§ 1031 EXCHANGE CALCULATOR

Use this calculator to estimate the federal income tax consequences of a like-kind exchange of investment or business real property under Internal Revenue Code § 1031. Enter the figures from the relinquished property, the replacement property, and any cash boot or net mortgage relief. The calculator computes realized gain, recognized gain (the lesser of realized gain or boot), deferred gain, and the substituted basis in the replacement property.

RELINQUISHED PROPERTY
Original cost less depreciation, plus capital improvements.
Gross sale price of the relinquished property.
Commissions, closing costs, transfer taxes paid by seller.
Debt on the relinquished property paid off from the proceeds.
REPLACEMENT PROPERTY
Total purchase price of the replacement property.
New or assumed debt on the replacement property.
Cash received that was not reinvested in the replacement property.

Calculation Results

Amount realized (sale price less selling expenses)
Realized gain
Net mortgage relief (treated as boot if positive)
Total boot (cash boot + net mortgage relief)
Recognized gain (taxable)
Deferred gain
Basis in replacement property
HOW THIS CALCULATION WORKS

The calculator applies the standard like-kind exchange computation under § 1001 (realized gain), § 1031 (deferral), § 1031(b) (boot recognition), and § 1031(d) (substituted basis):

  • Amount realized = Sale price − Selling expenses
  • Realized gain = Amount realized − Adjusted basis
  • Net mortgage relief = Mortgage paid off − Mortgage on replacement (if positive; if negative, treated as zero for boot purposes)
  • Total boot = Cash boot received + Net mortgage relief
  • Recognized gain = Lesser of realized gain or total boot
  • Deferred gain = Realized gain − Recognized gain
  • Basis in replacement = Replacement property cost − Deferred gain

The calculator assumes the exchange satisfies the like-kind, qualified intermediary, identification, and exchange-period requirements of § 1031 and Treasury Regulations §§ 1.1031(a)-1 through 1.1031(k)-1. Failure to satisfy any of those requirements can disqualify the exchange and cause full recognition of the realized gain.

Important. This calculator does not address state income tax, depreciation recapture under § 1245 or § 1250 (which is recognized to the extent of boot regardless of deferral), the use of qualified intermediaries, the 45-day identification or 180-day exchange-period rules, partial-interest exchanges, related-party rules under § 1031(f), or partnership-level issues. The calculator assumes the relinquished and replacement properties are real property held for investment or productive use in a trade or business and that the exchange satisfies the technical requirements for like-kind treatment. Specific structuring, timing, and documentation issues should be reviewed with qualified counsel before any exchange is initiated.

Need Help With Your Specific Matter?

The calculations above are based on simplified assumptions. To discuss your specific situation with the firm, contact us directly.

Contact The Firm
© Donovan Legal PLLC. 2026. | DISCLAIMER