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Updated 2025 Tax Year

Nantucket County
Property Tax Guide

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

10 Official Sources
8 min read
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Quick Facts
Tax Rate
Varies by classification; residential typically $12-15 per $1,000 assessed value
1st Due
Aug 1
2nd Due
Nov 1
Exemptions
5+ Available
Section 1

How Property Tax Works

Nantucket County, Massachusetts operates under a property tax system that serves as the primary funding mechanism for local government services, including education, public safety, infrastructure maintenance, and municipal operations. The county follows Massachusetts state property tax guidelines while maintaining local control over assessment practices and exemption programs. Property owners in Nantucket face some of the highest effective tax rates in Massachusetts, reflecting both the island's unique geography and high property values.

The property tax system in Nantucket County is administered at the town level, with the Town of Nantucket being the primary municipality. Tax rates vary based on property classification, with residential, open space, and commercial properties subject to different rates. The system includes a Community Preservation Act surcharge, which adds approximately 3% to the base tax rate to fund affordable housing, historic preservation, and open space initiatives. Property owners should be aware that most exemptions and credits require annual application and are not automatically applied to tax bills.

Section 2

What Makes Up Your Tax Bill

ComponentFY 2025 Rate (per $1,000)FY 2026 Rate (per $1,000)Description
Residential Base Rate$3.11$2.96Standard residential property tax rate
Residential Total Rate$3.28$3.12Includes Community Preservation Act surcharge
Open Space Rate$3.11$2.96Properties classified as open space
Commercial Rate$5.56$5.29Commercial and industrial properties
Community Preservation Surcharge~3% of base~3% of baseFunds affordable housing, historic preservation, open space

Note: Rates are subject to annual adjustment by the Board of Selectmen and may vary slightly based on final budget approval and state certification. The FY 2026 rates show a decrease from FY 2025 levels.

Section 3

When Are Property Taxes Due?

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

First Installment
Aug 1
Delinquent after Dec 10
Second Installment
Nov 1
Delinquent after Apr 10
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 taxes in Nantucket County are additional property tax assessments issued when there are changes to property ownership, value, or use that occur after the annual assessment date but before the end of the tax year. Common triggers include new construction completion, property transfers that remove exemption eligibility, or significant improvements that increase assessed value. The supplemental tax is calculated by applying the current tax rate to the difference between the new assessed value and the previously assessed value, prorated for the remaining months in the tax year.

For example, if a property completes $200,000 in renovations in September and the residential tax rate is $3.28 per $1,000, the supplemental tax would be approximately $656 ($200,000 ÷ 1,000 × $3.28) prorated for the remaining 8 months of the fiscal year, resulting in a supplemental bill of about $437. Supplemental taxes are billed separately from regular quarterly payments and typically have a 30-day payment deadline from the issue date.

Example Calculation

Example 1: $300,000 Assessed Value (Primary Residence)

  • Assessed Value: $300,000
  • Residential Exemption Applied: $82,797 (25% of average residential value)
  • Net Taxable Value: $217,203
  • Annual Tax: $217,203 ÷ 1,000 × $3.28 = $712
  • Monthly Escrow: $59

Example 2: $600,000 Assessed Value (Primary Residence)

  • Assessed Value: $600,000
  • Residential Exemption Applied: $82,797 (25% of average residential value)
  • Net Taxable Value: $517,203
  • Annual Tax: $517,203 ÷ 1,000 × $3.28 = $1,696
  • Monthly Escrow: $141

Example 3: $1,000,000 Assessed Value (Secondary Home)

  • Assessed Value: $1,000,000
  • Residential Exemption Applied: $0 (not primary residence)
  • Net Taxable Value: $1,000,000
  • Annual Tax: $1,000,000 ÷ 1,000 × $3.28 = $3,280
  • Monthly Escrow: $273

Note: Residential exemption requires annual application and proof of primary residence.

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Section 5

Escrow & Property Taxes

Property tax escrow accounts are commonly required by mortgage lenders in Nantucket County due to the high property values and tax amounts. Lenders typically collect 1/12th of the estimated annual property tax bill with each monthly mortgage payment, depositing these funds into an escrow account. The lender then pays property taxes directly to the Town of Nantucket when quarterly bills are due. Nantucket follows a quarterly billing cycle with due dates typically falling on August 1, November 1, February 1, and May 1, though specific dates may vary slightly each year.

Homeowners should verify that their lender has current contact information with the Town Assessor's office and review their annual escrow analysis statement to ensure adequate funds are being collected. Given Nantucket's rapidly changing property values, escrow shortages or surpluses are common and may require adjustment to monthly payments. Property owners can monitor their tax bills and escrow payments through the Town's online portal to ensure timely payment and avoid potential late fees or interest charges.

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 Nantucket County for FY 2025? A: Property taxes are due quarterly on August 1, November 1, February 1, and May 1. Each bill covers three months of the fiscal year, and late payments incur interest charges.

Q: What is the residential exemption and how do I apply? A: The residential exemption reduces your assessed value by up to 35% of Nantucket's average residential value (currently 25% or $82,797 for FY 2025). You must occupy the property as your primary residence and file an annual application with the Assessor's office by the deadline.

Q: Are there other tax credits available? A: Yes, veterans, elderly residents, and disabled persons may qualify for additional exemptions. Each requires a separate application and proof of eligibility. Contact the Assessor's office for specific requirements and deadlines.

Q: How often are properties reassessed? A: Nantucket conducts regular assessment updates to maintain fair market values. Property owners receive assessment notices annually and can appeal during the designated appeal period if they disagree with their assessed value.

Q: What happens if I pay my taxes late? A: Late payments incur interest charges at the rate set by Massachusetts law (currently 14% annually). Additional penalties may apply for significantly delinquent accounts.

Q: Can I pay my property taxes online? A: Yes, the Town of Nantucket offers online payment options through their official website. Various payment methods are accepted, though convenience fees may apply for credit card payments.

Q: How does the Community Preservation Act surcharge work? A: The 3% surcharge is added to your base tax rate and funds local affordable housing, historic preservation, and open space projects. Some exemptions may apply for low-income residents.

Q: What if I disagree with my property assessment? A: You can file an abatement application with the Board of Assessors within the designated appeal period, typically three months from the tax bill date. Provide comparable sales data or professional appraisal to support your case.

Verified Sources

Backed by 10 Official Government Sources

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

01
Tax Doc
Tax Rate History Chart (PDF)nantucket-ma.gov
02
Tax Doc
Massachusetts Tax Ratesmass.gov
03
Town of Nantucket - 2025 Annual Town Meetingnantucket-ma.gov
04
IMPORTANT DATESnantucket-ma.gov
05
Tax Doc
Tax Billing Schedule | Nantucket, MA - Official Websitenantucket-ma.gov
06
Town Collection | Nantucket, MA - Official Websitenantucket-ma.gov
07
Residential Exemption | Nantucket, MA - Official Websitenantucket-ma.gov
08
Frequently Asked Questions - CivicPlus.CMS.FAQnantucket-ma.gov
09
Frequently Asked Questions - CivicPlus.CMS.FAQnantucket-ma.gov
10
Town of Nantucketnantucket-ma.gov
All sources verified as of 2025 Tax Year

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