An investor sells a rental property for $500,000, rolls the proceeds into a $460,000 replacement property, and pockets $40,000 thinking the whole transaction is tax-free. Three months later, the IRS sends a bill for $12,800. That $40,000 they kept is called 1031 exchange boot — and it gets taxed just like a regular sale. Understanding exactly how boot works before you close can save you thousands.
What is 1031 exchange boot? Boot is any value you receive in a 1031 exchange that is not like-kind property — cash taken out, net mortgage relief, or non-qualifying property. The IRS taxes boot in the year of the exchange. It does not get the tax-deferral benefit that the rest of the transaction receives. Boot is taxed as capital gain (15% or 20%), may carry depreciation recapture at 25%, and could trigger the 3.8% Net Investment Income Tax. Even if you reinvest every dollar of cash, a drop in mortgage balance on the replacement property creates mortgage boot — a trap many investors miss until after closing.
What Is Boot in a 1031 Exchange?
A 1031 exchange lets you defer capital gains tax when you sell an investment property and reinvest the proceeds into a like-kind replacement. The tax deferral is not unlimited, though. The IRS only defers tax on the portion of the transaction that qualifies — the rest gets taxed immediately.
That taxable remainder is called boot. The word dates to 19th-century trade law, where “to boot” meant something thrown in to balance an uneven exchange. In modern real estate, boot means any non-like-kind value you walk away with after the exchange closes.
The governing rule is IRS Section 1031. To fully defer tax, you must:
- Reinvest all net sale proceeds into the replacement property
- Buy a replacement property of equal or greater value than the relinquished property
- Take on equal or greater debt on the replacement (or add cash to make up any difference)
Fail any of those three conditions, and the shortfall becomes 1031 exchange boot — taxable in the year of the exchange, not deferred. You report it on Form 8824 along with your regular tax return.
A common misconception: boot does not void the entire exchange. Only the boot amount is taxed; the rest of your gain stays deferred. So even an imperfect exchange is usually better than a straight sale.
Types of Boot
Boot comes in three forms. Each is taxed the same way, but each arises from a different transaction structure. Knowing the difference keeps you from creating boot accidentally.
Cash Boot
Cash boot is the most straightforward type. It occurs when you receive cash — or any cash equivalent — from the exchange proceeds rather than rolling all of it into the replacement property.
Example: You sell a duplex for $350,000 with a remaining mortgage of $100,000. Your net equity is $250,000. You buy a replacement property for $220,000 (also all-cash). Your Qualified Intermediary pays you the leftover $30,000. That $30,000 is cash boot, and it is taxable in the year of the exchange.
Cash boot also includes closing costs paid with exchange funds if those costs are personal expenses (e.g., prorated rent credits to the buyer, points you pay on a new loan, or earnest money you recapture). Legitimate selling costs like commissions and title fees, on the other hand, reduce your net proceeds and do not create boot.
Mortgage Boot (Debt Relief Boot)
Mortgage boot — sometimes called debt relief boot — is the most common surprise in a 1031 exchange. It arises when the mortgage on your replacement property is lower than the mortgage on the property you sold.
Example: You sell a property with a $300,000 mortgage. You buy a replacement with only a $220,000 mortgage. Even if you rolled every dollar of cash equity into the new property, the $80,000 drop in debt is treated as boot. The IRS views that debt relief as if you pocketed $80,000 in cash.
The fix is simple in theory: either buy a replacement with equal or higher debt, or make up the difference by adding cash from outside the exchange. We cover this in detail in the Mortgage Boot section below.
Property Boot (Non-Like-Kind Property)
Property boot is what you receive when part of the exchange includes assets that do not qualify as like-kind real property under Section 1031. Personal property — furniture, appliances, equipment — used to qualify for like-kind exchanges, but the Tax Cuts and Jobs Act of 2017 eliminated that. Since January 1, 2018, only real property qualifies.
Example: You sell a furnished vacation rental for $400,000. The buyer pays $385,000 for the real property and $15,000 for the furniture package. If you receive the furniture proceeds rather than redirecting them to a like-kind replacement, that $15,000 is property boot.
The same logic applies to items like a boat slip sold alongside a marina, or mineral rights bundled with a ranch sale — you need to separate qualifying from non-qualifying assets and handle them distinctly.
How Boot Is Taxed
Boot does not get a special low rate. It is taxed using the same layers that would apply if you had sold the property outright — with one advantage: you only owe tax on the boot amount, not on the full gain.
Here are the tax layers that apply to 1031 exchange boot:
| Tax Layer | Rate | Applies To |
|---|---|---|
| Depreciation Recapture | 25% | Gain attributable to prior depreciation deductions (Section 1250) |
| Long-Term Capital Gains | 15% or 20% | Remaining gain above the depreciation recapture amount |
| Net Investment Income Tax (NIIT) | 3.8% | High-income investors (MAGI over $200K single / $250K married) |
| State Income Tax | 0%–13.3% | Varies by state; some states do not recognize 1031 exchanges |
The IRS allocates boot to the most heavily taxed gain first. Depreciation recapture comes out before capital gains — meaning your first dollars of boot are taxed at 25%, then additional boot at 15% or 20%. This ordering makes even modest boot expensive.
For a deeper look at how capital gains rates interact with your income bracket, the capital gains tax calculator at arvcalc.com lets you model different scenarios before you commit to a deal structure. You can also read the full breakdown in our capital gains tax guide.
Worked Example: $80K Boot on a $500K Sale
Let’s walk through a realistic scenario so you can see exactly what 1031 exchange boot costs in dollars.
The Setup
- Sale price of relinquished property: $500,000
- Original purchase price (adjusted basis): $220,000
- Total depreciation taken over 12 years: $60,000
- Adjusted basis at sale: $220,000 − $60,000 = $160,000
- Total realized gain: $500,000 − $160,000 = $340,000
- Existing mortgage paid off at closing: $150,000
- Net equity (cash available to reinvest): $500,000 − $150,000 − $10,000 selling costs = $340,000
- Replacement property purchase price: $420,000
- New mortgage on replacement: $150,000
- Cash from equity used to close: $270,000
- Cash not reinvested (cash boot): $70,000
- Mortgage relief boot: $150,000 old debt − $150,000 new debt = $0
- Total boot: $70,000
Wait — the headline said $80K. Let’s adjust: the investor also received a $10,000 security deposit refund from the old property handled outside the QI. Add that in and total boot is $80,000.
Allocating the $80,000 Boot
Remember, boot gets allocated to the highest-taxed gain first.
- Depreciation recapture portion: The investor claimed $60,000 in depreciation. The first $60,000 of boot is taxed at 25% (Section 1250 unrecaptured gain).
- Capital gain portion: The remaining $20,000 of boot ($80K − $60K) is long-term capital gain taxed at 20% (assume this investor has $600K household income, placing them in the 20% LTCG bracket).
- NIIT: At $600K income, the full $80,000 of boot is subject to the 3.8% Net Investment Income Tax.
Tax Calculation
| Tax Layer | Amount Subject | Rate | Tax Owed |
|---|---|---|---|
| Depreciation Recapture | $60,000 | 25% | $15,000 |
| Long-Term Capital Gain | $20,000 | 20% | $4,000 |
| NIIT | $80,000 | 3.8% | $3,040 |
| State Tax (CA example) | $80,000 | 9.3% | $7,440 |
| Total Tax on $80,000 Boot | ~36.8% | $29,480 |
The investor keeps $80,000 in cash but owes roughly $29,480 in combined federal and state taxes — an effective rate near 37% on the boot. That is nearly the same rate as if they had sold outright and made no exchange at all. The $260,000 in deferred gain (the non-boot portion) remains fully deferred.
Plug your own numbers into the 1031 exchange calculator to see your exact boot exposure before you sign a purchase agreement.
Calculate Your 1031 Boot Before You Close
Enter your sale price, basis, mortgage balances, and replacement property details. Get your exact boot amount and estimated tax bill in seconds.
How to Avoid Boot
Boot is optional in most cases. With careful planning before you close, you can structure the exchange to defer 100% of your gain. Here are five strategies that work.
1. Buy a Replacement Property of Equal or Greater Value
This is the most direct solution. If your relinquished property sold for $500,000, your replacement needs to have a purchase price of at least $500,000. A common mistake is comparing sale price to equity — you must match the full value of what you sold, not just the net proceeds you received.
2. Roll All Proceeds Into the Replacement
Every dollar your Qualified Intermediary holds after the relinquished property closes must go toward the replacement. Do not instruct the QI to release funds to you, your attorney, or anyone else before the replacement property closes — that cash immediately becomes taxable boot.
3. Add Outside Cash to Cover Any Gap
If the replacement property you want costs less than your relinquished property (or you are trading down in debt), you can add cash from sources outside the exchange to make up the difference. This does not reduce your boot — it offsets it. Dollar for dollar, every dollar of outside cash you bring to closing reduces your boot by one dollar.
4. Refinance the Replacement Property After Closing
If you already closed the exchange and are now sitting on mortgage boot, a cash-out refinance on the replacement property can pull equity back out as debt — not as boot. This does not retroactively fix the boot on your return, but it is a legitimate strategy when you are planning a multi-leg exchange and need to free up capital.
Some investors also use a refinance on the relinquished property before the exchange to pull out cash tax-free. The IRS has challenged this in cases where the refinance was too close to the sale date (the “step transaction” doctrine). Give yourself at least six months between a pre-exchange refinance and the property sale.
5. Avoid Receiving Non-Like-Kind Property
When negotiating the sale of your relinquished property, be careful what you accept as part of the price. Personal property, a seller credit for repairs paid in cash at closing, or a partial carryback note where you become the lender — all of these can create property boot. Structure your sale so that you receive only real property or cash that flows directly to the QI.
For a fuller look at tax avoidance strategies on investment property, see our guide on how to avoid capital gains tax on investment property. And if you need to assess whether a replacement property generates enough income to justify the exchange, run the numbers in the property cash flow calculator and the cap rate calculator.
Mortgage Boot: The Trap Most Investors Miss
Of all the ways 1031 exchange boot gets created, mortgage boot catches experienced investors off guard more than any other. You can execute a textbook exchange — use a QI, meet the 45-day and 180-day deadlines, reinvest every dollar of cash — and still owe tax because your new loan is smaller than your old one.
Here is how it works.
A Step-by-Step Example
Sarah owns a small apartment building free of debt (no mortgage). She sells it for $600,000. She wants to buy a single-family rental for $650,000, taking out a $200,000 mortgage to help fund the purchase.
Wait — she is going from $0 debt to $200,000 debt. Does she have mortgage boot? No. Her net debt increased, so there is no boot on the mortgage side. She brings the remaining $450,000 in cash from the exchange, no boot is triggered, and the exchange is clean.
Now flip the scenario. David sells a commercial building for $800,000. He has a $300,000 mortgage on the property, which gets paid off at closing. His net equity: $500,000. He buys a replacement property for $820,000 — higher value, so he thinks he is safe. He takes out a $150,000 mortgage on the replacement and puts in $500,000 of equity from the exchange.
The problem: David went from $300,000 in mortgage debt down to $150,000. That $150,000 reduction in debt is treated as if he received $150,000 in cash. Even though every dollar of his equity went into the replacement — and even though the replacement cost more than the relinquished property — David has $150,000 in mortgage boot.
| Relinquished Property | Replacement Property | |
|---|---|---|
| Property Value | $800,000 | $820,000 |
| Mortgage | $300,000 | $150,000 |
| Net Debt Change | −$150,000 (boot!) | |
| Mortgage Boot Created | $150,000 | |
The fix: David should have taken out a $300,000 or larger mortgage on the replacement, bringing his debt level up to match what he had on the relinquished property. Alternatively, if he wanted less debt, he could add $150,000 of outside cash to offset the mortgage boot dollar for dollar.
Mortgage boot is why it pays to run your exchange through a calculator before you structure the financing. The 1031 exchange calculator handles mortgage boot automatically — input both mortgage balances and it tells you whether you have an issue before it becomes a tax bill. You can also read our complete 1031 exchange guide and the 1031 exchange timeline guide for more on exchange mechanics.
Common Mistakes That Create Boot
Most boot is created by accident. These four mistakes account for the majority of unintentional taxable events in 1031 exchanges.
Mistake 1: Taking Excess Closing Costs From Exchange Funds
Some closing costs are eligible to be paid from exchange proceeds — commissions, title insurance, and transfer taxes, for example. Others are not: loan origination fees, prepaid hazard insurance, property tax proration credits, and homeowner association dues paid at closing. If exchange funds cover a non-qualifying cost, that amount becomes boot. Your QI should be able to provide a list of approved and non-approved costs, but verify with your tax advisor before closing.
Mistake 2: Mismatching the Property Identification
Within 45 days of selling your relinquished property, you must formally identify up to three potential replacement properties (or use one of the alternative identification rules). If you fail to identify a property correctly — wrong address, wrong legal description, or an identification that gets disqualified — your exchange could fail entirely, and all proceeds become boot. Double-check every identification letter before the 45-day clock expires. See our 1031 exchange timeline guide for the exact deadline rules.
Mistake 3: Using a Related Party Without Proper Structuring
Buying a replacement property from a family member or a company you control is not automatically disqualifying — but the IRS scrutinizes related-party exchanges heavily under Section 1031(f). If the related party disposes of the replacement within two years, the original exchange can be unwound and all deferred gain becomes taxable. This creates a hidden boot risk that surfaces two years after the exchange closes, not at closing.
Mistake 4: Receiving Boot Without Planning for the Tax
Some investors take boot intentionally — they need liquidity, or the math on the replacement just does not work out. That is a valid choice. The mistake is not accounting for the tax. Boot is taxable in the year of the exchange, and if you have spent the $40,000 you took out, you may not have cash to pay the $12,000–$15,000 tax bill when April comes. Set aside at least 30–40% of any boot you accept to cover federal and state taxes. Using the capital gains tax calculator gives you an estimate the day you structure the deal.
For a broader look at how depreciation affects your tax picture, our real estate depreciation guide explains how accumulated depreciation flows through to recapture — and why it makes boot expensive faster than most investors expect.
Disclaimer: This article is for informational purposes only and does not constitute legal, tax, or financial advice. Tax laws change frequently, and every investor’s situation is unique. Consult a qualified CPA, tax attorney, or financial advisor before structuring any 1031 exchange. The calculations shown are illustrative examples and should not be relied upon as precise tax determinations for your specific transaction.
Frequently Asked Questions About 1031 Exchange Boot
What is 1031 exchange boot and how is it taxed?
1031 exchange boot is the portion of an exchange that does not qualify for tax deferral — typically cash you receive, net debt relief from a smaller mortgage on the replacement property, or non-like-kind property. Boot is taxed as capital gain in the year of the exchange. Depreciation recapture (25%) is applied first, then long-term capital gains (15% or 20%), plus the 3.8% Net Investment Income Tax for high earners, plus applicable state taxes.
Does receiving any boot disqualify the entire 1031 exchange?
No. Receiving boot does not void the exchange. Only the boot amount is taxed; the rest of your realized gain remains deferred. A partial exchange is still usually far better than a straight taxable sale, especially when the deferred gain is large.
What is mortgage boot in a 1031 exchange?
Mortgage boot (also called debt relief boot) occurs when the mortgage on your replacement property is less than the mortgage on your relinquished property. The IRS treats the reduction in debt as if you received cash. For example, if you sold a property with a $200,000 mortgage and bought a replacement with a $120,000 mortgage, you have $80,000 in mortgage boot — even if you reinvested every dollar of equity.
Can I offset 1031 exchange boot with cash?
Yes. You can offset 1031 exchange boot by adding cash from outside the exchange to the replacement property closing. Each dollar of outside cash you bring reduces your boot by one dollar. For example, if you have $80,000 in mortgage boot, bringing $80,000 in additional cash to the closing eliminates the boot entirely. The cash can come from savings, a HELOC on another property, or any non-exchange source.
What costs can be paid from exchange funds without creating boot?
Qualified exchange expenses include brokerage commissions, title insurance premiums, recording fees, transfer taxes, and attorney fees directly related to the exchange. Non-qualifying costs include loan origination fees, mortgage points, prepaid insurance, property tax prorations, and security deposit credits. Paying non-qualifying costs from exchange funds creates dollar-for-dollar cash boot.
How do I report 1031 exchange boot on my tax return?
Boot from a 1031 exchange is reported on IRS Form 8824 (Like-Kind Exchanges). The taxable gain (boot) flows from Form 8824 to Schedule D and, for depreciation recapture, to Form 4797. Your Qualified Intermediary will provide a closing statement showing the boot amount. Your CPA or tax advisor uses those figures to complete the forms. Be sure to file Form 8824 even for a perfect exchange with no boot — failing to file can trigger IRS inquiries.
Is boot from a 1031 exchange subject to depreciation recapture?
Yes, and this is the most expensive part. The IRS allocates boot to the highest-taxed gain first. If you have taken depreciation deductions on the property — and most investors have — the first portion of your boot up to the total accumulated depreciation is taxed at 25% under Section 1250 unrecaptured gain rules. Only boot above that threshold gets the more favorable long-term capital gains rate of 15% or 20%. For more on how depreciation flows through your tax return, see our depreciation guide.
Further Reading and Resources
- IRS Publication 544 — Sales and Other Dispositions of Assets (official IRS rules for Section 1031 exchanges)
- Investopedia — What Is Boot? (plain-language overview of boot in like-kind exchanges)
- BiggerPockets — 1031 Exchange Guide (investor-focused resource with community discussion)
- ArvCalc — Complete 1031 Exchange Guide for Real Estate Investors
- ArvCalc — 1031 Exchange Timeline and Deadlines Guide
- ArvCalc — How to Avoid Capital Gains Tax on Investment Property
Leave a Reply