How to Appeal a Property Tax Assessment
A step-by-step guide to checking whether your assessment is accurate and, if not, how to formally challenge it. Also includes an assessed value vs. market value comparison widget.
Assessment vs. Market Value
Implied Market Value = Assessed Value ÷ (Assessment Ratio ÷ 100)
If the implied market value is higher than what comparable homes sell for, your assessment may be incorrect.
Assessment vs. Market Value Check
Find on your assessment notice. Common: 100% (TX, FL), 50% (MI), 40% (GA), 35% (OH), 33.3% (IL).
Recent sale price of a similar home nearby, for comparison.
Step-by-Step: How to Appeal
Review Your Assessment Notice
Every jurisdiction mails an annual assessment notice. Read it carefully for: your assessed value, the assessment date (the "valuation date" for comparables), and the deadline to appeal. Deadlines range from 30 to 90 days from the notice date and vary significantly by state.
Check the Accuracy of Your Property Record
Assessors use a property data card or record that describes your home's features (square footage, bedrooms, bathrooms, lot size, year built, quality grade). Errors here — an extra bedroom, a finished basement that was never built, the wrong square footage — can inflate your assessed value. Request your property record from your county assessor and compare it to your home's actual characteristics.
Research Comparable Sales
Gather 3–5 arm's-length sales of similar properties (similar size, age, condition, location) that sold near your county's assessment date. Your county's assessment roll, the MLS (ask a real estate agent), or public sale records at the county recorder's office are reliable sources. Use the implied market value widget above to see whether your assessed value aligns with what comparable homes are selling for.
Try an Informal Review First
Most assessors offer an informal review before a formal appeal. Call or visit your assessor's office, present your evidence (property record errors, comparable sales), and ask whether they will reduce your assessment. Many assessments are corrected at this stage at no cost and with no formal filing.
File a Formal Appeal (Grievance / Petition)
If the informal review doesn't resolve the issue, file a formal appeal with your local Board of Assessment Review, Board of Equalization, or Appraisal Review Board (the name varies by state). Most states provide a standard appeal form. File before the deadline — late filings are typically rejected with no exceptions.
Bring: your property record card (highlighting errors), comparable sales data, photographs documenting condition issues, and if applicable, a recent appraisal.
Attend the Hearing
Be factual and specific. Present your comparables clearly — ideally a table showing each comparable's address, sale date, sale price, and key characteristics alongside your property. Avoid emotional arguments about tax burden; stick to evidence that your property's assessed value exceeds its market value.
Further Appeals (If Needed)
If the board upholds your assessment, most states allow further appeal to a state-level tax court or circuit court. Time limits and filing fees apply. At this stage, a property tax attorney or certified appraiser is often worthwhile for higher-value properties.
State-Specific Appeal Information
Appeal deadlines and procedures vary — always verify with your state's official resources.
All links verified June 2026 against official state .gov sources.
Frequently Asked Questions
Market value is the estimated price your property would sell for between a willing buyer and seller. Assessed value is the value your county assessor assigns for tax purposes — it is often a percentage of market value (the assessment ratio). If your assessed value is higher than what your property would actually sell for, you may have grounds to appeal.
Compare your assessed value to recent sales of similar properties in your neighborhood. If comparable homes sold for less than the value implied by your assessment (market value = assessed value / assessment ratio), your assessment may be inflated. Check sales data from your county assessor, the MLS, or sites like Zillow or Redfin — but confirm comparables with your county.
In most jurisdictions you do not need a lawyer for an informal review or first-level formal appeal. Some homeowners hire property tax consultants (who often work on contingency) for complex cases or higher-value properties. Many state boards of review process appeals without attorneys.
You are typically required to pay your tax bill (or at least the undisputed portion) while your appeal is pending, to avoid penalties and interest. If your appeal succeeds and your assessed value is reduced, you usually receive a refund or credit for the overpaid amount.
The most persuasive evidence is a recent, arm's-length sale of your own property at a lower price than the assessed value implies. If you have not recently sold, comparable sales data (at least 3–5 similar homes that sold near the assessment date) and, for higher-value properties, a professional appraisal are the strongest forms of evidence.