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Updated 2025 Tax Year

Mercer County
Property Tax Guide

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

9 Official Sources
8 min read
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Quick Facts
Tax Rate
1.5%-2.5% of assessed value (varies by school district, municipality, and township)
Exemptions
5+ Available
Section 1

How Property Tax Works

Mercer County, Ohio operates under the state's property tax system, where real estate taxes fund essential local services including schools, libraries, townships, municipalities, and county operations. Property owners pay taxes based on their property's assessed value multiplied by the effective tax rate for their specific location within the county. The Ohio Department of Taxation conducts property revaluations every six years, with the most recent countywide reappraisal affecting tax year 2024.

Effective property tax rates in Mercer County typically range from approximately 1.5% to 2.5% of assessed value, though actual rates vary significantly by location due to different combinations of school districts, municipalities, townships, and special taxing districts. Each property's total tax rate consists of multiple levies from various local government entities, including the county general fund, school districts, emergency services, libraries, and any applicable special assessments for infrastructure improvements or other municipal services.

Property taxes in Mercer County are collected in two installments annually, with specific due dates set by the County Treasurer. The tax year runs from January 1 to December 31, and taxes are typically paid in the year following the assessment year.

Section 2

What Makes Up Your Tax Bill

ComponentApproximate Rate RangeDescription
County General3-5 millsBasic county operations and services
School Districts25-35 millsLocal school district operations and bonds
Township/Municipality2-8 millsLocal government services (varies by location)
Library1-2 millsPublic library system funding
Emergency Services1-3 millsFire, EMS, and emergency dispatch
Special Assessments0-5 millsInfrastructure, TIF districts, special projects
Total Effective Rate32-58 millsVaries significantly by taxing district

Note: These rates apply to tax year 2024 (collected in calendar year 2025). One mill equals $1 per $1,000 of assessed value. Actual rates vary by specific location within Mercer County based on the combination of taxing districts that serve each property. Contact the Mercer County Auditor's office for exact rates applicable to your specific address.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Mercer 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 Ohio are rare compared to some states, as the property tax system operates on an annual assessment cycle. However, supplemental assessments may occur when significant improvements are made to a property mid-year, such as new construction completion, major additions, or substantial renovations that increase the property's assessed value. When supplemental taxes are levied, they are calculated based on the increased assessed value multiplied by the applicable tax rate, prorated for the portion of the tax year the improvement was in place.

For example, if a homeowner completes a $50,000 home addition that increases their assessed value by $35,000 (at Ohio's 35% assessment ratio) in July, they would owe supplemental taxes on that additional $35,000 of assessed value for half the tax year. At a 45-mill effective rate, this would result in approximately $788 in supplemental taxes ($35,000 × 0.045 × 0.5 years). These supplemental bills are typically issued separately from regular tax bills and have their own due dates.

Example Calculation

Example 1: $300,000 Home

  • Market Value: $300,000
  • Assessed Value (35%): $105,000
  • Less: Homestead Credit (if eligible): $25,000 reduction cap
  • Net Taxable Value: $80,000-$105,000 (depending on credits)
  • Annual Tax (45 mills): $3,600-$4,725
  • Monthly Escrow: $300-$394

Example 2: $600,000 Home

  • Market Value: $600,000
  • Assessed Value (35%): $210,000
  • Less: Homestead Credit (if eligible): $25,000 reduction cap
  • Net Taxable Value: $185,000-$210,000
  • Annual Tax (45 mills): $8,325-$9,450
  • Monthly Escrow: $694-$788

Example 3: $1,000,000 Home

  • Market Value: $1,000,000
  • Assessed Value (35%): $350,000
  • Less: Homestead Credit (if eligible): $25,000 reduction cap
  • Net Taxable Value: $325,000-$350,000
  • Annual Tax (45 mills): $14,625-$15,750
  • Monthly Escrow: $1,219-$1,313

Note: All tax credits require separate application and approval. Homestead credits limit assessment increases rather than providing dollar-for-dollar reductions. Actual tax rates vary by specific taxing districts.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Mercer County require borrowers to maintain an escrow account for property tax payments, particularly when the loan-to-value ratio exceeds 80%. Lenders collect monthly escrow payments as part of your mortgage payment, then remit taxes directly to the Mercer County Treasurer on your behalf. The escrow amount is calculated by dividing your annual property tax bill by 12, often with an additional buffer to account for potential tax increases.

Property tax payments in Mercer County are collected in two installments annually. The first half payment is typically due in February, while the second half is mailed by June 20th and due by July 20th of each year. Lenders usually pay both installments on time to avoid penalties and interest charges. Property owners should verify that their lender has current mailing address information with the County Treasurer to ensure tax bills are received promptly.

If you pay taxes directly (without escrow), you'll receive tax bills from the Mercer County Treasurer's office. It's important to notify both your lender and the County Treasurer if you pay off your mortgage or change escrow arrangements, as this affects how and when tax bills are delivered and processed.

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 Mercer County for 2025? A: For tax year 2024 (collected in 2025), the first half payment is typically due in February 2025, and the second half is mailed by June 20, 2026, with payment due by July 20, 2026.

Q: What tax credits are available and do I need to apply? A: The Homestead Exemption is available to homeowners 65+ or totally disabled, but requires application with the County Auditor. The Owner-Occupied Credit may be available for primary residences. Most credits are NOT automatic and require separate applications with specific deadlines.

Q: How does the Homestead Credit work? A: The Homestead Credit limits annual assessment increases rather than reducing market value. It caps assessment growth and requires annual filing with the County Auditor by the first Monday in June. This is a credit that reduces your tax liability, not an exemption that reduces assessed value.

Q: How often are properties reassessed in Mercer County? A: Ohio conducts countywide property revaluations every six years. The most recent reappraisal affected tax year 2024. Informal appeals can be filed with the County Auditor, and formal appeals go to the Board of Revision.

Q: What are the penalties for late property tax payments? A: Ohio law imposes penalties and interest on delinquent property taxes. Interest accrues monthly on unpaid balances, and properties can eventually face foreclosure proceedings for extended non-payment.

Q: Can I pay property taxes online in Mercer County? A: Check with the Mercer County Treasurer's office for current online payment options and accepted payment methods. Many Ohio counties offer online payment systems for property taxes.

Q: Why do tax rates vary within Mercer County? A: Tax rates differ based on your specific combination of taxing districts, including school district, township or municipality, library district, and any special assessments. Each location has a unique combination of these service providers.

Q: How do special district taxes affect my bill? A: Special districts for services like fire protection, lighting, or infrastructure improvements add mills to your total tax rate. These appear as separate line items on your tax bill and vary by location within the county.

Verified Sources

Backed by 9 Official Government Sources

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

01
County
General Information - Mercer County Auditorauditor.mercercountyohio.gov
02
County
MERCER COUNTY, OHIOohioauditor.gov
03
County
310386000000 - County Auditor, Mercer County, Ohioauditor.mercercountyohio.gov
04
County
Home - County Auditor, Mercer County, Ohioauditor.mercercountyohio.gov
05
Tax Doc
Property Tax – Real Propertydam.assets.ohio.gov
06
Tax Doc
Property Tax – Real Propertydam.assets.ohio.gov
07
Tax Doc
Property Tax – Real Propertytax.ohio.gov
08
County
FINANCIAL CONDITION MERCER COUNTY SINGLE ...ohioauditor.gov
09
House Bill 335 Committee Activity | 136th General Assemblylegislature.ohio.gov
All sources verified as of 2025 Tax Year

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