How it works
How this tool works.
Depreciation lets a landlord recover the cost of a rental building over time. Under the straight-line method, you divide the building’s basis — its value excluding the land, which isn’t depreciable — evenly across the recovery period the tax rules assign to the property type. It’s one of the larger paper deductions a rental produces.
Enter the building basis (and, optionally, the land value so you can see the split), pick the recovery period, and this calculator estimates the annual and monthly straight-line depreciation. It computes straight-line only — it does not calculate recapture, §1250, or bonus depreciation, and it is an estimate, not tax advice.
Enter the building’s basis — its cost excluding the land. If it’s easier, enter total value and land value and the tool shows the depreciable building portion.
Choose the recovery period: 27.5 years for residential rental property, or 39 years for commercial — the two standard periods for the straight-line method.
The tool divides the building basis evenly across the recovery period for the annual figure, then divides by 12 for the monthly figure.
This is a straight-line estimate only. It does not handle the first-year mid-month convention, land allocation rules, recapture on sale, or bonus/§179 — all of which have real tax consequences a CPA should confirm.