Should I Appeal My Property Tax Assessment?
Short answer: if your assessed value looks higher than what your home would actually sell for, it's worth at least checking. The appeal process (called a "protest" in Texas) is free, the paperwork is manageable, and you do it yourself — no company taking a cut of your savings. This page helps you decide whether your situation clears the bar, and what to do next.
The Core Question: Is Your Assessed Value Higher Than Market Value?
Your assessed value is the dollar figure your local assessor (or appraisal district in Texas) placed on your property for tax purposes. Your market value is what the home would realistically sell for today. Most jurisdictions are supposed to assess at or near market value, though some use an assessment ratio (a fixed percentage of market value — for example, 80%). If your assessed value exceeds your realistic market value — or exceeds that ratio applied to market value — you likely have a case.
Pull up two or three recent sale prices for similar homes nearby (same size, age, and condition). If those comparables — often called comps — come in noticeably below your assessed value, that gap is your argument. The wider the gap, the stronger the case.
How to Estimate Your Potential Savings
Find your mill rate (dollars per $1,000 of assessed value) on your tax bill or county assessor's website. Multiply your target reduction by the mill rate to estimate annual savings. Whether the board approves a reduction — and by how much — depends on your evidence and local rules.
The Deadline Is the One Thing You Cannot Ignore
Appeal windows are typically 30 to 90 days from your assessment notice — missing the deadline means losing the chance to lower your bill for that tax year. Verify the exact current deadline with your county assessor or appraisal district.
So — Should You Appeal?
Run through this quick check:
- Comps suggest your home would sell for noticeably less than your assessed value → strong signal to appeal.
- You spot a factual error on your property record card → call the assessor's office first; a formal appeal may not be needed.
- Neighbors with similar homes are assessed lower than you (equity argument) → check whether your state allows uniformity appeals.
- You're missing an exemption (homestead, senior, veteran) → file for the exemption separately; often faster and more reliable than an appeal.
- Your assessed value already tracks or trails recent sales → appeal unlikely to help, save your time.
If the first or third point applies, the filing cost is zero and the potential upside is real — most homeowners who appeal with solid comp evidence do see at least some reduction, though no outcome is guaranteed.
The Odds, Measured: What Actually Happens to Residential Appeals
Most answers to this question are opinion. Cook County, Illinois publishes the outcome of every appeal it decides as open data, which makes it one of the few places where the odds can be counted rather than asserted. It is a single county and not a national sample, but it is a large one — and the pattern is clear enough to be useful anywhere.
| Measure, residential appeals, tax year 2024 | Figure |
|---|---|
| Appeals decided by the Board of Review | 490,231 |
| Ended in a reduction | 195,556 — 39.9% |
| Ended in an increase | 90 — 0.018% |
| Share reduced, tax year 2025 | 42.3% |
| Share reduced at the earlier Assessor stage | 21.2% |
Two numbers answer the two questions people actually have. Will it work? In roughly four cases out of ten at the stage with the better odds. Can it backfire? In 90 cases out of 490,231 — about one in 5,447. The fear of an increase is the most common reason people do not file, and it is the one concern the data most clearly does not support.
What a Reduction Is Worth, and Why That Depends on the State
A 10% reduction on a median-value home produces very different amounts depending on where it stands. The median property tax bill across the states is about $2,590; the arithmetic below uses each state's own effective rate on its own median home value.
| State | Effective rate | Median bill | Saving from a 10% reduction | Over three years |
|---|---|---|---|---|
| New Jersey | 2.23% | $9,541 | $954 | $2,862 |
| Illinois | 2.07% | $5,189 | $519 | $1,557 |
| New York | 1.60% | $6,450 | $645 | $1,935 |
| Texas | 1.58% | $4,111 | $411 | $1,233 |
| California | 0.71% | $4,926 | $493 | $1,478 |
| Florida | 0.79% | $2,555 | $256 | $766 |
| Georgia | 0.81% | $2,214 | $221 | $664 |
Why the third column matters more than it looks. Several states hold a reduced value for more than one year: Georgia normally for the two following tax years, New Jersey the same under its Freeze Act. Where that applies, the right comparison is the last column, not the one before it. Against that, a California decline-in-value reduction is temporary by design and reviewed annually. The states where the sum is largest are also, as it happens, the states where filing costs nothing: in Texas, Georgia, Illinois and New Jersey there is no fee at the first stage at all.
When It Is Honestly Not Worth It
Three situations where the answer is no, and saying so is more useful than encouragement. First, where your assessment is already below market value and protected by a cap — a long-held Florida homestead under Save Our Homes is taxed on the capped figure, and appealing achieves nothing. Second, where you cannot assemble comparable evidence: boards decide on what is put in front of them, and in Washington the owner must meet a standard of clear, cogent and convincing evidence. Third, where the gap you are arguing about is small and your state's effective rate is low — the work is the same whether the stake is $40 a year or $400.
Is It Worth It: Common Questions
What are my actual chances?
On the only large published dataset, Cook County's, 39.9% of residential appeals decided by the Board of Review for 2024 ended in a reduction, and the rate rose to 42.3% for 2025. The earlier Assessor stage reduced 21.2%. Other jurisdictions do not publish comparable figures, so treat these as indicative rather than national.
Can my assessment go up because I appealed?
It is possible in principle and rare in practice. Cook County recorded 90 increases among 490,231 residential appeals decided for 2024 — about 0.018%.
How much time does it take?
Assembling evidence is the work — a few hours to pull comparable sales and the assessor's records for nearby homes. The hearing itself is usually short, commonly under half an hour, and in many cases there is no hearing because an informal offer settles it first.
Is a small reduction worth the effort?
Multiply it by your state's effective rate and then by the number of years the reduction holds. In Georgia and New Jersey that is normally three years, which turns a modest annual figure into a number worth an afternoon. In a low-rate state with no carry-forward, it may genuinely not be.
Do I need to spend money to find out?
No. At the first stage there is no filing fee in Texas, Georgia, Illinois or New Jersey, and Florida's fee is capped at $50. Checking the assessor's published values for comparable homes nearby costs nothing and answers the question before you commit to anything.
What single factor predicts success best?
Whether comparable properties genuinely support a lower value — and whether your state lets you argue that directly. Texas allows unequal appraisal as a ground of its own; New Jersey excludes the assessments of similar properties as evidence entirely. The same facts are a strong case in one and inadmissible in the other.
Sources. Appeal outcomes are calculated from Cook County open data: the Board of Review's Appeal Decision History and the Assessor's Appeals dataset, residential class, tax years as stated. State effective rates and median bills are from the U.S. Census Bureau, American Community Survey 2019–2023 five-year estimates (tables B25103 and B25077). Carry-forward provisions are from the Georgia Department of Revenue and the New Jersey Division of Taxation; the Washington evidence standard from that state's Taxpayer Petition form 64-0075.