Sellers who want to defer capital gains tax on real estate they sell for a profit generally land on one mechanism before any other: Section 1031 of the tax code. It has been part of federal law for decades, applies specifically to investment and business real estate, and works by treating the sale and the purchase of a new property as a continuous transaction rather than two separate taxable events, as long as it is structured correctly.
The Mechanics That Make Deferral Possible
A qualified intermediary, an independent party who is not the seller's agent or a disqualified relative, holds the sale proceeds between the closing of the relinquished property and the purchase of the replacement property. The seller never takes constructive receipt of the cash. From the date the relinquished property closes, the seller has 45 calendar days to formally identify potential replacement properties in writing, and 180 calendar days total to close on the purchase of one or more of them.
Both deadlines run concurrently, not sequentially, and neither can be extended for ordinary reasons like a slow closing or a financing delay. Missing either one converts the transaction back into a fully taxable sale.
What Full Deferral Actually Requires
To defer 100 percent of the gain, the replacement property generally needs to be of equal or greater value than the relinquished property, and the seller needs to reinvest all of the net proceeds and replace any debt that was paid off at the sale, either with new debt or additional cash. Falling short on either value or debt creates what the tax code calls boot, which is taxable in the year of the exchange even though the rest of the transaction is deferred.
An owner who sells a property for $1.5 million with a $600,000 mortgage and buys a replacement for $1.3 million with a $400,000 mortgage has both under-invested cash and under-replaced debt, and will recognize gain on the shortfall even though most of the transaction qualified.
Defer, Not Eliminate
- The gain that would have been taxed at sale is not erased, it is carried forward and attached to the replacement property's basis
- Selling the replacement property later without doing another exchange triggers the original deferred gain along with any new appreciation
- An owner can keep exchanging property after property indefinitely, deferring the same gain repeatedly across a lifetime of ownership
- If the replacement property is instead held until death, heirs generally receive a stepped-up basis, which can turn years of deferral into gain that is never actually taxed to anyone
Where a DST Fits for Owners Who Want Out of Active Management
An owner who wants to defer the gain but is tired of managing tenants, leases, and maintenance can direct exchange proceeds into a Delaware Statutory Trust, a passive, fractional ownership structure that still qualifies as like-kind real estate under Section 1031. DST interests are securities offered through private placement, generally limited to accredited investors, and come with their own illiquidity and fee structure, but they let an owner complete the exchange without taking on another property to actively run themselves.
A 1031 exchange is one option for deferring a real estate gain, not the only one on the table, and it fits best for an owner who wants to keep capital working in real estate rather than cashing out and paying the tax bill up front.
Common Questions
Does a 1031 exchange eliminate capital gains tax permanently?
No. It defers the gain by attaching it to the replacement property's basis. The tax comes due if the replacement property is later sold without another exchange, though holding it until death can pass it to heirs with a stepped-up basis.
Can the 45-day identification deadline be extended?
Generally not for ordinary circumstances like a slow closing or financing delay. Limited extensions have historically been granted only in federally declared disaster areas, and even those are specific to the disaster declaration in effect.
What is boot in a 1031 exchange?
Boot is any value received in the exchange that is not like-kind real property, including cash taken out or debt on the replacement property that is lower than debt on the relinquished property. Boot is taxable in the year of the exchange even though the rest of the gain defers.
Does a 1031 exchange work for a primary residence?
No. Section 1031 applies only to property held for investment or business use, not a primary residence, which instead falls under the separate Section 121 home sale exclusion.
Is a DST a good fit for every 1031 exchange investor?
Not automatically. DST interests are private placement securities generally limited to accredited investors, with illiquidity and fees that differ from owning property directly, and they fit best for an investor prioritizing passive ownership over control of the asset.
