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1031 Exchange Deadline Calculator

Your 45-day identification and 180-day closing deadlines, counted from the day the property you sold closed.

How it works

Under IRC §1031(a)(3), both periods start the day the relinquished property transfers. Replacement property must be identified in writing within 45 days, and received within 180 days or by the due date of your tax return for that year, including extensions, whichever is earlier. Days are calendar days, and a deadline on a weekend or holiday stays where it falls.

identify by = sale date + 45 days; close by = earlier of (sale date + 180 days, tax return due date)
Sale date
Closing date of the property you sold (relinquished property)
Day 45
Written identification to your qualified intermediary by midnight
Day 180
Last day to close on the replacement property
Return due date
April 15, or October 15 with an extension, for individuals

Worked example

The property you sold closed on September 15, 2026, and you plan to extend your 2026 return.

  1. 1Day 45: September 15 + 45 days = October 30, 2026
  2. 2Day 180: September 15 + 180 days = March 14, 2027
  3. 3Return due with extension: October 15, 2027, which is later than day 180

Identify by October 30, 2026 and close by March 14, 2027.

Frequently asked questions

Why does filing an extension matter for a 1031 exchange?

The exchange period ends at the earlier of day 180 or your return's due date. If you sell late in the year, say December 1, 2026, day 180 falls on May 30, 2027, after the April 15 deadline. Without an extension, your exchange period ends on April 15. Filing an extension moves the due date to October so you get the full 180 days.

What are the identification rules?

Most investors use the three-property rule: identify up to three properties of any value. The 200% rule allows more, as long as their combined value is no more than twice what you sold. The 95% rule allows any number if you actually acquire 95% of the total value identified. Identification must be written, signed, and unambiguous, such as a street address or legal description.

Do the 45 and 180 days run one after the other?

No. Both start on the same day and run at the same time. The 45-day identification period is the first part of the 180-day exchange period, not an addition to it, so after identifying you have 135 days left to close, not 180.

What if a deadline falls on a weekend?

Unlike most tax deadlines, the 1031 periods do not move to the next business day. If day 45 is a Sunday, identification must be delivered by midnight that Sunday, so plan to send it several days early.

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