Residential Assessment Ratio (RAR) — how it works and why grievance firms care

Assessors declare a Level of Assessment — but those declarations can be optimistic or out of date. The RAR is NY State’s independent measurement based on actual sales: if assessors claim properties are assessed at 100% of market value, but homes are selling for 20% more than their assessed values, the RAR will say 83% (= 100/120).

The State publishes the RAR for every assessing unit (every town in NY) on tax.ny.gov.

1. NY State collects all verified residential sales in a town over the past 1-3 years
2. For each sale, divides the property’s assessed value (as of valuation date) by the sale price
3. The median of those ratios is the RAR

If a town’s assessor is keeping up with the market, the RAR closely matches the declared Level of Assessment. If the market is rising faster than reassessment, the RAR drops below the LoA — and savvy homeowners can use this gap in grievance arguments.

NY State law allows you to grieve based on either the declared LoA or the State’s computed RAR, whichever is lower. Lower ratios produce higher implied market values, which (counterintuitively) actually weakens over-assessment claims.

So: if you’re grieving residential property and the RAR is HIGHER than the LoA, use the RAR. That’s a weaker over-assessment case for you — but it’s the math the State expects.

More commonly: if the RAR is LOWER than the LoA (i.e., the State thinks properties are more under-assessed than the Town claims), you may have a weaker case for grieving. But this is rare; usually the RAR aligns closely with declared LoA on Long Island.

The practical upshot: look up the RAR for your town, plug your assessment into the formula, see what implied market value the State thinks your home has. Compare to recent comparable sales. If the comps are below the implied market value, you have a grievance case.