Ten fields, one pass: sale price, basis, the mortgage numbers on both sides, and this tool separates what the IRS lets you carry forward from what it collects this year.
Figures assume 2026 federal rates and no state tax layered on top.
Sell investment real estate outright and two tax bills land at once: capital gains on the profit, and a separate recapture bill on every dollar of depreciation you deducted along the way. Swap into a new like-kind property under Section 1031 instead, and both bills wait. Nothing here changes what you'd file; the calculator above just prices the trade before you make it.
Gain realized comes from the sale price minus selling costs and adjusted basis. From there, the tool checks how much value left the deal as boot, meaning cash you pocketed or mortgage debt you shed without replacing it. Boot gets taxed now, up to the size of the gain; the rest defers. What's left over splits again, since depreciation recapture and ordinary capital gain carry different rates.
| Line item | Rate |
|---|---|
| Depreciation recapture (Section 1250, real property) | 25% |
| Long-term capital gain + 3.8% NIIT, combined | 23.8% |
Sell for $500,000 against a $300,000 basis with $30,000 in closing costs and the gain realized is $170,000. Buy a replacement worth at least that much, carrying at least as much debt, and boot lands at zero: the full $170,000 defers, and the calculator shows your entire net sale proceeds available to reinvest. Buy something smaller, or walk away with cash, and that gap becomes boot, taxed at the blended recapture and capital gains rates shown above.
For deadline math, the timeline calculator turns your closing date into hard dates. For the without-exchange comparison, try the capital gains tax calculator.
Model boot on its own, check the deadline math, or price out the sale without an exchange.
Cash you keep instead of reinvesting, plus any net drop in mortgage debt between the sale and the purchase. The calculator adds both together and taxes that total up to the size of your gain.
Yes, to the extent the gain itself defers. Only the recognized (boot) portion of your recapture becomes taxable now, at the 25% rate; the rest carries into the replacement property's basis.
Because the IRS taxes the two pieces differently. Depreciation you already claimed is recaptured at 25% under Section 1250, while the leftover gain is taxed at the long-term capital gains rate plus NIIT, currently up to 23.8% combined.
The shortfall shows up as boot in the results panel and gets taxed up to the amount of your total gain. Buying equal or greater value, with equal or greater debt, is what drives boot to zero.
Treat the output as a planning estimate, not a closing statement. Your qualified intermediary and tax preparer will apply your actual basis, state rules, and filing status before you sign anything.