Enter the property's basics below. We reclassify the depreciable basis into 5-year personal property, 15-year land improvements, and 27.5- or 39-year real property using IRS-recognized industry allocation ranges, apply the correct bonus depreciation under the One Big Beautiful Bill Act (OBBBA), and show your projected first-year deduction, tax savings, and 10-year cumulative benefit as a low-to-high range calibrated to engineering-study variance.
Fill in the property and tax details on the left, then click Calculate Estimate.
| Asset Class | Recovery | Method | Allocated Basis (range) | Bonus-Eligible (range) |
|---|---|---|---|---|
| Total Depreciable Basis | — | — | ||
The shaded cyan band shows the low-to-high range of cumulative deductions with cost segregation, vs. the dotted line for standard straight-line depreciation.
This estimate shows a defensible range using industry-standard allocations. A full TDA cost segregation study uses RSMeans construction data and construction document review to nail down the actual number — typically at the higher end of this range or above.
Why a range, not a single number. Cost segregation results vary with the specific building, its components, and engineering judgment. We display estimates as a range — ±20% for both residential and commercial property — and this range is subject to change. The midpoint is shown beneath each range as a reference point. A real engineering study typically lands at or above the high end of this range.
Asset reclassification. Cost segregation studies break the building cost into MACRS asset classes per IRS Rev. Proc. 87-56 and Pub. 946. Personal property (carpet, cabinetry, appliances, decorative lighting, FF&E) is depreciated over 5 years using the 200% declining-balance method. Land improvements (paving, fencing, site lighting, landscaping) are depreciated over 15 years using 150% declining balance. The remaining structural building cost stays on the standard 27.5-year (residential rental) or 39-year (commercial) straight-line schedule with the mid-month convention.
Bonus depreciation under OBBBA. The One Big Beautiful Bill Act (signed July 4, 2025) permanently restored 100% first-year bonus depreciation under §168(k) for qualified property acquired and placed in service after January 19, 2025. Property placed in service before that date follows the prior TCJA phase-down: 100% (2017–2022), 80% (2023), 60% (2024), 40% (Jan 1–Jan 19, 2025). Bonus applies to property with a recovery period of 20 years or less — here, the 5-year and 15-year reclassified portions.