Real Estate Tax Calc
Boot, defined
Boot is any value you receive in an exchange that isn't like-kind property — usually cash left over or a reduction in your mortgage debt. Boot is taxable up to the amount of your gain, even inside an otherwise valid 1031.
Cash boot vs. mortgage boot
Cash boot: proceeds you pocket instead of reinvesting. Mortgage boot: your new loan is smaller than the old one, so you're treated as having received the difference.
Avoiding accidental boot
Reinvest all the equity and replace debt with equal or greater debt (or add cash). Buying a cheaper property, or borrowing less, quietly creates boot.
The rule that ties it together: recognized gain
Here's the principle that governs boot. In a 1031 exchange your realized gain (economic profit) may be large, but you only recognize (pay tax on) the lesser of the boot received or the realized gain. So boot doesn't manufacture tax out of thin air — it caps how much of your existing gain gets pulled forward. If you have $200,000 of realized gain and receive $30,000 of boot, you recognize $30,000; if you receive $250,000 of boot, you recognize only the $200,000 you actually gained.
That's why a well-structured exchange with zero boot defers 100% of the gain, and why even a partial exchange with some boot still defers the rest.
The two-part boot test: value and equity, plus debt
To end up boot-free, the replacement property generally has to clear two hurdles. Trade equal or up in value: the replacement's price should equal or exceed the relinquished property's net sale price. Reinvest all the net equity: every dollar the qualified intermediary holds must go into the purchase — cash you keep is cash boot. Replace the debt: the new mortgage should equal or exceed the old one, or you make up any shortfall with out-of-pocket cash.
Miss any of these and boot appears. Buy cheaper, and you have leftover cash (cash boot). Borrow less, and the debt reduction is mortgage boot. Pocket some proceeds "just in case," and that's cash boot too.
How netting works — and the asymmetry that trips people up
The IRS lets you net the debt on both sides. If your old loan was $300,000 and your new loan is $350,000, you've taken on more debt, so there's no mortgage boot. If the new loan is only $250,000, you have $50,000 of mortgage boot — unless you add $50,000 of your own cash to the purchase, which offsets it.
The asymmetry: adding cash offsets mortgage boot, but taking on extra debt does NOT offset cash boot. If you pull $40,000 of proceeds out of the exchange, taking on a bigger mortgage won't cancel that cash boot — the $40,000 you received in cash is taxable up to your gain no matter how much you borrow. Cash in your pocket is always boot; only cash you put in shelters debt relief.
A worked example with boot
You sell a rental for $500,000 net, with a $200,000 mortgage paid off at closing, leaving $300,000 of equity held by your QI. Your adjusted basis was $250,000, so your realized gain is $250,000. You buy a replacement for $460,000 with a new $180,000 loan, putting $280,000 of the equity in.
Result: you have $20,000 of cash boot (the $20,000 of equity the QI returns to you because the new deal needed less) and $20,000 of mortgage boot (debt dropped from $200,000 to $180,000). The mortgage boot could have been offset by adding $20,000 cash, but you didn't — and the cash boot can't be offset at all. You'd recognize roughly $40,000 of gain (limited to your $250,000 realized gain), taxed as a mix of unrecaptured Section 1250 recapture and capital gain, while the remaining ~$210,000 stays deferred.
Hidden sources of boot at closing
Boot often sneaks in through the settlement statement, not a deliberate decision to keep cash. Watch for: prorated rents and security deposits credited to you (better handled outside the exchange), non-transactional closing costs paid from exchange funds (loan fees, prepaid interest, and property taxes can create boot; brokerage commissions and QI fees generally don't), excess financing where you borrow more than the purchase price and take the difference, and personal property included with the real estate. Since the 2017 Tax Cuts and Jobs Act, only real property qualifies for 1031, so any personal property (furniture in a furnished rental, for instance) received is boot.
Have your QI and closing agent structure these items deliberately, and bring separate personal funds to cover non-exchange expenses rather than dipping into proceeds.
How boot affects your replacement property's basis
Boot doesn't just trigger tax — it changes your carryover basis. Your replacement property's basis is generally your old basis, minus any boot received, plus any gain you recognized and any additional cash you invested. Recognizing gain on boot "uses up" some deferral now but correspondingly increases your basis going forward, which slightly raises future depreciation and reduces the gain deferred into the next sale. It's a real tradeoff, not a free lunch, so model the basis effect, not just the current-year tax.
What kind of gain does boot trigger?
When boot forces you to recognize gain, that gain isn't automatically capital gain — it takes on the character of the underlying gain. Under the ordering rules, recognized gain is generally treated first as depreciation recapture. So if your relinquished property had cost-segregated Section 1245 components, boot can trigger ordinary-rate recapture before any capital gain. On a straight residential rental, the recognized gain is usually unrecaptured Section 1250 gain (up to 25%) and then long-term capital gain (0/15/20%). Knowing the character matters because it determines the rate, and it's why a small amount of boot on a heavily cost-segregated property can be taxed more harshly than you'd expect.
How boot is reported on Form 8824
Every 1031 exchange is reported on Form 8824 (Like-Kind Exchanges). It's where you disclose the properties, the dates that prove you met the 45-day and 180-day deadlines, the fair market values, and — critically — the boot received and the resulting recognized gain. The form walks through the netting of cash and liabilities and computes your recognized gain and your new basis. Any recognized gain then flows to Form 4797 and/or Schedule D depending on its character. File Form 8824 for the tax year the relinquished property was transferred, even if the replacement closes in the following year.
Debt netting in depth: a common misconception
Investors often panic about mortgage boot when they shouldn't. Remember the two offsets that do work: taking on more or equal debt eliminates mortgage boot, and adding cash to the purchase eliminates mortgage boot dollar-for-dollar. What creates trouble is decreasing debt without replacing it. Example: you had a $400,000 loan and take a $320,000 loan on the replacement, but you also bring $80,000 of fresh cash to closing — no mortgage boot, because the added cash offsets the $80,000 of debt relief. The regulations net the liabilities and cash together; only a net reduction in your investment produces taxable boot.
Practical checklist to finish boot-free
Before closing the replacement, confirm each of these with your QI: (1) the replacement's purchase price is equal to or greater than the relinquished property's net sale price; (2) all exchange proceeds held by the QI are applied to the purchase, with none returned to you; (3) the new debt is equal to or greater than the retired debt, or any shortfall is covered by your own cash added to the deal; (4) no personal property or non-like-kind assets are being received as part of the trade; and (5) prorations, deposits, and non-transactional costs are handled outside the exchange funds. Clearing all five is how you defer 100% of the gain — miss one and you've created boot, often without meaning to.
When accepting boot is actually the right call
Boot isn't always a mistake. Sometimes you deliberately trade down — you want to pull equity out for another purpose, retire, or reduce leverage — and accept the tax on the boot as the price of freeing up cash. That's a legitimate partial exchange: you defer the reinvested portion and pay tax only on what you take out. The key is doing it on purpose and knowing the number in advance, rather than discovering unexpected boot on your tax return. If you need liquidity, a planned partial exchange is far better than an all-or-nothing sale, because you still shelter most of the gain.
Run the boot number before you close, not after
The single best habit is to compute your expected boot before signing the replacement purchase — not to discover it on next year's tax return. Ask your qualified intermediary for a preliminary settlement analysis that lays out the relinquished net sale price, the replacement price, the old and new debt, and the equity being reinvested. If any of the three tests (value, equity, debt) comes up short, you'll see the boot in advance and can decide whether to add cash, borrow more, or accept the tax deliberately. A ten-minute review with your QI and CPA before closing routinely saves investors an unexpected five-figure tax bill they never intended to trigger.
Frequently asked questions
Is boot taxable?
Yes, boot is taxable up to the amount of your gain, even within a valid 1031 exchange.
How do I avoid boot?
Reinvest all proceeds and match or exceed your old debt level on the replacement property.
Does taking on a bigger mortgage cancel out cash I pocket?
No. Extra debt can't offset cash boot. Cash you receive is taxable up to your gain regardless of how much you borrow. Only cash you add to the deal offsets mortgage (debt-relief) boot.
How much tax do I pay on boot?
You recognize the lesser of the boot received or your total realized gain, taxed as a blend of depreciation recapture (up to 25%) and capital gain (0/15/20%), plus any NIIT and state tax.
Do closing costs create boot?
Some can. Transactional costs like brokerage commissions and the QI fee generally don't, but paying items like loan fees, prepaid interest, or prorated property taxes out of exchange funds can. Cover non-exchange expenses with separate cash.
Sources
Educational information and estimates only. Not tax advice. Tax rules change and vary by situation; consult a qualified tax professional before acting.