Is Your Property Tax Assessment Too High? Here's How to Check

Your property tax bill is only as accurate as the assessed value behind it. If your county appraisal district set your home's value too high, you are overpaying every single year until you challenge it. The National Taxpayers Union estimates that 30 to 60 percent of all properties in the United States are over-assessed, meaning millions of homeowners are paying more than they should.

But how do you know if your assessment is actually too high? Here are the key signs to look for and the steps you can take to verify.

1. Signs Your Assessment May Be Too High

• Your assessed value jumped significantly in one year. While property values do appreciate, a sudden large increase (10 percent or more) can signal an error in the appraisal district's mass valuation model.
• Your neighbors pay less for a similar home. If a comparable property on your street with the same square footage, age, and condition is assessed at a lower value, you may have an equity case.
• Recent sales in your area are below your assessed value. If homes like yours are selling for less than your appraised value, the assessment is higher than what the market supports.
• Your property records contain errors. An extra bedroom, inflated square footage, or a nonexistent pool in the county records can inflate your value.
• Your property has condition issues. Foundation problems, roof damage, flooding history, outdated electrical or plumbing systems, or other deficiencies that the appraisal district may not know about.

2. How to Compare Your Assessment

The most reliable way to check your assessment is to compare it against actual market data. Here is what to look at:

• Recent comparable sales: Find 3 to 5 homes that sold in the past 6 to 12 months within a half-mile of your property. They should be similar in size, age, bedrooms, and condition. If the median sale price is below your assessed value, you likely have a case. See our guide to comparable sales for details.
• County appraisal data: Most appraisal districts publish property data online. Look up comparable properties in your neighborhood and compare the assessed value per square foot.
• Sales ratio studies: Some states publish annual sales ratio studies that compare assessed values to actual sale prices across a county. A ratio above 100 percent means the county is systematically over-assessing.

3. What to Do If You Are Over-Assessed

If your research confirms that your assessment is too high, you have the right to file a formal protest or appeal. The specific process and terminology vary by state, but the general steps are:

1. Verify your filing deadline. Check our deadline guide for your state.
2. Gather your evidence: comparable sales, equity data, photos of property condition issues, and any corrections to your property records.
3. File your protest before the deadline using the required state or county form.
4. Attend the hearing (informal first, then formal if needed) and present your evidence clearly.

For a complete walkthrough, read our step-by-step protest guide.

Related Guides

• How to Protest Your Property Taxes: A Step-by-Step Guide (2026)
• How to Use Comparable Sales to Lower Your Property Taxes
• Property Tax Protest Deadlines by State (2026)