Property Tax Appeal Guide
Property tax appeals win 30–50% of the time according to data from county assessor and state appraisal-board annual reports, yet fewer than 5% of eligible homeowners file. The savings recur year over year. This is the free, six-step playbook.
The six-step process
- Get the assessor's record card. Request your property's "property record card" from the county assessor (free, online in most counties). It lists the square footage, bedroom/bath count, lot size, year built, condition rating, and any improvements they have on file. Errors here are the easiest wins — wrong square footage, wrong bath count, double-counted finished basement.
- Pull comparable sales. Find 3-5 recent sales (within 6-12 months) of similar homes (same neighborhood, ±20% square footage, similar age and condition). Use Redfin, Zillow, or your county's open sales records. Calculate each comp's price-per-square-foot.
- Compare to your assessment ratio. Your county publishes an "assessment ratio" or "common level ratio" — the percentage of market value at which they assess. If the county ratio is 80% and the comparable sales work out to $300/sqft for similar homes, your assessed value should not exceed $240/sqft for your home. If it does, you have an appeal.
- File before the deadline. Deadlines vary widely. New Jersey is January 31. Texas is May 15. California has multiple windows depending on county. Miss it and you wait until next year. Look up your county's deadline today, not later.
- Attend the hearing (or submit written evidence). Most counties offer informal review first, then formal Board of Equalization. Bring: marked-up record card showing errors, the 3-5 comparable sales with their MLS listings or sale records, a one-page summary showing your "true market value" calculation. Be factual. Don't argue what you want to pay — argue what the math supports.
- Appeal to state level if denied. Most states have a property tax court (e.g., NJ Tax Court, NY State Board of Equalization, TX SOAH). Filing fees are minimal ($50-$200). Most homeowners give up at the local board and shouldn't.
Common errors that drive over-assessment
| Error | How to find it | Typical impact |
|---|---|---|
| Wrong square footage | Compare your record card sqft to a recent appraisal or measure room-by-room | 5-15% over-assessment |
| Finished basement counted as living area | Many counties incorrectly include unfinished basement area | 3-10% |
| Wrong bath count | Half-baths counted as full; non-existent baths on record | 2-5% |
| Wrong lot size | Cross-check against deed and county GIS | 3-8% |
| Outdated condition rating | Roof leaking, kitchen not updated since 1985, foundation issues — request reassessment with photos | 10-25% |
| Improvements never actually built | Permitted addition cancelled but record never updated | varies |
| Comp set ignored neighborhood | Assessor used market-wide comps that don't reflect your micro-market | 5-15% |
What it's worth to you
A 10% reduction on a $400,000 assessment in a county with a 1.5% effective property tax rate saves $600/year. Over a 30-year hold, that compounds to roughly $18,000 in tax savings (more if you reinvest at 7%). The total time investment is typically 4-8 hours over a 2-3 month window.
Some counties also reset assessments retroactively if you win — meaning the prior 1-2 years can be refunded or credited.
Sources: International Association of Assessing Officers (iaao.org) on assessment uniformity standards; Lincoln Institute of Land Policy property tax research (lincolninst.edu); National Association of Counties tax administration data (naco.org); county-by-county appeal win-rate publications vary — verify with your local assessor's annual report.