Property Tax Guide

How Much Can You Save by Appealing Your Property Taxes?

Published September 14, 2026

Before you spend an afternoon on a property tax appeal, it's fair to ask what it's worth. How much can you save by appealing your property taxes? You can work out the real figure for your own home in a few minutes, and it turns on four numbers you can find or estimate.

The short version: your savings are the value reduction you can actually prove, times the tax rate that applies to that value, times the number of years the lower value stands, minus what it costs to get there.

#	The number	Where it comes from
1	The reduction you can prove	The county's market value vs. comparable sales
2	The tax rate on that value	Last year's bill, or the rate printed on it
3	How many years it lasts	How often your area reassesses
4	What it costs	Filing fee, your time, any consultant's share

Step 1: The reduction you can prove, not the one you hope for

Start with the gap between the market value your county set and what comparable homes near you actually sold for. That gap is the ceiling on your savings, and a hearing can land anywhere at or below it. A reduction you can't support with three or four closed sales is worth nothing on paper, however high the number on your notice feels. If you haven't measured the gap yet, check whether your home is over-assessed first. Everything below builds on that number.

Step 2: Multiply by the tax rate, on the right basis

The fastest honest estimate uses your effective tax rate: last year's total tax bill divided by the market value the county gave your home that year. A $6,000 bill on a home valued at $400,000 is an effective rate of 1.5%. Multiply your proven market-value reduction by that rate:

Market-value reduction	At a 1% effective rate	At 1.5%	At 2%
$10,000	$100 a year	$150 a year	$200 a year
$25,000	$250 a year	$375 a year	$500 a year
$50,000	$500 a year	$750 a year	$1,000 a year

These figures are illustrations, not averages. Effective rates vary widely from one city to the next, so use your own bill.

The mistake to avoid is mixing bases. Many bills print a rate in mills (dollars per $1,000), and in states that tax a fraction of market value, that rate applies to the smaller assessed figure, not the market value. Say your state assesses homes at 25% of market value and your rate is 60 mills. A $40,000 market-value reduction lowers your assessed value by $10,000. At 60 mills, that saves $600. That's the same answer the 1.5% effective rate gives, because 25% of 60 mills is 15 mills, or 1.5%. Apply 60 mills to the full $40,000 and you'd predict $2,400, four times too high. Divide your bill by market value, or convert the reduction to assessed value first. Either way works; mixing the two doesn't.

One refinement: if you have a flat exemption, the effective-rate shortcut slightly understates what each dollar of reduction saves, because the exemption already shrank last year's bill. For a precise number, apply the printed rate to the change in assessed value.

Step 3: Multiply by the years the lower value stands

A reduction doesn't always vanish after one bill. Some places revalue every year, so next year's value is set fresh and a win may cover only one bill, though some states limit how much a value lowered on appeal can be raised in the years that follow. Others hold values steady between reassessments, so a lower value can carry forward until the next one. In that case, the $600 in the example above is worth about $1,800 over three years. How often your area reassesses is the difference between a small win and a meaningful one, so find out before you weigh the effort.

What can shrink your savings to zero

• An assessment cap. Several states limit how fast taxable value can rise. Suppose the county says your home is worth $400,000, but a cap holds its taxable value at $330,000. If you prove it's really worth $360,000, this year's bill doesn't change, because the cap was already below your new number. Whether the lower market value helps in later years depends on how your state's cap works, so don't count on an instant cut.
• Exemptions and credits. A flat exemption comes off before the rate is applied, so it doesn't change what each dollar of reduction saves. But if an exemption, freeze, or credit already removes most of your bill, there's little left to cut.
• A board that raises values. In many states, the board hearing your appeal can move the value up as well as down. The expected value of an appeal isn't just what you could save. It's what you could save, weighed against what you could lose.

What it costs to get there

Some jurisdictions charge a filing fee and many don't, so check yours. Then count your time: pulling comparable sales, filling out the form, and possibly attending a hearing. Many property tax consultants work on contingency, keeping a share of the tax savings they win. That can make sense for a large, complicated case. On a $600-a-year savings, it means handing over part of a win you could document yourself.

Is the gap even big enough to argue?

Mass appraisal values thousands of homes at once, and the professional standard for it builds in a margin. The IAAO's Standard on Ratio Studies, approved in 2013, treats an average dispersion (the coefficient of dispersion, or COD) of 5 to 10 percent as acceptable for single-family homes in newer, similar neighborhoods, and 5 to 15 percent in older, more varied ones. A revised draft released for comment in 2026 updates those ranges, but the 2013 version remains IAAO's recommended guidance until a final one is approved. In plain terms, individual homes routinely sit several percent above or below the typical assessment level, even when the county is doing its job well.

That's why a small gap is rarely worth filing. It's hard to win, and even a win saves little. A gap in the low double digits, backed by comparable sales you can defend one at a time, is where the arithmetic above starts producing real money.

Putting it together

Take your proven reduction, multiply by your tax rate on the right basis, and multiply by the years the lower value is likely to stand. Then check the three things that can zero it out: a cap, an exemption, and whether the board can raise you. All three depend on where you live. Your state's property tax appeal guide covers the assessment ratio, the cap, the deadline, and the raise rule together.

This is the math PROppeal is built around. It pulls licensed comparable sales for your address, applies your state's ratio and cap rules, and puts a dollar figure on what a successful appeal is worth. Sometimes the honest answer is that it isn't worth filing.

Property tax rules and deadlines vary by jurisdiction and can change — verify with your county before relying on this.