1031 Exchange Basics: How Investors Defer Capital Gains Tax on a Sale
Sell an investment property at a profit and the IRS expects a share of it — capital gains tax, plus depreciation recapture if you've owned it a while. On a property that's appreciated significantly, that bill can run into six figures.
A 1031 exchange lets you defer that tax bill by rolling the proceeds into another investment property instead of cashing out. The gain doesn't disappear — it carries forward into the new property's cost basis — but you keep the full amount of equity working for you today instead of handing a chunk of it to the IRS at closing.
Named for Section 1031 of the tax code, this is one of the main tools serious investors use to move from a duplex to a fourplex to an apartment building without shrinking their capital base at every step.
Why It Matters
Every time you sell and pay tax, you're compounding from a smaller number. Defer that tax instead, and 100% of your equity moves into the next deal.
Run that difference across two or three trades over a decade and it's the gap between growing a portfolio and standing still on it.
What Qualifies
A 1031 exchange only works under a specific set of conditions:
- The property must be held for investment or business use. A rental, a commercial building, or bare land held for appreciation qualifies. A primary residence does not.
- The replacement property must also be real property held for investment or business use. Since the 2017 tax law changes, only real estate qualifies for 1031 treatment — equipment, vehicles, and other personal property no longer do.
- "Like-kind" is broader than most investors expect. Any real property qualifies as like-kind to any other real property. You can sell a single-family rental and buy raw land, a retail strip, or a multifamily building — the exchange doesn't require a similar property type, just similar use as an investment.
- Flips generally don't qualify. The IRS looks at intent. Property bought and renovated with the plan to resell quickly is treated as inventory, not investment property, even if you technically held title for a while.
If there's any doubt about whether a specific property or situation qualifies, that's a conversation for a CPA or 1031 exchange attorney before you list the property — not after.
The Two Deadlines That Make or Break the Exchange
A 1031 exchange runs on a strict clock that starts the day the relinquished property closes:
- 45 days to identify replacement property. You must identify, in writing, the property or properties you intend to acquire, and deliver that identification to your qualified intermediary. Miss this deadline and the exchange fails — there's no extension for being close.
- 180 days to close on the replacement property. This is not 45 days plus 180 days — the 180-day window includes the 45-day identification period. The clock runs from the same closing date, and both deadlines apply simultaneously, not sequentially.
Both deadlines are calendar days, not business days, and neither moves if the deadline lands on a weekend or holiday. The only common exception is a federally declared disaster affecting the property's location, which can trigger an automatic extension.
Why You Need a Qualified Intermediary
You cannot receive the sale proceeds directly at any point in the exchange, even briefly. Touching the money — even depositing it and immediately reinvesting it — disqualifies the entire exchange and makes the gain taxable.
A qualified intermediary (QI) is a neutral third party who holds the proceeds between the sale of the relinquished property and the purchase of the replacement property. The QI needs to be lined up before the relinquished property closes, not after — it can't be arranged retroactively once funds have already changed hands.
Identification Rules When Naming Multiple Properties
Investors rarely identify just one replacement property, since deals fall through. The IRS allows three ways to identify multiple candidates within the 45-day window:
| Rule | What It Allows |
|---|---|
| Three-Property Rule | Identify up to 3 properties, regardless of their combined value |
| 200% Rule | Identify any number of properties, as long as their combined value doesn't exceed 200% of what you sold |
| 95% Rule | Identify any number of properties, but you must ultimately acquire at least 95% of their combined identified value |
Most exchanges use the three-property rule because it's the simplest to stay compliant with.
How Much of the Gain Actually Gets Deferred
Full deferral requires reinvesting equal or greater value and equal or greater debt than what you sold — or making up any shortfall in debt with additional cash.
Take out equity, buy a cheaper replacement property, or pay off debt without replacing it, and the difference is called "boot." Boot is taxable in the year of the exchange, even though the rest of the transaction is deferred. A 1031 exchange isn't all-or-nothing — you can do a partial exchange and pay tax on the boot while still deferring the rest.
Common Mistakes
- Lining up the qualified intermediary too late — after the relinquished property has already closed and funds have moved
- Missing the 45-day identification deadline because a "sure thing" replacement property fell out of contract
- Assuming a flip qualifies when the IRS would view the intent as resale, not investment holding
- Buying down in value or debt without realizing the difference becomes taxable boot
- Mismatched title vesting — the same taxpayer generally needs to appear on both the relinquished and replacement property deeds
How ProfitTrackr Helps
A 1031 exchange only pencils out if the replacement property actually performs as well as, or better than, the one you're selling. Before you commit to a 45-day identification window, run the replacement property through Prospects to confirm its cash-on-cash return, cap rate, and equity position hold up against the property you're giving up.
Once the exchange closes, add the new property to Owned and keep its income and expense history connected to the original — so when it's time to sell again, you have a clean record of performance across the full chain of properties, not just the most recent one.
Key Takeaways
- A 1031 exchange defers capital gains tax by rolling sale proceeds into another investment property — it doesn't eliminate the tax, it postpones it
- Only real property held for investment or business use qualifies; primary residences and flips generally don't
- The 45-day identification deadline and 180-day closing deadline run concurrently from the same start date, with no extensions for missed timing
- A qualified intermediary must hold the proceeds — touching the money yourself disqualifies the exchange
- Reinvest equal or greater value and debt to defer the full gain; anything less creates taxable "boot"
Related articles: ARV Explained: How to Calculate After Repair Value | The BRRRR Strategy Explained | Cap Rate vs. Cash-on-Cash Return