Chappaqua is one of northern Westchester County's most established residential markets, characterized by large-lot properties, high assessed values, and a real estate market that commands premium prices. For homeowners in Chappaqua, those high assessments mean that even a modest percentage reduction in your assessed value can translate into meaningful annual tax savings — making the 2026 tax grievance filing window an important opportunity to review whether your property is assessed accurately.

If you believe your assessment does not reflect what your property would actually sell for in today's market, here is what you need to know about filing a successful tax grievance in Chappaqua.

The 2026 Filing Deadline for Chappaqua

Chappaqua is located within the Town of New Castle, and property tax grievances for New Castle follow the standard Westchester County calendar: the filing window runs from June 1 through the third Tuesday in June. Confirm the exact closing date with the Town of New Castle Assessor's office, as the third Tuesday shifts year to year.

Missing this deadline forfeits your right to challenge your assessment for the entire tax year. Given the high assessed values typical in Chappaqua, the potential savings from a successful grievance can be substantial — making early preparation critical.

Large-Lot Market with High Assessments

Chappaqua is known for its large-lot properties — homes on one, two, or even five-plus acres are common, and the market reflects a buyer pool that values space, privacy, and the character of a more rural residential environment within commuting distance of New York City. These properties command high prices, and the Town of New Castle's assessment rolls reflect those high market values.

The challenge for homeowners is that high assessed values magnify the impact of assessment error. If your property is over-assessed by 10% and your assessed value is $1.5 million, that represents $150,000 in excess assessed value — and significant annual tax overpayment.

Mass assessment methodologies in high-value markets like Chappaqua are particularly prone to error because the models are calibrated to the average property. Large-lot properties with unique features, properties with significant deferred maintenance, and properties that sold years ago at prices that no longer reflect current conditions are all at risk of inaccurate assessment.

In Chappaqua, where property values are high and lot sizes large, the dollar amount at stake in a tax grievance can be substantial. A certified appraisal gives you the strongest possible case for a reduction.

New Castle Assessment Rolls: How Your Property Is Valued

Chappaqua properties appear on the Town of New Castle assessment roll, which is updated periodically by the town assessor's office. The assessor uses a combination of recent sales data, property characteristics on file with the county, and statistical models to estimate market value for all properties in the town.

The limitation of this approach is that the assessor has not physically inspected your property recently — and in many cases, has never inspected it at all. The assessment is based on public records: the last recorded sale, the square footage and room count on file, any building permits that were recorded, and the assessor's assumptions about condition and features.

If your property has characteristics that are not captured in the public record — whether positive or negative — your assessment is likely to be inaccurate. A certified appraisal corrects for this by physically inspecting your property, documenting its actual condition, and selecting comparable sales that reflect how your specific property would be valued in today's market.

The SCAR Process in Northern Westchester

If your grievance is denied by the Board of Assessment Review, or if the reduction offered is insufficient, you can appeal through the Small Claims Assessment Review (SCAR) process in Westchester County Supreme Court. SCAR is the same process whether you are in southern or northern Westchester — it is designed to be accessible to homeowners without legal representation, and many Chappaqua residents successfully navigate it on their own.

At SCAR, a certified USPAP-compliant appraisal from an SRA-designated appraiser makes a significant difference. A hearing officer reviewing competing evidence will give substantially more weight to a professionally prepared appraisal than to informal comparable sales data. Our reports are prepared specifically to hold up at this level of scrutiny.

For a comprehensive overview of the Westchester tax grievance process, see our guide to Westchester County property tax grievances. Our tax grievance appraisal service page explains how we work with homeowners throughout Chappaqua and northern Westchester.

The SRA-Designated Appraiser Advantage

The SRA designation from the Appraisal Institute is awarded to residential appraisers who meet rigorous standards of education, experience, and ethical practice. In the context of a tax grievance, the designation signals to the Board of Assessment Review and to a SCAR hearing officer that the appraisal was prepared by a professional who holds themselves to the highest standards in the field — not simply someone who holds a state license.

Madison & Park Appraisal's principal appraiser holds the SRA designation and has completed thousands of appraisals across Westchester County, including extensive work in Chappaqua and throughout the Town of New Castle. Our reports are designed to hold up under scrutiny because they are prepared with that standard in mind from the start.

Get Started Now

Don't wait until the last week of May to start the appraisal process. A quality tax grievance appraisal for a Chappaqua property — particularly a large-lot or estate property — takes time to do well. Contact Madison & Park Appraisal today to discuss your property and get a quote. Visit our Chappaqua appraisal page for more information about our work in this area.

Frequently Asked Questions

When is the Chappaqua tax grievance deadline in 2026?

Filing runs from June 1 through the third Tuesday in June. Contact the Town of New Castle Assessor's office to confirm the exact closing date for 2026.

Do I need an appraisal to file a tax grievance in Chappaqua?

An appraisal is not required to file, but it is by far the strongest evidence you can submit. Self-prepared comparable sales data is accepted but carries significantly less weight before the Board and at SCAR.

My property is a large estate — does that make the appraisal process different?

Yes. Large-lot and estate properties require more extensive comparable sales research, careful land valuation, and often longer inspection times. An experienced appraiser familiar with the Chappaqua market is critical to a successful outcome.

What if my grievance is denied by the Board?

You can appeal through the SCAR (Small Claims Assessment Review) process in Westchester County Supreme Court. SCAR is designed to be accessible to homeowners, and a certified appraisal is the strongest evidence to bring.