AppealDesk

Mercer County Property Tax Appeal, Ohio

Travis BunnTravis Bunn·Updated July 25, 2026

Mercer County is located in western Ohio along the Indiana border, with Celina serving as the county seat. With a population of approximately 42,500, the county is home to notable cities including Coldwater, St. Henry, and Fort Recovery. Mercer County's median home value of $129,600 is significantly below the national median, yet its effective property tax rate of 1.53% is notably higher than the national median of 1.02%. The county's median annual property tax bill of $1,932 remains below the national median of $2,400, making property tax appeals particularly valuable for homeowners seeking to challenge potentially inflated assessments.

Notable cities: Celina, Coldwater, St. Henry, Fort Recovery

Median Home

$129,600

Tax Rate

1.53%

Annual Tax

$1,932

Population

42,500

On the typical Mercer County home, valued near $129,600 at the county’s effective tax rate of 1.53%, an over-assessment of even 10% means you are overpaying year after year until you appeal it. Here is how to find out if yours qualifies.

2026 Appeal Deadline: March 31, 2026

This year's appeal window has passed in most of Ohio. Order now and we re-run your numbers free when the window reopens, so your evidence is ready the day your next notice lands.

For tax year 2025 assessments, property owners must file a complaint with the Mercer County Board of Revision between January 1, 2026 and March 31, 2026. The complaint must be received by the County Auditor's office or postmarked by March 31, 2026. Late filings are not accepted, and there are no extensions to this deadline set by Ohio Revised Code 5715.19.

See if your Mercer County home is over-assessed

Free analysis in 30 seconds. If the numbers support a appeal, your complete evidence packet is $49.

✓ All 50 states✓ Instant results✓ $49 flat fee
Ohio residential street of family homes. Mercer County appeal guide.

How Mercer County Assesses Property

35%of market value

Assessed by: Mercer County Auditor's Office

Assessment cycle: triennial

Notices typically mailed: April-May

In Mercer County, property taxes are calculated based on the assessed value, which is 35% of the property's market value as determined by the County Auditor. The county undergoes a triennial update every three years to reflect recent changes in the real estate marketplace. For example, if your home's market value is $129,600, at Ohio's 35% assessment ratio your assessed value would be $45,360, resulting in approximately $1,982 in annual taxes at the county's effective rate of 1.53%.

The Appeal Process

Appeals are heard by the Board of Revision. The Mercer County Board of Revision consists of three members: the County Auditor, County Treasurer, and a County Commissioner. Hearings are scheduled within 30-90 days of filing and typically last 15-30 minutes, during which you'll present your evidence to the panel.

1

Step 1: Review your assessment notice received in spring (typically April-May) and compare your property's market value to recent comparable sales in your neighborhood.

2

Step 2: Gather supporting evidence including comparable sales data, recent appraisals, photographs of property condition issues, and repair estimates documenting any defects that may reduce your property's value.

3

Step 3: Complete DTE Form 1 (Complaint Against the Valuation of Real Property) available from the Ohio Department of Taxation website or the County Auditor's office, listing your opinion of your property's true market value.

4

Step 4: Submit your complaint along with all supporting documentation to the Mercer County Auditor's office by mail or in person. The complaint must be received or postmarked by March 31, 2026.

5

Step 5: Attend your scheduled Board of Revision hearing, which will be scheduled within 30-90 days of filing. Present your evidence to the three-member panel consisting of the County Auditor, County Treasurer, and a County Commissioner representative. Hearings typically last 15-30 minutes.

6

Step 6: Receive the Board's written decision by mail, typically within 2-3 weeks after your hearing. If you disagree with the decision, you have 30 days from the date of mailing to appeal to the Ohio Board of Tax Appeals or Court of Common Pleas.

Required form: DTE Form 1 (Complaint Against the Valuation of Real Property)

Filing Methods

mail:Mercer County Auditor's Office, 101 North Main Street, Room 105, Celina, OH 45822
in-person:Mercer County Auditor's Office, 101 North Main Street, Room 105, Celina, OH 45822. Office hours: Monday 8:30am-5:00pm, Tuesday-Friday 8:30am-4:00pm

Evidence to Bring

Comparable sales from the past 3 yearsRecent independent appraisalPhotographs of property defects or condition issuesRepair estimates or contractor quotesProperty record card from County AuditorRecent purchase closing statement (if applicable)

Mercer County Assessor Contact

Mercer County Auditor's Office

Website: https://auditor.mercercountyohio.gov/

Hours: Monday: 8:30am-5:00pm, Tuesday-Friday: 8:30am-4:00pm

Tax Exemptions in Mercer County

Homestead Exemption (Senior/Disabled)

$29,000 of market value exempted (saves approximately $155 annually)

Reduces the taxable value for qualifying senior citizens (age 65+) and disabled homeowners who use the property as their primary residence.

Eligibility: Available to anyone 65 years of age and older with household income of $41,000 or less, or disabled homeowners meeting the income requirement. Must be owner-occupied primary residence.Deadline: December 31 annually

Disabled Veteran Exemption

$58,000 of market value exempted (saves approximately $310 annually)

Enhanced homestead exemption for veterans with 100% service-connected disabilities or their surviving spouses.

Eligibility: Veterans with 100% service-connected disability or surviving spouses of public service officers killed in the line of duty. No income requirement.Deadline: December 31 annually

Owner Occupancy Credit

Varies by property value

Tax reduction credit for homeowners who occupy their property as their principal place of residence.

Eligibility: Must own and occupy the home as principal place of residence as of January 1 of the tax year.Deadline: Contact County Auditor's office for details

Mercer County Appeal Packet · $49

Comparable sales evidence, county-specific filing guide, and professional cover letter. Enter your address to get started.

✓ All 50 states✓ Instant results✓ $49 flat fee

Frequently Asked Questions

What is the deadline to appeal my property taxes in Mercer County for 2026?
The deadline to appeal your 2025 property tax assessment in Mercer County is March 31, 2026. Your complaint must be filed with the Mercer County Board of Revision between January 1, 2026 and March 31, 2026. The complaint must either be received by the County Auditor's office or postmarked by the U.S. Postal Service on or before March 31, 2026. Late filings are not accepted, and there are no extensions to this statutory deadline under Ohio Revised Code 5715.19.
How do I file a property tax appeal in Mercer County?
To file a property tax appeal in Mercer County, you must complete DTE Form 1 (Complaint Against the Valuation of Real Property) and submit it to the County Auditor's office at 101 North Main Street, Room 105, Celina, OH 45822. Include your parcel number, your opinion of the property's true market value, and supporting evidence such as comparable sales or a recent appraisal. You can file by mail or in person during office hours (Monday 8:30am-5:00pm, Tuesday-Friday 8:30am-4:00pm). The form must be received or postmarked by March 31, 2026 for the 2025 tax year.
What is the homestead exemption worth in Mercer County?
The Homestead Exemption in Mercer County exempts the first $29,000 of your home's market value from property taxation for qualifying seniors (age 65+) and disabled homeowners with household income of $41,000 or less. With Mercer County's effective tax rate of 1.53%, this exemption typically saves eligible homeowners approximately $155 annually (calculated as $29,000 × 35% assessment ratio × 1.53%). Veterans with 100% service-connected disabilities qualify for an enhanced exemption of $58,000 in market value with no income requirement, providing approximately $310 in annual tax savings.
What happens at a Board of Revision hearing in Mercer County?
At a Board of Revision hearing in Mercer County, you will present your evidence to a three-member panel consisting of the County Auditor, County Treasurer, and a County Commissioner representative. Hearings are scheduled within 30-90 days of filing your complaint and typically last 15-30 minutes. You should bring your supporting evidence including comparable sales data, photographs, appraisals, or repair estimates. The Board will review your evidence and issue a written decision within 2-3 weeks after the hearing, either upholding the current assessment, reducing it, or in rare cases increasing it.
How much can I save by appealing my property taxes in Mercer County?
The amount you can save by appealing your property taxes in Mercer County depends on how much your property's assessed value is reduced. With Mercer County's effective tax rate of 1.53%, every $10,000 reduction in your property's market value translates to approximately $54 in annual tax savings (calculated as $10,000 × 35% assessment ratio × 1.53% tax rate). For example, if you successfully reduce your home's assessed value from $150,000 to $130,000, you would save approximately $107 annually. These savings continue year after year until the next reassessment.
What evidence do I need for a Mercer County property tax appeal?
For a successful property tax appeal in Mercer County, you need evidence that supports your opinion of your property's market value. The most persuasive evidence includes recent comparable sales from the past three years of similar properties in your neighborhood that sold for less than your assessed value. Other valuable evidence includes a recent independent appraisal, photographs documenting property defects or condition issues, repair estimates from licensed contractors, and your recent purchase closing statement if you bought the property within the last 12 months for less than the assessed value. Recent arm's-length purchase prices often carry the most weight with the Board of Revision.
Can I appeal my Mercer County property taxes every year?
Under Ohio law, property owners in Mercer County are generally limited to filing one Board of Revision complaint per parcel during each triennial assessment period (every three years). However, you may file an appeal in a year when you receive a notice of increased valuation, or if there has been a significant change in the property's condition such as damage or destruction. Mercer County is currently in a 2026 triennial update year, which reviews sales from 2023, 2024, and 2025, with value changes reflected on 2027 tax bills. You can also file annually if new evidence emerges or market conditions change substantially.
How does Mercer County calculate my property taxes?
Mercer County calculates property taxes by first determining your property's market value through the County Auditor's assessment process. The market value is then multiplied by Ohio's 35% assessment ratio to get the assessed (taxable) value. This assessed value is then multiplied by the local tax rate, which averages 1.53% in Mercer County but varies by location based on school district and municipal levies. For example, a home with a $129,600 market value would have an assessed value of $45,360 (35% of market value), resulting in approximately $1,932 in annual taxes at the 1.53% effective rate.

Official Resources

Mercer County Auditor's Office - Official Website →

Access property search tools, assessment information, contact details, and office hours for the Mercer County Auditor.

Ohio Department of Taxation - Property Tax Forms →

Download official DTE forms including DTE Form 1 for property tax appeals and DTE 105A for homestead exemption applications.

Mercer County Property Search Portal →

Search property records by parcel number, owner name, or address to view assessment details and tax information.

Ohio Homestead Exemption Information →

State resource providing detailed information about homestead exemption eligibility, application process, and requirements.

For state-wide appeal information including Ohio's assessment ratio and deadlines, see our Ohio Property Tax Appeal Guide →

Considering professional help with your appeal? Compare pricing, coverage, and pros/cons in our Best Property Tax Appeal Services (2026) or browse side-by-side service comparisons →

More Ohio Counties

Adams County (West Union)Allen County (Lima)Ashland County (Ashland)Ashtabula County (Jefferson)Athens County (Athens)Auglaize County (Wapakoneta)
← All Ohio property tax appeal info

Sources: https://www.appealdesk.com/appeals/ohio/mercer | https://auditor.mercercountyohio.gov/ | https://www.ownwell.com/trends/ohio/mercer-county | http://www.tax-rates.org/ohio/mercer_county_property_tax | https://www.mercercountyohio.org/elected-officials/treasurer/faq/

Last verified: 2026-07-25