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Updated 2025 Tax Year

Nassau County
Property Tax Guide

Everything you need to know about property taxes in Nassau County, NY. Rates, due dates, exemptions, and how it affects your monthly payment.

8 Official Sources
8 min read
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Quick Facts
Tax Rate
2.5% to 4.0% of market value (varies by municipality)
Exemptions
5+ Available
Section 1

How Property Tax Works

Nassau County's property tax system is among the most complex in New York State, serving as the primary funding mechanism for county services, school districts, towns, cities, villages, and special districts. Property owners in Nassau County face a multi-layered tax structure that includes county taxes, school taxes, municipal taxes, and various special district assessments. The county operates under a fractional assessment system where properties are assessed at a percentage of their full market value, with assessment ratios varying by municipality.

The effective property tax rates in Nassau County typically range from 2.5% to 4.0% of market value, making it one of the highest property tax regions in the United States. These rates vary significantly depending on the specific municipality, school district, and special districts where the property is located. The Nassau County Assessment Department oversees the assessment process, while individual municipalities handle tax collection and billing, creating a decentralized system that requires property owners to understand multiple jurisdictions' rules and procedures.

Section 2

What Makes Up Your Tax Bill

ComponentTypical Rate RangeDescription
County Tax$0.85-$1.10 per $100Funds county services including police, courts, social services, and infrastructure
School Tax$2.50-$3.50 per $100Largest component, funds local school districts
Town/City Tax$0.40-$0.80 per $100Municipal services including roads, parks, and local government
Village Tax$0.20-$0.60 per $100Additional tax for village services (where applicable)
Fire District$0.15-$0.35 per $100Fire protection and emergency services
Library District$0.10-$0.25 per $100Public library services and facilities
Special Districts$0.05-$0.20 per $100Water, sewer, lighting, and other special services

Note: Rates are expressed per $100 of assessed value and vary by specific taxing jurisdiction

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Nassau County, property taxes are due in two installments:

Pro tip: If you pay through mortgage escrow, your lender splits these payments across your monthly mortgage. If you pay directly, set calendar reminders to avoid late penalties.
Section 4

Supplemental Tax Bills

Supplemental tax assessments in Nassau County are triggered by specific events that change a property's taxable status or value during the tax year. The primary triggers include new construction or substantial improvements, changes in property use (such as conversion from residential to commercial), removal of exemptions, or ownership transfers that affect exempt status. These supplemental assessments are calculated based on the increased assessed value multiplied by the applicable tax rates for the remaining months of the tax year.

When new construction is completed or substantial improvements are made, the assessor will issue a supplemental assessment reflecting the increased property value. For example, if a homeowner completes a $100,000 addition that increases the assessed value by $80,000, and the combined tax rate is $3.50 per $100 of assessed value, the supplemental tax would be calculated as ($80,000 ÷ 100) × $3.50 × (remaining months ÷ 12). Property owners typically receive supplemental tax bills within 30-60 days of the assessment change, with payment due within 30 days of the bill date.

Example Calculation

Example 1: $300,000 Market Value Home

  • Assessed Value (60% ratio): $180,000
  • STAR Exemption: -$30,000
  • Net Taxable Value: $150,000
  • Combined Tax Rate: $3.20 per $100
  • Annual Tax: ($150,000 ÷ 100) × $3.20 = $4,800
  • Monthly Escrow: $400

Example 2: $600,000 Market Value Home

  • Assessed Value (60% ratio): $360,000
  • STAR Exemption: -$30,000
  • Net Taxable Value: $330,000
  • Combined Tax Rate: $3.45 per $100
  • Annual Tax: ($330,000 ÷ 100) × $3.45 = $11,385
  • Monthly Escrow: $949

Example 3: $1,000,000 Market Value Home

  • Assessed Value (60% ratio): $600,000
  • STAR Exemption: -$30,000
  • Net Taxable Value: $570,000
  • Combined Tax Rate: $3.65 per $100
  • Annual Tax: ($570,000 ÷ 100) × $3.65 = $20,805
  • Monthly Escrow: $1,734

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Section 5

Escrow & Property Taxes

Property tax escrow accounts are managed by mortgage lenders to ensure timely payment of property taxes throughout the year. In Nassau County, lenders typically collect 1/12th of the annual property tax bill with each monthly mortgage payment, depositing these funds into an escrow account. Due to Nassau County's complex multi-jurisdictional tax system, properties may receive multiple tax bills throughout the year from different taxing authorities, making escrow management particularly important for ensuring all obligations are met.

Lenders are required to conduct annual escrow analyses and may adjust monthly payments based on actual tax bills received and projected increases. Property owners should verify that their lender has current tax information, as changes in assessments or exemptions can significantly impact required escrow contributions. For tax payments and verification of current obligations, property owners can access Nassau County's online payment system at https://www.nassaucountyny.gov/3015/Tax-Payments, which provides detailed billing information and payment history for all county and participating municipal tax jurisdictions.

How HonestCasa Helps
  • Understand whether your escrow is set correctly
  • See how rising taxes will change your monthly payment
  • Plan ahead instead of being surprised by "shortage" letters
Section 6

Frequently Asked Questions

Q: When are property taxes due in Nassau County? A: Tax due dates vary by municipality. County taxes are typically due in two installments (October and April), while school taxes are generally due in September. Municipal taxes may have different due dates depending on your specific town or city.

Q: How do I apply for the STAR exemption? A: New applicants can apply for STAR exemptions through the New York State Tax Department online system or by contacting the Nassau County Assessment Department at https://www.nassaucountyny.gov/520/Assessment.

Q: How often are properties reassessed in Nassau County? A: Nassau County does not conduct periodic townwide reassessments. Instead, the assessment department reviews individual properties when sales occur, improvements are made, or appeals are filed.

Q: Can I appeal my property assessment? A: Yes, property owners can file assessment grievances with their local Board of Assessment Review (BAR) between February 1st and March 15th annually. Contact information is available through the Assessment Department website.

Q: What happens if I pay my property taxes late? A: Late payments incur interest charges and penalties that vary by taxing jurisdiction, typically ranging from 5-18% annually. Some jurisdictions may also charge additional collection fees.

Q: Can I pay my property taxes online? A: Yes, many Nassau County jurisdictions offer online payment options. Check the specific payment portal for your municipality or visit https://www.nassaucountyny.gov/3015/Tax-Payments for available options.

Q: What exemptions are available for senior citizens? A: Nassau County offers Senior Citizens Exemptions for qualifying property owners aged 65 and older who meet income requirements. Enhanced STAR exemptions are also available for senior homeowners.

Q: How do I obtain a copy of my property tax bill? A: Tax bills and payment history can be accessed through your municipality's tax collection office or through Nassau County's property search system. Contact information is available on the Assessment Department website.

Q: What if my mortgage company doesn't pay my taxes on time? A: Contact your lender immediately and monitor the situation. You may need to make direct payments to avoid penalties and should request documentation showing the lender's error for potential penalty relief.

Q: How are property taxes calculated for cooperative apartments? A: Cooperative buildings receive a single assessment, and the sponsor corporation pays property taxes. Individual shareholders typically pay their proportionate share through monthly maintenance fees rather than receiving separate tax bills.

Verified Sources

Backed by 8 Official Government Sources

Every fact in this guide is sourced from official county, state, and federal documents.

01
County
Nassau County Assessornassaucountyny.gov
02
County
Nassau County Assessornassaucountyny.gov
03
County
LandRecord Lookup - NassauCountyNY.govlrv.nassaucountyny.gov
04
County
LandRecord Lookup - NassauCountyNY.govlrv.nassaucountyny.gov
05
County
Nassau County - LandRecord Lookuplrv.nassaucountyny.gov
06
County
Nassau County Extends 1% Local Sales and Use Tax ...tax.ny.gov
07
State
Form TP-584.1:7/19:Real Estate Transfer Tax Return ...tax.ny.gov
08
Tax Doc
Property tax forms - Exemptions - Tax.NY.govtax.ny.gov
All sources verified as of 2025 Tax Year

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