Why It Matters
When you sell a rental property, your taxable gain isn't simply sale price minus what you paid. The IRS adjusts your cost basis over time: capital improvements increase it, while MACRS depreciation deductions decrease it every year — even though depreciation costs you nothing in cash. Buy for $300,000, add $40,000 in improvements, take $60,000 in depreciation over seven years, and your adjusted basis is $280,000 — not the $340,000 you spent. Sell for $400,000 and you owe taxes on $120,000 in gain, not $60,000. That gap is depreciation recapture, taxed at 25%.
At a Glance
- Formula: Purchase Price + Closing Costs + Capital Improvements − Accumulated Depreciation
- Why it matters: Determines your taxable gain at sale — lower basis means higher tax bill
- Depreciation effect: Reduces basis by ~3.636% of building value per year (27.5-year residential schedule), whether you claim it or not
- Key distinction: A new roof adds to basis; patching a leak does not
- Primary escape valve: A 1031 exchange defers the gain and carries the adjusted basis to the replacement property
Adjusted Basis = Purchase Price + Closing Costs + Capital Improvements - Accumulated Depreciation
How It Works
Two forces push your basis in opposite directions. Your adjusted basis starts as the purchase price plus acquisition closing costs (title insurance, attorney fees, transfer taxes). Capital improvements — a new HVAC system, a kitchen renovation, an added bedroom — increase it. Depreciation decreases it every year. Only the building value (typically 75–85% of purchase price) gets depreciated over 27.5 years — land is never depreciable.
Depreciation reduces your basis whether you claim it or not. The IRS's "allowed or allowable" rule means if you could have deducted $8,000/year but didn't, your basis still drops. After 10 years, that's $80,000 gone regardless — so always claim your depreciation. Investors who use bonus depreciation to front-load deductions see their basis drop dramatically in year one, amplifying recapture exposure at sale.
At sale, your gain splits into two tax buckets. Taxable gain = sale price − selling costs − adjusted basis. The depreciation recapture portion is taxed at 25% federal; the remaining capital gain at 0%, 15%, or 20% depending on income. Depreciation sits below the NOI line — it doesn't affect your cash-on-cash return during the hold, but it quietly builds a tax liability that materializes at sale. This is why experienced investors view depreciation as a tax timing tool: you save now, you pay later — unless you 1031 exchange indefinitely or hold until death (stepped-up basis eliminates all accumulated depreciation).
Real-World Example
Sofia buys a duplex in Nashville for $300,000. Land is appraised at $50,000, leaving $250,000 in depreciable building value. With $6,000 in closing costs, her starting basis is $306,000.
Over seven years, she adds a $40,000 kitchen renovation and a $12,000 roof replacement ($52,000 total). She claims straight-line depreciation: $250,000 ÷ 27.5 = $9,091/year × 7 = $63,637 accumulated.
Adjusted basis at sale: $306,000 + $52,000 − $63,637 = $294,363. She sells for $420,000 with $25,200 in selling costs (6%). Taxable gain: $420,000 − $25,200 − $294,363 = $100,437.
Sofia's total cash in was $358,000; she netted $394,800 — actual profit of $36,800. But her taxable gain is $100,437 because depreciation reduced her basis by $63,637. Recapture at 25%: $15,909. Capital gains at 15%: $5,520. Total tax: ~$21,429 on $36,800 cash profit — a 58% effective rate, unless she 1031 exchanges.
Pros & Cons
- Tracks your true tax position throughout the hold — no surprises at sale if you maintain a running calculation
- Every documented capital improvement reduces your taxable gain at sale — dollar for dollar
- Makes 1031 exchange decisions data-driven: you know exactly how much tax you're deferring
- Stepped-up basis at death eliminates all accumulated depreciation for heirs — a powerful estate planning tool
- The "allowed or allowable" rule means basis erodes whether you claim depreciation or not — there's no way to avoid it on rental property
- Capital improvement vs. repair classification is a gray area — a new water heater might be either, depending on circumstances
- Basis tracking over decades requires meticulous records: every closing statement, improvement receipt, and depreciation schedule
- Depreciation recapture at 25% can create a tax bill exceeding your actual cash profit on properties held 10+ years with modest appreciation
Watch Out
Skipping depreciation hurts you twice. The IRS's "allowed or allowable" rule reduces your basis whether you claimed the deduction or not. Skip it for 10 years and you lose the annual tax savings AND still face full recapture at sale. If your CPA hasn't been filing depreciation, file Form 3115 to claim the catch-up — no amended returns needed.
Property taxes and mortgage interest do NOT adjust your basis. These are annual deductions, not capital expenditures. Only permanent improvements to the physical property add to basis. Operating expenses — property taxes, insurance, management fees, repairs — are deducted annually and have zero impact on adjusted basis.
Bonus depreciation creates a recapture time bomb. Claim $80,000 via cost segregation in year one and your basis drops $80,000 immediately. Sell three years later and you face 25% recapture — $20,000 in federal tax from depreciation alone. Accelerated strategies only make sense if you plan to hold long-term or 1031 exchange out.
Ask an Investor
The Takeaway
Your adjusted basis is the single number that determines your tax bill at sale. It starts at your purchase price, grows with every capital improvement, and shrinks with every year of depreciation. Track it from day one, save every improvement receipt, claim depreciation every year, and know your number before deciding whether to sell or 1031 exchange. The investors who get burned are the ones who don't check their adjusted basis until they're at the closing table.