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Updated 2025 Tax Year

Sullivan County
Property Tax Guide

Everything you need to know about property taxes in Sullivan County, NH. 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
$10.85 per $1,000 of assessed value (varies by municipality and special districts)
Exemptions
6+ Available
Section 1

How Property Tax Works

Sullivan County, New Hampshire operates under a property tax system that serves as the primary funding mechanism for local services including schools, county operations, fire protection, and municipal services. Property taxes in Sullivan County are collected at the local level by individual towns and cities, with portions allocated to county government, state education funding, and local education districts. The effective tax rate varies significantly across the county depending on your specific municipality and any special taxing districts that may apply to your property.

Property tax rates in Sullivan County are expressed per $1,000 of assessed value, with the total rate for fiscal year 2025 averaging $10.85 per $1,000. This total includes county taxes ($4.74), state education taxes ($2.12), and local education taxes ($0.86), though the complete breakdown varies by municipality. Your actual tax rate will depend on which town or city your property is located in, as each municipality sets its own local portion of the tax rate and may have additional special district assessments for services like lighting districts, water districts, or special improvement areas.

Section 2

What Makes Up Your Tax Bill

ComponentRate (per $1,000)Description
County Tax$4.74Funds county government operations, sheriff's department, courthouse, county jail, and other county services
State Education Tax$2.12State-wide education funding distributed through the state adequacy formula
Local Education Tax$0.86Local school district funding varies by municipality and district
Municipal TaxVariesTown/city services including fire, police, public works, libraries (rates vary by municipality)
Total Base Rate$10.85Average total for FY 2025

Note: These rates apply to the 2025 tax year (bills due July 2025). Municipal portions vary significantly by location within Sullivan County. Additional special district assessments may apply for services such as water districts, sewer districts, or lighting districts. Contact your local assessor for your specific municipality's complete rate structure.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Sullivan 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 property tax bills in Sullivan County are issued when changes occur to property ownership, value, or tax status after the initial annual tax bills have been calculated and mailed. The most common triggers for supplemental taxes include new construction completed during the tax year, property improvements that increase assessed value, ownership transfers that affect exemption eligibility, or corrections to previously issued tax bills.

Supplemental taxes are calculated by applying the current tax rate to the difference between the original assessed value and the new assessed value, prorated for the portion of the tax year remaining. For example, if new construction worth $50,000 is completed halfway through the tax year, the supplemental tax would be calculated as: ($50,000 ÷ $1,000) × $10.85 × 0.5 = $271.25. Supplemental bills are typically mailed within 30-60 days of the triggering event and are due 30 days from the mail date, separate from your regular property tax payment schedule.

Example Calculation

Example 1: $300,000 Home

  • Assessed Value: $300,000
  • Tax Credits Applied: $0 (no credits applied)
  • Net Taxable Value: $300,000
  • Tax Calculation: ($300,000 ÷ $1,000) × $10.85 = $3,255
  • Annual Tax: $3,255
  • Monthly (if escrowed): $271

Example 2: $600,000 Home with Veterans Credit

  • Assessed Value: $600,000
  • Veterans Tax Credit Applied: -$500 (requires application - not automatic)
  • Net Tax After Credits: $6,510 - $500 = $6,010
  • Tax Calculation: ($600,000 ÷ $1,000) × $10.85 = $6,510
  • Annual Tax: $6,010
  • Monthly (if escrowed): $501

Example 3: $1,000,000 Home with Multiple Credits

  • Assessed Value: $1,000,000
  • Veterans Credit: -$500 (application required)
  • Disability Credit: -$1,400 (application required, if eligible)
  • Total Credits: -$1,900
  • Tax Calculation: ($1,000,000 ÷ $1,000) × $10.85 = $10,850
  • Annual Tax: $8,950
  • Monthly (if escrowed): $746

Note: All tax credits require separate applications and approval. Credits are not automatically applied and must be renewed periodically.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Sullivan County require property tax escrow accounts for borrowers with less than 20% down payment, though some lenders may require escrow regardless of down payment amount. Your lender collects approximately 1/12th of your estimated annual property tax bill with each monthly mortgage payment, depositing these funds into an escrow account. The lender then pays your property taxes directly to Sullivan County when they become due.

Property tax bills in Sullivan County are typically mailed in late May/early June and due July 3rd annually. Your lender should receive the tax bill and pay it by the due date to avoid penalties. Most lenders pay taxes early to ensure timely payment. You should receive an annual escrow analysis from your lender showing how much was collected, paid out, and any shortage or surplus in your account. If property taxes increase significantly from year to year, your lender may require an escrow shortage payment or increase your monthly payment to cover the higher tax amount.

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 Sullivan County property taxes due for 2025? A: Property tax bills for fiscal year 2025 were mailed on May 29, 2025, and are due July 3, 2025. This is an annual billing cycle with one payment due per year.

Q: What tax credits are available and do I need to apply? A: Sullivan County offers several tax credits including veterans credits, elderly/disabled credits, and deaf exemptions. All credits require separate applications and are NOT automatically applied. Contact your local town assessor's office to apply and determine eligibility requirements.

Q: How does the homestead exemption work? A: New Hampshire is considering homestead-type protections that would cap assessment increases rather than reduce market value. These programs, if enacted, would limit how much your assessed value can increase year-over-year (typically 5-10%) but would require annual applications.

Q: How often are properties reassessed in Sullivan County? A: Assessment schedules vary by municipality within Sullivan County. Most towns reassess every 3-5 years, though some do annual updates. Contact your local assessor for your specific town's schedule and to learn about the appeals process.

Q: What are the penalties for late property tax payments? A: Late payments in New Hampshire typically incur interest charges of 12% per year (1% per month), though specific penalty structures may vary by municipality within Sullivan County.

Q: Can I pay my property taxes online? A: Online payment options vary by municipality within Sullivan County. Check with your specific town or city hall for available electronic payment methods, which may include online portals, phone payments, or electronic checks.

Q: What special district taxes might apply to my property? A: Depending on your location within Sullivan County, you may be subject to additional assessments for water districts, sewer districts, lighting districts, or other special improvement districts. These appear as separate line items on your tax bill.

Q: How do I appeal my property assessment? A: Assessment appeals must typically be filed with your local board of selectmen or assessors within specific timeframes after receiving your tax bill. Each municipality has its own appeals process and deadlines - contact your local assessor's office for specific procedures and forms.

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
2025 Municipal Tax Ratesrevenue.nh.gov
02
Tax Doc
2025 Municipal Tax Ratesrevenue.nh.gov
03
Tax Doc
Tax Rate Data Spreadsheettax.ny.gov
04
Friday Updates - May 30, 2025 - Town of Durham, NHci.durham.nh.us
05
Finance Committee Meeting Minutesrochesternh.gov
06
State
Real Estate Processmanchesternh.gov
07
Select Board Meetingexeternh.gov
08
Tax Doc
exemptions & tax credits summary reportrevenue.nh.gov
09
2024 DP-8 Instructionsrevenue.nh.gov
10
Town of Hamptonhamptonnh.gov
All sources verified as of 2025 Tax Year

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