Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Expected net benefit (probability-weighted)
$585
Annual tax savings if successful
$900
Payback period on appeal cost
1.00
Expected ROI on appeal cost
65%
Total savings over the period, if won
$2,700
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How to use this
- 1Enter current assessed value ($).
- 2Enter target assessed value after appeal ($).
- 3Enter effective property tax rate (%).
- 4Enter appeal cost (filing + appraisal/attorney) ($).
- 5Enter estimated chance of success (%).
- 6Enter years until next reassessment.
- 7Read your expected net benefit (probability-weighted) on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Appealing a property tax assessment costs time and sometimes money — a filing fee, and often an appraisal or attorney fee if you hire help — against a savings that recurs every year the reduced assessment holds, typically until the next reassessment cycle. This calculator estimates your likely savings from a successful appeal and nets it against the appeal cost to show payback period and multi-year ROI, since a modest one-time cost that saves you money for three or four years until the next reassessment is usually a strong return even on a fairly small annual dollar amount.
Worked example
Using the values the calculator loads with:
Inputs
- Current assessed value: 340000 $
- Target assessed value after appeal: 290000 $
- Effective property tax rate: 1.8 %
- Appeal cost (filing + appraisal/attorney): 900 $
- Estimated chance of success: 55 %
- Years until next reassessment: 3
Results
- Expected net benefit (probability-weighted): $585
- Annual tax savings if successful: $900
- Payback period on appeal cost: 1
- Expected ROI on appeal cost: 65%
- Total savings over the period, if won: $2,700
What each field means
Inputs
- Current assessed value ($)
- The current assessed value used in the calculation, measured in $. Starts at 340000 $ so you have a working example on load.
- Target assessed value after appeal ($)
- The target assessed value after appeal used in the calculation, measured in $. Starts at 290000 $ so you have a working example on load.
- Effective property tax rate (%)
- The effective property tax rate used in the calculation, measured in %. Starts at 1.8 % so you have a working example on load. Accepted range: 0–6 %.
- Appeal cost (filing + appraisal/attorney) ($)
- The appeal cost (filing + appraisal/attorney) used in the calculation, measured in $. Starts at 900 $ so you have a working example on load.
- Estimated chance of success (%)
- The estimated chance of success used in the calculation, measured in %. Starts at 55 % so you have a working example on load. Accepted range: 0–100 %.
- Years until next reassessment
- The years until next reassessment used in the calculation. Starts at 3 so you have a working example on load. Accepted range: 1–10.
Results
- Expected net benefit (probability-weighted)
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Annual tax savings if successful
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Payback period on appeal cost
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Expected ROI on appeal cost
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total savings over the period, if won
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What's a realistic chance of winning a tax appeal?
Success rates vary by jurisdiction and how strong your comps are, but many assessors' offices report 40-60% of appeals result in at least a partial reduction, especially when the appellant brings solid comparable sales evidence. A well-documented appeal with a recent independent appraisal or clear comps performs much better than a vague complaint that taxes are too high.
Is it worth hiring a tax appeal firm?
Many charge a contingency fee (commonly 25-50% of the first year's savings) with no upfront cost, which removes your downside risk entirely and can be worth it if you don't have the time or comps knowledge to build a strong case yourself. For a straightforward case with clear comps, filing yourself often nets more of the total savings.
How long does a reduced assessment last?
It depends on your jurisdiction's reassessment cycle — some counties reassess annually, others every 2-5 years, and a few only on sale or major improvement. A shorter reassessment cycle reduces the total multi-year benefit of winning an appeal, since the assessor may reset the value again soon.
Does a successful appeal affect resale value?
No — assessed value for tax purposes and market value for sale purposes are different numbers, and a lower assessment doesn't signal a lower market value to buyers. If anything, lower carrying costs from reduced property tax can make the property marginally more attractive to income-focused buyers.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Property Tax Appeal ROI Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/property-tax-appeal-roi
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/property-tax-appeal-roi" target="_blank" rel="noopener">Property Tax Appeal ROI Calculator — RevenueLab</a> (2026).</p>
Source: [Property Tax Appeal ROI Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/property-tax-appeal-roi) (2026).