Section 1031 of the federal tax code lets an investor defer capital gains tax by exchanging one investment or business real property for another of like kind, per IRS guidance on like-kind exchanges. The property must be held for investment or business use, not personal use, and the replacement must be identified within 45 days and received within 180 days of the sale. This is information about how the mechanism works, not tax or legal advice; a qualified tax professional should evaluate any specific exchange.
The provision dates to 1921 and rests on a simple premise: trading one investment property for a similar one does not change an investor's economic position enough to justify taxing it immediately, according to National Association of Realtors background on the rule. Since 2018, it applies only to real property — machinery, vehicles, and other personal property no longer qualify, per the IRS.
Every exchange, related-party or not, is reported to the IRS on Form 8824, filed with the tax return for the year the exchange took place, according to the instructions for that form. The form is where the deferred gain, the carried-forward basis, and any boot received are documented for the record.
What Property Qualifies for a 1031 Exchange?
Real property qualifies if it is held for investment or used in a trade or business; a primary residence does not, and property held primarily for resale, such as a house flip, does not either, according to IRS Publication 544. An apartment building can exchange for raw land, a retail strip can exchange for a warehouse, and improved property can exchange for unimproved property, because the IRS defines "like-kind" by nature and character rather than by grade, quality, or use within real estate.
A lease of real property with 30 years or more remaining, including renewal options, can also count as like-kind replacement property, per IRS guidance. One firm restriction: property located outside the United States cannot exchange for property located inside it, since domestic and foreign real property are not considered like-kind to each other.
How Do the 45-Day and 180-Day Deadlines Work?
An investor has 45 days after transferring the relinquished property to formally identify a replacement, and 180 days — or the due date of that year's tax return, including extensions, if earlier — to receive it, according to the IRS instructions for Form 8824. Both clocks start on the same date, the day the original property changes hands, and they run concurrently rather than back to back.
If the replacement property is actually received before the 45-day window closes, the identification requirement is automatically satisfied by the receipt itself, per the IRS. There is no extension built into the rule for weekends, holidays, or a slow closing; the exchange fails on the missed date, not on the reason for missing it.
| Deadline | Clock starts | What must happen |
|---|---|---|
| 45-day identification period | Date the relinquished property transfers | Replacement property formally identified |
| 180-day exchange period | Same date as above | Replacement property received, or tax-return due date if earlier |
What Counts as "Boot," and Why Does It Trigger Tax?
"Boot" is any cash or non-like-kind property an investor receives alongside the exchange, and receiving it triggers taxable gain up to the value of that cash or property, per IRS guidance on like-kind exchanges. Net liabilities assumed by the other party can also count as boot, reduced by exchange expenses, according to the Form 8824 instructions.
The rule runs only one direction: boot can create recognized gain, but it cannot be used to recognize a loss. An investor who exchanges into a lower-value property and pockets the difference in cash owes tax on that cash portion in the year of the exchange, even though the rest of the exchange remains deferred.
An illustration using the mechanics above: an investor who exchanges a property carrying a $300,000 basis for a replacement worth $450,000, and also receives $20,000 in cash at closing, recognizes taxable gain on that $20,000 boot in the exchange year. The remaining gain built into the $130,000 difference in value stays deferred, carried forward in the replacement property basis rather than taxed immediately.
How Does an Exchange Affect Basis and Future Gain?
Basis is the figure used to calculate taxable gain when a property eventually sells. In a like-kind exchange, the replacement property generally takes the same basis as the property given up, increased by any additional cash paid, per IRS Publication 544.
That carryover basis is the mechanism behind the word "defer" rather than "eliminate." The gain that would have been taxed at the time of the original sale is instead built into the new property's lower basis, which means it resurfaces as taxable gain whenever that replacement property is eventually sold outright rather than exchanged again.
What Are the Related-Party Rules?
A related party includes a spouse, child, grandchild, parent, grandparent, sibling, or a related corporation, partnership, trust, estate, or tax-exempt organization, according to the IRS instructions for Form 8824. Exchanges between related parties require Form 8824 to be filed for the exchange year and for each of the two years that follow.
If either party disposes of the property received in the exchange before two years have passed since the last transfer, the deferred gain must generally be reported as income in the year of that early disposition, with limited exceptions, per the IRS. The two-year hold is the mechanism that prevents related parties from using an exchange simply to reset basis between each other without an economic transaction taking place.
Who Actually Uses 1031 Exchanges?
The provision is not confined to large institutional owners. Only about 5 percent of recently exchanged properties were held by corporations, according to National Association of Realtors data, indicating that individual investors and smaller entities account for the large majority of exchange activity.
NAR also notes that the provision has periodically drawn legislative attention; a prior federal budget proposal floated capping annual like-kind deferrals at $500,000 per taxpayer as a way to help fund other spending. No such cap is currently in effect, and any future change to the provision would need to move through Congress.
NAR also frames the incentive effect directly: "The great majority of properties now swapped under the like-kind exchange would not be sold if tax was due," the organization states, arguing that the deferral changes the timing decision itself rather than only the tax bill. That is a trade association's characterization of the provision's effect, not an independently verified market statistic.
Frequently Asked Questions
- Does a 1031 exchange eliminate capital gains tax? No. It defers the tax by carrying the original basis into the replacement property, per IRS guidance; the deferred gain is generally taxed when the replacement property is later sold without another exchange.
- Can a primary residence use a 1031 exchange? No. The property must be held for investment or business use; property used for personal purposes, such as a primary residence, does not qualify, according to IRS Publication 544.
- What happens if the 45-day deadline is missed? The exchange generally fails and the sale is treated as a taxable transaction, since the IRS deadlines run from the transfer date with no stated extension for missed dates.
- Is cash received in an exchange taxable? Yes, up to its value. Cash or non-like-kind property received alongside an exchange is boot and is taxable to the extent of its value, per the IRS instructions for Form 8824.
For a related property news perspective, read How a 1031 Exchange Lets Landlords Defer Capital Gains Tax.