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Straight-line depreciation calculator
Estimate the annual and monthly straight-line depreciation on a rental building over its recovery period. Straight-line only — an estimate, not tax advice.
Estimate only — not tax advice.
The short answer
Last updated: July 2026
Straight-line depreciation spreads a rental building’s basis (its cost excluding non-depreciable land) evenly across its recovery period — 27.5 years for residential rental property or 39 years for commercial. Annual depreciation is the building basis ÷ the recovery period. This is a straight-line estimate only; it excludes recapture, first-year conventions, and land rules — not tax advice.
Primary references on this page:
After the estimate:
Tax records and AptoriaStraight-line depreciation calculator
Estimate straight-line depreciation.
Divide the building's basis — the value excluding non-depreciable land — evenly across the recovery period for an annual and monthly straight-line estimate.
Building basis (excludes land)
$
The depreciable cost of the structure only — land isn't depreciable.
Land value (optional)
$
For reference only — land is excluded from depreciation. Allocating price between land and building has real tax consequences; confirm the split with a CPA.
Recovery period
27.5 yrs — residential
39 yrs — commercial
Input-driven result
Your inputs
Formula
Result below
Annual depreciation
$10,909
$300,000 building basis ÷ 27.5 years.
Monthly depreciation
$909
Annual depreciation ÷ 12.
Basis allocation used for this estimate
Depreciable building basis
$300,000
Land excluded from depreciation
$0
First full-year deduction
$10,909
Estimate based on your inputs. Not a promise of results.
Estimate only — not tax advice. Straight-line depreciation ONLY. It does not compute the first-year convention, land-allocation rules, bonus/§179, or depreciation recapture (§1250/§1245) on a sale — all of which have real tax consequences. Confirm with a CPA. Aptoria is not a tax advisor.
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.
Make the result useful
Separate a planning schedule from a tax return
Straight-line depreciation spreads an allocated basis evenly over a recovery period. The hard part is not the division; it is determining eligible basis, land allocation, placed-in-service date, and the rules that apply to the property.
Use this tool to understand the math, then rely on tax records and a professional for the actual return.
Can I depreciate land?
Land treatment differs; confirm allocation and tax treatment with a qualified professional.
Questions landlords ask
Questions about this tool and its limits.
Estimate only — not tax advice. This computes straight-line depreciation only. Depreciation, recapture, and land allocation have real tax consequences; confirm with a CPA. Aptoria is not a tax advisor.
Built by a landlord who's done every one of these jobs by hand.
Aptoria was built by an owner-operator managing a Brooklyn portfolio — the 11pm calls, the awkward rent texts, the April receipt-pile — not by a software team guessing at the problem.
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