite also happens: in 2022 the Town of Corinth (Saratoga) had an equalization rate of 100, but the State measured its residential level at 84.41 and published that as its residential assessment ratio.

Source: data.ny.gov datasets 4sut-q3dt (equity statistics) and bsmp-6um6 (residential assessment ratios), retrieved 21 September 2026.

What it means for a homeowner

• A rate of 100 measures the average, not fairness. Half the homes can be over-assessed and half under-assessed and the average still comes out at 100.
• The ratio test stops working. The usual quick proof of an unequal assessment divides your assessment by the State's residential assessment ratio. If the ratio is 100, that shows nothing. The proof has to come from the assessor's own records — above all the Comparable Assessments Report, which shows how similar homes on the same roll are assessed. The hearing officer is directed to consider “the assessment of comparable residential properties within the same assessing unit” (RPTL § 732(2)). How to get it.
• An excessive-assessment claim is direct. At 100%, an assessment above what the house would sell for is excessive under RPTL § 522(4)(a). Your purchase price or an appraisal is the evidence.
• The hearing officer chooses the measure. In Matter of Barringer v Town of Newburgh, 2025 NY Slip Op 05680 (2d Dept 2025), a hearing officer used the State equalization rate instead of the residential assessment ratio, and the court held “her decision to apply the SER over the RAR had a rational basis and was not arbitrary and capricious or an error of law.” But the officer must actually deal with the evidence: in Matter of Heredia v Assessor of Inc. Vil. of Freeport, 2025 NY Slip Op 25121 (Sup Ct, Nassau County 2025), owners showed with a ratio study that the village's real level was below the State's figure; the court annulled 41 denials because “the Hearing Officer does not provide the basis of her determinations regarding Petitioners' unequal assessment claims; in fact, said claims are not addressed at all.”

Check your own town

The State publishes everything above: equity statistics (COD and PRD by town, by year), residential assessment ratios, and equalization rates. Or call me and I will pull them for you.

Revaluations that went wrong

In the courts

In the news

• Nassau County, 2018–2020. After nearly a decade of frozen values, the county's reassessment drew more than 253,000 grievances (CBS New York, May 2019), and a state court let a lawsuit over it proceed as a class action for roughly 400,000 homeowners (Long Island Press, February 2020).
• Town of Potsdam, 2025. After a $385,000 town-wide revaluation, some assessments rose by as much as 144% (others went down); owners complained of no on-site visits, wrong square footage and missing or outdated features (Watertown Daily Times, March 2025; April 2025).
• City of Hudson, 2019. The Common Council voted to reject the revaluation's preliminary assessments and asked the mayor to end the contract; the mayor had vetoed the same measure (WGXC, April 2019).
• City of Rochester, 2024. Assessments rose 68.4% overall and 136% in one neighbourhood; four Council members asked for the reassessment to be halted (WXXI, February 2024).
• City of Syracuse, 2019. With no citywide revaluation since 1996, a newspaper analysis found higher-priced homes generally sold above their assessments and lower-priced homes below them — a system it called “tilted against the poor” (The Post-Standard via Governing, September 2019).
• Outside New York. Detroit over-assessed homeowners by an estimated $600 million after the recession, with lower-value homes hit hardest (Citizens Research Council of Michigan; public radio, 2020). In Cook County, Illinois, a study found flawed assessments shifted about $2.2 billion in taxes onto over-assessed homes from 2011 to 2015 (ProPublica, 2018).

The pattern repeats: bad inventory data, too few sales behind the values, and a formula that loads the burden onto modest homes. Each of those can be tested against the town's own records.

Assessor fraud

Most assessors are honest people doing a hard job. But assessment power is real money, and these cases show what happens when the records are not checked.

Each entry reports only what the cited prosecutor, agency or news organisation reported, including how the case ended.

What this means for you

• A recent “revaluation” or an equalization rate of 100 does not prove your assessment is right.
• The test is always the same: your assessment as a share of your home's value, against everyone else's share on the same roll.
• The proof is in the assessor's own records — the Comparable Assessments, Comparable Sales and Cost Valuation Reports and your property record card — and you are entitled to them. Here is how.

Call 315-876-2262 for a free analysis.