Short answer
In a delayed 1031 exchange you must identify replacement property in writing within 45 days of selling, and receive it by the earlier of 180 days after the sale or your tax return due date, including extensions. Both clocks start on the closing date of the property you sell.
1. The two deadlines
| Rule | Deadline | What you must do |
|---|---|---|
| Identification | 45 days after the sale | Identify replacement property in a signed written document sent to the appropriate person |
| Exchange period | Earlier of 180 days or your return due date (with extensions) | Receive the replacement property |
If you receive the replacement property within the 45 days, you are automatically treated as having met the identification requirement. The 180 days run at the same time as the 45 days, not after them.
2. Example dates
The table counts calendar days from the closing date of the property you sold.
| Closing date | Day 45 | Day 180 | Which limit applies |
|---|---|---|---|
| 15 Nov 2026 | 30 Dec 2026 | 14 May 2027 | Return due date, if earlier (15 April 2027 unless you extend) |
| 18 Dec 2026 | 1 Feb 2027 | 16 Jun 2027 | Return due date, if earlier (15 April 2027 unless you extend) |
| 1 Mar 2027 | 15 Apr 2027 | 28 Aug 2027 | Day 180 (the 2027 return is due in 2028) |
For a sale late in the year, the tax return due date can fall before day 180. Filing an extension can protect your full 180 days, so talk to your adviser before year end. The calculator shows both dates from your closing date; the return due date check is up to you.
3. The three identification rules
- 1Three-property rule: identify up to three potential replacements, whatever their value.
- 2200% rule: identify more than three if their combined value is no more than 200% of what you sold. At an $850,000 sale that is $1,700,000.
- 395% rule: if you exceed both, you must acquire at least 95% of the total value you identified.
4. What happens if you miss a deadline
If a timing requirement is not met, the deferred exchange does not qualify. The gain is generally taxable in the year you transferred the old property, including depreciation recapture. A qualified intermediary that causes a failure can also leave you with tax due, so confirm dates in writing at closing.
5. Deadline checklist
- 1Choose a qualified intermediary before closing the sale. Your own agents and related parties cannot act as one.
- 2Write down the closing date and calculate day 45, day 180 and your return due date.
- 3Send a signed identification notice before day 45, and keep proof of delivery.
- 4Close on the replacement property before the earlier of day 180 or your return due date.
- 5File Form 8824 with the return for the year of the sale.
6. Check your own numbers
The deadlines only matter if the exchange also avoids boot. Replacing at least the net sale price and your debt keeps the gain deferred. On the calculator defaults, a $850,000 sale with a $950,000 replacement defers $156,022 of tax, but buying a $700,000 property with a $100,000 mortgage would leave about $94,750 of mortgage boot taxable.
7. Frequently asked questions
How long do you have to complete a 1031 exchange?expand_more
You have 45 days from the sale to identify replacement property in writing and until the earlier of 180 days from the sale or the due date of your tax return, including extensions, to receive it. Both periods start on the same day.
Does the 180 days start after the 45 days end?expand_more
No. The 45-day and 180-day periods both start on the date you transfer the property you gave up and run at the same time, so you have about 135 days after day 45 to close.
Can you get an extension on the 45-day deadline?expand_more
The IRS instructions set the 45-day identification period with no extension. Replacement property received within the 45 days is treated as identified, so closing early also meets the rule.
What happens if you miss the 1031 exchange deadline?expand_more
The exchange generally fails and the gain is taxable in the year you sold the old property, including depreciation recapture. Ask your qualified intermediary and tax adviser what options exist.