Most of what gets written about cost segregation results is a marketing claim: "reclassify 20 to 40 percent of your property!" The range is technically honest and practically useless, because it is almost never backed by data anyone can check.
So we measured ours. This report is built from every cost segregation study RentalWriteOff has delivered on residential rental properties, from single-family rentals and condos to Airbnbs and small multifamily, with purchase prices from under $100,000 to several million dollars. Not a sample, not our best results. All of them.
Methodology, up front
- We parsed the asset allocation schedule from every delivered study report, complete through July 2026, with no study excluded.
- Reclassified share = (5-year + 7-year + 15-year allocations) ÷ total depreciable basis. Land is excluded from the basis, so these percentages are of the amount that can actually depreciate.
- We report medians and quartiles, not averages, so one large property cannot skew the numbers.
- Groups with too few studies to be statistically meaningful are not published.
- Every underlying allocation sums to its report's total.
The headline numbers
| Group | Median reclassified | Middle 50% of studies | Median reclassified dollars |
|---|---|---|---|
| All completed studies | 26.1% | 20.4% to 33.7% | $100,000 |
| Long-term rentals (27.5-year) | 26.0% | 20.8% to 31.2% | $61,000 |
| Short-term rentals (39-year) | 26.8% | 20.1% to 37.8% | $113,000 |
The median study moved 26.1% of the property's depreciable basis out of the slow 27.5- or 39-year schedule and into 5-, 7-, and 15-year property. Roughly 1 in 3 studies (31%) reclassified more than 30%.
Within the reclassified share, the median study allocated 16.6% of basis to 5-year property (appliances, carpet, cabinetry, dedicated electrical) and 7.8% to 15-year property (driveways, fencing, landscaping, other site improvements).
The finding that surprised us: smaller properties reclassify more
| Purchase price | Median reclassified | Middle 50% of studies | Median reclassified dollars |
|---|---|---|---|
| Under $350,000 | 27.6% | 22.4% to 38.1% | $46,000 |
| $350,000 to $700,000 | 27.2% | 24.1% to 29.5% | $112,000 |
| $700,000 and up | 20.6% | 14.3% to 24.5% | $156,000 |
The conventional wisdom says cost segregation is a big-building strategy. Our data says the opposite, at least in percentage terms: properties under $350,000 reclassified a larger share of their basis (median 27.6%) than properties over $700,000 (median 20.6%).
The likely reason: in a modest rental, the short-life components (appliances, flooring, cabinets, the driveway, the fence) are a big fraction of what you bought. In an expensive property, more of the price sits in the structure itself and in location value. The expensive property still reclassifies more dollars ($156,000 median vs $46,000), but the percentage story flips.
For the owner of an ordinary rental, that is the whole argument: the properties that were historically priced out of cost segregation (studies from traditional firms run $5,000 to $15,000) are the ones where it does proportionally the most work.
Short-term rentals: same median, bigger upside
Long-term and short-term rentals had nearly identical medians (26.0% vs 26.8%). The difference is in the top quartile: the top 25% of short-term rental studies reclassified more than 37.8% of basis, versus 31.2% for long-term rentals. Furnishings, higher-turnover finishes, and amenity-heavy properties push STRs higher when the ingredients are there.
What the median result is worth in taxes
The median study reclassified about $100,000. What that is worth depends on your bonus depreciation rate (100% for property acquired after January 19, 2025, lower for 2023 and 2024 placements), your tax bracket, and the passive loss rules for your situation. At 100% bonus and a 37% marginal rate, a $100,000 reclassification is roughly a $37,000 first-year tax reduction. Every study RentalWriteOff delivers costs a flat $799.
Honest limitations
- This is one provider's data, residential focus, weighted toward single-family rentals, condos, and short-term rentals.
- Medians describe typical results, not your property. The middle 50% spans roughly 20% to 34%, and individual studies ranged from under 10% to over 45%.
- A reclassified percentage is not a tax refund. What you can use in a given year depends on bonus depreciation rates and passive loss rules. This report is information, not tax advice.
Check your own property against these benchmarks
The free instant estimate pulls your county's records and projects your property's numbers in about a minute. The same estimates and this benchmark data are also available inside ChatGPT and Claude through our connector. If the estimate looks like the tables above, the full engineering-based study is $799 flat, delivered in 2 business days, audit support included.
We will update these benchmarks as the completed-study count grows. Journalists and researchers: you are welcome to cite this report with attribution to RentalWriteOff; write to support@rentalwriteoff.com for questions about the methodology.