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Updated 2025 Tax Year

Williamson County
Property Tax Guide

Everything you need to know about property taxes in Williamson County, TN. 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
$1.30 per $100 assessed value (county base rate), varies significantly by special taxing districts
Exemptions
4+ Available
Section 1

How Property Tax Works

Williamson County, Tennessee operates a property tax system that serves as the primary funding source for essential local services including public schools, law enforcement, fire protection, road maintenance, and county administration. The county's fiscal year 2025-2026 budget totals $702,428,992, supported largely through property tax revenue. Property taxes in Williamson County are calculated using the assessed value of your property multiplied by the applicable tax rate, which varies significantly based on your specific location within the county.

The effective tax rate in Williamson County varies considerably due to multiple special taxing districts that overlay the base county rate. While the county general fund rate is $1.30 per $100 of assessed value, your total tax rate depends on which municipal boundaries, school districts, and special service districts apply to your property. This means two properties with identical assessed values can have substantially different tax bills based solely on their location within the county.

Property assessments in Tennessee are conducted by the county assessor, with properties typically reassessed every four to six years. The assessed value represents the property's fair market value as of the assessment date, and Tennessee does not impose a statewide assessment cap, though certain tax credits may limit annual assessment increases for qualifying homeowners.

Section 2

What Makes Up Your Tax Bill

ComponentRate (per $100)Description
County General Fund$1.30Base county operations and services
School DistrictsVariesFunding for local school systems (varies by district)
Municipal RatesVariesCity services (if within city limits)
Special DistrictsVariesFire districts, utility districts, other special services
Total Composite Rate$0.413776 - $4.00+Combined rate varies significantly by location

Rates shown are for fiscal year 2025-2026. The composite rate of $0.413776 per $100 represents one specific tax district combination, while actual rates throughout the county range from this amount to over $4.00 per $100 of assessed value depending on your property's location and applicable special districts.

Note: Your specific tax rate depends entirely on which taxing jurisdictions your property falls within. Properties in incorporated areas with multiple special districts will have significantly higher rates than unincorporated areas with minimal special districts.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Williamson 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 taxes in Williamson County are additional property tax assessments that occur when there are changes in property ownership, completion of new construction, or significant property improvements during the tax year. These taxes are calculated on a pro-rated basis from the date of the triggering event through the end of the current fiscal year.

The most common trigger for supplemental taxes is new construction or major improvements that increase a property's assessed value. When the county assessor identifies these changes, they calculate the difference between the old and new assessed values, apply the current tax rate, and pro-rate the additional tax based on the remaining months in the fiscal year.

For example, if you complete a $100,000 home addition in October and your tax rate is $2.50 per $100, the supplemental tax would be calculated as: ($100,000 × $2.50 ÷ $100) × (9 months remaining ÷ 12 months) = $1,875. This supplemental bill is issued separately from your regular annual property tax bill and typically has its own payment deadline.

Example Calculation

Example 1: $300,000 Property

  • Market Value: $300,000
  • Assessed Value: $300,000 (100% of market value)
  • Less: Homestead Credit: -$18,750 (assuming 25% assessment growth cap applied)
  • Net Taxable Value: $281,250
  • Annual Tax: $281,250 × ($2.50 ÷ $100) = $7,031
  • Monthly Escrow: $586

Example 2: $600,000 Property

  • Market Value: $600,000
  • Assessed Value: $600,000
  • Less: Homestead + Elderly Credit: -$37,500 (combined credits, applications required)
  • Net Taxable Value: $562,500
  • Annual Tax: $562,500 × ($3.00 ÷ $100) = $16,875
  • Monthly Escrow: $1,406

Example 3: $1,000,000 Property

  • Market Value: $1,000,000
  • Assessed Value: $1,000,000
  • Less: Homestead Credit: -$25,000 (assessment growth limitation)
  • Net Taxable Value: $975,000
  • Annual Tax: $975,000 × ($3.50 ÷ $100) = $34,125
  • Monthly Escrow: $2,844

Note: All tax credits require annual application and approval. Rates used are examples as actual rates vary by specific location within the county.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Williamson County require borrowers to maintain an escrow account for property tax payments, especially for loans with less than 20% down payment. Your lender collects monthly escrow payments along with your principal and interest, then pays your property tax bill directly to the county when taxes become due on January 31st.

Lenders typically collect escrow payments based on the previous year's tax bill plus a small cushion (usually 1-2 months) to account for potential increases. Since property tax bills in Williamson County are typically issued in October for the following January due date, there can be timing mismatches between when your actual tax amount is known and when your lender has collected sufficient escrow funds. This may result in escrow shortages that require additional payments or increases to your monthly escrow amount.

It's important to verify that your lender pays your property taxes on time, as you remain ultimately responsible for timely payment even when using an escrow account. You can check payment status on the Williamson County Tax Assessor's website or contact the tax office directly. If your lender fails to pay on time, you may face interest charges and penalties that could affect your credit rating.

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 Williamson County property taxes due for fiscal year 2025-2026? A: Property taxes are due by January 31, 2026. Tangible personal property taxes (Schedule B) are due by March 1, 2026. Payments postmarked by these dates are considered timely.

Q: What homestead tax credit is available and how do I apply? A: The homestead credit limits annual assessment increases rather than reducing your property's assessed value. This credit caps assessment growth and requires annual application through the County Assessor's office. Applications typically must be filed by a specific deadline - contact the assessor for current application deadlines and requirements.

Q: Are there other tax credits available that require application? A: Yes, Williamson County offers several tax credits including elderly/disabled credits and veteran credits. All credits require separate applications and documentation. Unlike exemptions that reduce assessed value, credits directly reduce your tax bill. Contact the County Assessor's office for specific eligibility requirements and application deadlines.

Q: How often are properties reassessed and can I appeal my assessment? A: Williamson County conducts property reassessments every 4-6 years, though the assessor can adjust values annually based on market changes or property improvements. Assessment change notices are typically mailed by May 20th. You have the right to appeal your assessment through the Board of Equalization if you believe it's incorrect.

Q: What penalties apply for late property tax payments? A: Interest and penalties accrue on unpaid property taxes after the January 31st deadline. Contact the Tax Collector's office for current penalty rates and interest calculations, as these can compound monthly and significantly increase your total amount due.

Q: Can I pay my property taxes online? A: Yes, Williamson County accepts online payments via credit card or e-check, though convenience fees may apply. Payments made electronically may not immediately reflect in your account history. The county's website provides secure payment options and account lookup services.

Q: Why do property tax rates vary so much within Williamson County? A: Tax rates vary significantly based on which special taxing districts your property falls within, including school districts, municipal boundaries, fire districts, and utility districts. Two identical properties can have vastly different tax bills based solely on their location and applicable special districts.

Q: How do special districts affect my property tax bill? A: Special districts provide specific services like fire protection, schools, or utilities, and each adds its own tax rate to your bill. Your total tax rate is the sum of all applicable district rates. The County Assessor can provide information about which districts apply to your specific property address.

Verified Sources

Backed by 10 Official Government Sources

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

01
County
2025 Williamson County Property Tax Rateswilliamsoncounty-tn.gov
02
County
Property Tax Rates | Williamson County, TN - Official Sitewilliamsoncounty-tn.gov
03
County
Williamson County Approves FY25-26 Budget and Sets ...wilcotx.gov
04
Important Dateswilliamsoncounty-tn.gov
05
Tax Doc
Payment Options - Property Taxwilcotx.gov
06
County
Property Assessor | Williamson County, TN - Official Sitewilliamsoncounty-tn.gov
07
County
Williamson County Tn Property Taxnacdashboard.nara.gov
08
County
Williamson County Property Taxesnacdashboard.nara.gov
09
County
Property Data Search | Williamson County, TN - Official Sitewilliamsoncounty-tn.gov
10
Tax Doc
How to Calculate Your Tax Billcomptroller.tn.gov
All sources verified as of 2025 Tax Year

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