Multi-Year Trends

How has Chemung County's tax base changed from 2021 to 2025? Five years of assessment data across all municipalities and property types.

Five-Year Snapshot
The county's total assessed value grew by $785 million — a 14.6% increase — while the median single-family home assessment rose from $85,900 to $100,700.
$5.36B Total assessed value — 2021
$6.14B Total assessed value — 2025
+14.6% County-wide assessed value growth
$85,900 → $100,700 Median single-family assessment
+17.2% Median single-family growth
How property assessment works in New York — the plain version: Every property in the county has two numbers attached to it: the assessed value (what the local assessor says it's worth for tax purposes) and the market value (what it would actually sell for). These are not the same number, and they don't have to be — but ideally, one is a consistent fraction of the other.

Some towns reassess every year and keep their numbers close to market value. Others — like the City of Elmira — haven't done a serious update in decades, so their assessed values are far below what homes are actually selling for. Elmira homes are assessed at roughly 56 cents on the dollar of actual market value. Horseheads is closer to 80 cents. This makes direct comparisons across towns tricky.

When the state calculates school and county taxes — which cross town lines — it applies a correction factor to level the playing field. That correction is what produced the apparent jump in Elmira's numbers in 2023. It did not change what any individual homeowner was assessed at. It changed how the state counts Elmira's roll when dividing up shared tax bills.

County Overview
Total assessed value, median single-family home value, and assessed vs. full market value gap — each plotted year by year.
County assessment trends 2021–2025
County Assessment Trends, 2021–2025 Left: total assessed value across all parcels. Center: median assessed value for single-family (class 210) parcels. Right: the gap between assessed and full market value for median single-family homes — the shaded area shows how much value is not yet captured in the tax roll.

Growth by Municipality
Which municipalities grew fastest — and which added the most total assessed value? Towns of Ashland and Baldwin are excluded: both are largely state forest land with minimal private development, making them statistical outliers.
Municipal assessment growth 2021–2025
Municipal Assessment Growth: 2021 → 2025 Left: percent change in total assessed value — shows which places are growing fastest relative to their own base. Right: absolute dollar change — shows where the largest new wealth is accumulating in the county.

Growth by Property Type
Not all property types are growing at the same pace. Single-family homes dominate parcel counts, but commercial and industrial properties can shift the tax base significantly even with fewer parcels.
Assessment growth by property class 2021–2025
Assessment Growth by Property Type, 2021–2025 Left: indexed total assessed value (2021 = 100) — tracks the trajectory of each category year by year. Right: cumulative percent change from 2021 to 2025 for each category.

What This Means
Single-family homes are carrying more of the tax base over time. The +17% median assessment growth since 2021 outpaces the overall county average of +14.6%. As homeowners see higher assessed values, they bear a larger share of the total tax levy unless commercial and industrial assessments keep pace.
The assessed-vs-market gap matters for fairness. In the right panel of the overview chart, the shaded area between assessed and full market value represents wealth that exists in the county but isn't yet reflected in tax bills. When municipalities reassess and close that gap, assessed values rise — sometimes sharply — even when actual market prices haven't changed much.
Big Flats and Horseheads lead in absolute dollars. The Route 17 commercial corridor — Arnot Mall, big-box stores, warehousing — concentrates a large share of high-value commercial property in those two municipalities. Their dollar gains dwarf smaller towns even when percentage growth is comparable.

Data: NYS ORPTS assessment rolls via data.ny.gov, dataset 7vem-aaz7. Years 2021–2025. Each roll year represents values as of the assessment date for that year. See Data & Methods for full methodology.