New Trier Township Property Tax Appeal Results & Success Rates
In New Trier Township's 2025 reassessment, 3,479 of 11,156 homeowner appeals ended with a change — a 31.2% success rate, counting each appeal once — and winning homeowner appeals cut assessed value about 7.9% on average. About three in ten appeals moved the number, but outcomes varied a lot by property class, which is why the right comps and details matter.
(2025, each counted once)
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The Short Version
- 3,479 of 11,156 New Trier homeowner appeals won a change — a 31.2% success rate, roughly three in ten, counting each appeal once.
- Winning homeowner appeals cut assessed value about 7.9% on average; the typical (median) cut was about $9,480.
- Property class shaped the odds: high-volume single-family classes clustered in the 27%–35% range, condo appeals lagged near 14%, and small commercial led at 54%.
- These are 2025 reassessment-year results — New Trier is in the north suburban group, reassessed in 2025 with the next reassessment due in 2028. Reassessment years draw the most appeals and the strongest outcomes.
- You don't have to wait: New Trier's 2026 appeal window closed on June 22, 2026.
This post summarizes how property tax appeals turned out in New Trier Township for the 2025 tax year — the township's most recent reassessment. In Cook County, a successful appeal usually means the assessed value was adjusted after review, often because the evidence supported a lower value than what the Assessor proposed. New Trier shows a meaningful number of successful outcomes, but not most cases — which is exactly why understanding the patterns by property class, and bringing the right comps, matters.
Data Overview
These figures come from Cook County Assessor appeal records for New Trier Township (township code 23), tax year 2025 — the township's reassessment year. Each appeal is counted once: a condo building's units, decided together, are one appeal.
| Homeowner appeals (each appeal counted once) | 11,156 |
| Successful appeals (marked "Change") | 3,479 |
| Homeowner success rate | 31.2% |
| Average cut, winning homeowner appeals | ~7.9% |
| Typical (median) cut, winning homeowner appeals | $9,481 |
Overall Success Rate
The homeowner appeal success rate in New Trier Township was 31.2%. Counting each appeal once, 3,479 of 11,156 homeowner appeals ended with a "Change" — counted here as a successful appeal, meaning the proposed assessed value didn't stay the same after review. A simple way to think about it: roughly three out of ten appeals in this group ended with a change.
That's a strong rate, and it's consistent with a reassessment year — fresh values create the most room for correction, so both filings and reductions run higher than in off years. If your assessment feels too high, the results suggest it's worth checking the basics first — property details, comparable sales, and your classification — before filing.
Success Rate by Property Class
Property class matters because Cook County class codes describe what a property is. Most Class 2 codes are residential — single-family homes in various sizes and ages, plus condos and townhomes — and New Trier's volume is overwhelmingly single-family. Sorted by class, the pattern is clear.
| Class | What it generally represents | Appeals | Success |
|---|---|---|---|
| 2-06 | Older two-or-more story home, 2,201–4,999 sq ft | 3,965 | 31.9% |
| 2-99 | Residential condominium | 66* | 13.6% |
| 2-78 | Two-or-more story home, 2,001–3,800 sq ft | 1,584 | 26.8% |
| 2-04 | One-story home, 1,801+ sq ft | 1,082 | 35.4% |
| 2-05 | Older two-or-more story home, up to 2,200 sq ft | 1,035 | 32.9% |
| 2-09 | Older two-or-more story home, 5,000+ sq ft | 943 | 30.1% |
| 2-08 | Two-or-more story home, up to 2,000 sq ft | 789 | 31.8% |
| 2-34 | Split-level home | 771 | 31.0% |
| 2-03 | One-story home, 1,000–1,800 sq ft | 622 | 29.1% |
| 5-17 | One-story commercial building | 71 | 53.5% |
Among the high-volume single-family classes, success rates clustered in a fairly narrow band — roughly 27% to 35% — around the 31.2% homeowner average. Two things sat outside that group: condo appeals (Class 2-99) were notably lower at 13.6%, and one-story commercial (Class 5-17) reached 53.5%, though on far fewer filings. *A condo appeal often covers a whole building: 66 appeals covered 1,770 units.
What Happened to Assessed Values
The proposed-to-final movement across all appeals was modest but real:
| Average cut, winning homeowner appeals | ~7.9% |
| Typical (median) cut, winning homeowner appeals | $9,481 |
| Average cut in dollars, winning homeowner appeals | $15,197 |
| Homeowner appeals with no change | ~69% |
Assessed value is a key input to your tax bill. A lower final value doesn't translate one-for-one into the same percentage drop in taxes — exemptions and rates also matter — but it can still move an owner into a better position. Even a few percent off the assessed value can mean real dollars over the years it stays in place.
Why 2025 Was a Strong Year — and Why 2026 Still Matters
New Trier is part of the north suburban group, which the Cook County Assessor reassesses once every three years. The last reassessment was 2025; the next is 2028. Reassessment years like 2025 draw the most appeals and the strongest outcomes, because brand-new values create the most opportunities for correction.
But your 2025 value generally carries forward until 2028 unless it's appealed — and Cook County lets you appeal every year. New Trier's 2026 appeal window closed on June 22, 2026. If your reassessed value looks too high, an off-year appeal can correct it before it rides for several more bills.
What These Results Mean for New Trier Owners
Three takeaways stand out. Appeals can work, but outcomes vary — many cases don't change, so preparation matters. Property-class trends are real — similar homes tend to see similar result patterns, so knowing where your property sits helps set expectations. And small percentage changes still matter — a few percent off your assessed value can translate into meaningful dollars over time.
The best next step for most owners is a calm review: check your property facts, confirm your classification, and compare against similar nearby properties. If things look off, review the signs your property is overassessed, or confirm your window on our deadlines page.
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Check My AssessmentNew Trier Township Property Tax Appeal FAQ
What is the New Trier Township appeal success rate?
In 2025, 3,479 of 11,156 homeowner appeals resulted in a change, counting each appeal once — a 31.2% success rate, or roughly three in ten (31.5% across all property types). That's consistent with a reassessment year, which tends to produce higher filing volume and stronger outcomes.
What does "Change" mean on an appeal outcome?
"Change" means the appeal resulted in an adjustment — typically a revised assessed value after review. In this analysis, a "Change" outcome is counted as a successful appeal.
Why do success rates differ by property class in New Trier?
Class codes reflect different property types, and the available evidence varies by category. New Trier's high-volume single-family classes clustered around 27%–35%, condo appeals came in lower near 14%, and one-story commercial reached about 54% on far fewer filings. Knowing your class helps set realistic expectations.
How much did assessed values drop on average?
Among homeowner appeals that won, assessed value fell about 7.9% on average; the typical (median) cut was about $9,480. A lower final value can reduce the taxable value tied to a property, depending on exemptions and the rest of the local tax calculation.
What is the deadline to appeal in New Trier Township?
New Trier's 2026 Cook County Assessor filing deadline was June 22, 2026, and the window has closed. Deadlines differ between the Assessor and the Board of Review and change each year, so confirm the current date before filing.
If my assessment seems too high, what should I check first?
Start with your basic property details (size, features, condition), recent comparable sales, and your property classification code. If those suggest your value is out of line with similar nearby properties, an appeal may be worth pursuing.
Data & Sources
- Cook County Assessor — Appeals dataset (Cook County Data Catalog), New Trier Township (code 23), tax year 2025. A successful appeal is one marked "Change," where the certified assessed value differed from the proposed (mailed) value after review.
- Each appeal is counted once (a condo building's units, decided together, are one appeal); cut averages are taken across winning homeowner appeals.
- Reassessment schedule: New Trier (north suburban group) was reassessed in 2025, with the next reassessment due in 2028. Figures reflect first-level Assessor decisions and do not include separate Board of Review outcomes. All data is public and county-wide; no firm-specific results are stated.
Keep Reading
This article summarizes 2025 Cook County Assessor appeal outcomes for New Trier Township by property class and is general information, not legal or tax advice. Figures are drawn from public Cook County appeal data; individual results depend on the property and the evidence presented. Success rates reflect first-level Assessor decisions only. Filing deadlines are set by the Cook County Assessor and Board of Review — always confirm your window before filing. Representation is subject to a written engagement agreement.
