The 1031 Exchange Timeline: 45 Days to Identify, 180 Days to Close

You have 45 calendar days from the day your sale closes to identify replacement property in writing, and 180 calendar days to close on it, or until your tax return is due, whichever comes first. Both clocks start on the same day. Here is every milestone in order, your exact dates, a worked example, and what happens when a deadline falls on a weekend, a holiday or a disaster.

The 1031 exchange timeline at a glance

Every date in a deferred (forward) exchange is measured from one moment: the day the property you are selling closes. The table below is the whole timeline. Everything after it is detail.

Your dates on one 180-day scale

Enter the date your sale closes (or will close). The two lanes show the identification and exchange periods running side by side from that day, and the cards below state the actual deadline dates. If your tax return for the sale year comes due before day 180, the scale marks that too.

The scale assumes a calendar-year individual whose return is due April 15 of the following year. Partnerships and S corporations file by March 15, so their cap arrives a month earlier. An extension restores the full 180 days in every case.

How long do you have to do a 1031 exchange?

A deferred exchange has a hard time limit of 180 calendar days, with a checkpoint at day 45. Both numbers come straight from the statute. Section 1031(a)(3) of the Internal Revenue Code says replacement property is not like-kind if it is not identified within 45 days after you transfer the relinquished property, or if it is received after the earlier of 180 days or the due date of your return for that tax year. The regulations add the detail that matters in practice: both periods start on the day of the transfer and end at midnight on the 45th and 180th day.

Three things follow from that wording:

• The periods run at the same time, not back to back. Identifying on day 45 leaves 135 days to close, not 180.
• Calendar days, not business days. The regulations count every day. There is no rollover when a deadline lands on a Saturday, Sunday or federal holiday, so most intermediaries treat the last business day before the deadline as the real one.
• The 180 days can be shorter. "Earlier of 180 days or your return due date" means a sale that closes late in the year can leave you far fewer than 180 days unless you file an extension. The worked example below shows exactly how that plays out.

These numbers have not changed since the deferred-exchange regulations were finalized in 1991, and nothing in the 2026 tax year alters them. Anything you read about a "new" 1031 timeline is describing disaster relief or a proposal, not the rule.

A worked example with real dates

Suppose your rental building closes on Friday, November 13, 2026. Counting calendar days:

Now move the closing to Monday, March 2, 2026. Day 45 is Thursday, April 16, 2026, and day 180 is Saturday, August 29, 2026. The return is not due until the following April, so the full 180 days are yours. But day 180 is a Saturday, and closings do not happen on Saturdays. Your real deadline for a recorded closing is Friday, August 28.

The lesson: a spring or summer sale gives you the full six months. A sale that closes from mid-October onward gives you less unless you extend, and the extension must be filed before the original due date. The deadline calculator flags this automatically for any closing date.

The milestones, in order

The 45-day identification period in detail

Day 45 is the most-missed deadline in 1031 exchanges. Three rules about it:

• Calendar days, not business days. If day 45 lands on a Sunday or a holiday, it still expires at midnight that day.
• Delivery to the QI, not intent. It does not matter when you decided. The written identification must be received by the QI (or another party to the exchange who is not you and not disqualified) before midnight on day 45.
• No routine extensions. Only IRS disaster relief (Rev. Proc. 2018-58, Section 17) can postpone it, and eligibility is broader than the property's location: it also covers exchanges where a party to the transaction, the lender or the title company sits in the covered area.

The identification document itself

It must be in writing, signed by the taxpayer, delivered to the QI (not your agent, not your attorney, not the seller), and describe each property unambiguously: a street address, a legal description, or a distinguishable name for a named building. Fax, email with confirmed delivery, or overnight courier all work. You may revoke and replace an identification in the same signed, written way at any time before the end of day 45. Most QIs provide a template.

Which identification rule to use

Covered in detail in the rules pillar. Most investors use the three-property rule. The 200% rule is useful when you want a longer shortlist and are not sure which deal will close. The 95% rule is too risky for most situations because you must then acquire nearly everything on the list.

The 180-day exchange period in detail

Day 180 is just as strict. Worth knowing:

• It is 180 days from day 0 (the sale closing), not from day 45. The two clocks run simultaneously from the same start. You have 135 days after identification to close.
• "Closed" means title has transferred. A signed contract, a lender commitment or funds in escrow on day 180 do not count. The deed must be delivered and, in practice, recorded.
• If your tax return is due before day 180 without an extension, the earlier date controls. For calendar-year individuals that is April 15; for partnerships and S corporations it is March 15. Filing the extension (Form 4868 for individuals, Form 7004 for entities) before the due date preserves the full 180 days.
• You can only close on what you identified. If every identified property falls through after day 45, the exchange fails and the QI returns the funds, which are then taxable.
• Reverse exchanges have a parallel 180-day rule: 180 days for the parked property to leave the exchange accommodation titleholder after it is first parked.

Can a 1031 exchange deadline be extended?

Not for the reasons investors usually ask about. A lender that slips, a seller who backs out, an inspection that turns up a problem, an illness in the family: none of these move day 45 or day 180. The IRS has no discretionary extension for exchange deadlines, and neither does your qualified intermediary.

The one exception is federally declared disaster relief. Under Section 17 of Rev. Proc. 2018-58, when an IRS news release or notice grants relief for time-sensitive acts in a disaster area, a 1031 exchanger who qualifies may postpone a 45-day or 180-day deadline that falls on or after the disaster date. Three conditions apply:

1. You must be an "affected taxpayer" under the notice, or meet one of the listed difficulty tests, for example the relinquished or replacement property, a party to the transaction, the lender or the title company being in the covered area.
2. The relinquished property must have closed on or before the disaster date (for a reverse exchange, the parked property must have been transferred to the exchange accommodation titleholder by then).
3. The postponement is the later of 120 days or the end date in the notice, but it can never run past the due date of your return, including extensions, or one year from the original deadline.

The relief is not automatic and it is not limited to the property's own ZIP code. Read the disaster-relief explainer, then verify the specific notice at irs.gov before you rely on it.

Reverse and improvement exchange timelines

The same 45 and 180 numbers govern the other two exchange structures, but the clocks start from a different event.

Reverse exchange

In a reverse exchange you buy the replacement property before you sell. Because you cannot own both at once, an exchange accommodation titleholder (EAT) takes title to one of them under the safe harbor in Rev. Proc. 2000-37. From the day the EAT takes title: you have 45 days to identify the property you will sell, and the parked property must leave the EAT within 180 days. The 180 days is a total for the parking arrangement, not a separate period for each property. Details and costs are on the reverse exchange page.

Improvement (construction) exchange

When you want to use exchange funds to build or renovate, the EAT holds the replacement property while the work happens. The property, with its improvements, must be transferred to you by day 180 counted from your sale closing (or from the parking date in a reverse structure). Only improvements that are actually completed by day 180 count toward the value you must acquire; money spent on work finished after that date is boot. Identification by day 45 must describe the improvements as well as the land. See the improvement exchange page for how the 180-day construction window is planned.

Pre-closing prep: the 2-4 week lead time

Before day 0, your QI needs:

• A copy of the purchase and sale agreement for the relinquished property
• The draft settlement statement from the title company
• Assignment-of-rights language inserted into the PSA
• The exchange agreement, signed by you
• Wire instructions for the exchange account, delivered to the closing agent
• Your entity documents if you are exchanging in an LLC or trust

Typical lead time: two weeks for a simple forward exchange, four to six weeks for a reverse. Never engage the QI the week of closing. Something will be missed.

Timing traps that kill exchanges

1. Starting the QI conversation after going under contract

The sale contract often needs assignment language. Adding it after signature requires an amendment the buyer may not sign. Get the QI engaged before the listing agent sets pricing.

2. Assuming financing will close on time

Lenders on the replacement property often do not understand 1031 deadlines. Build in at least 14 days of buffer before day 180. If your lender cannot commit to a hard close date, that is a problem.

3. Losing your primary replacement without backups

If your first-choice property falls through after day 45, you can only close on something else you identified. This is why the three-property rule is useful: identify two or three options, not just the one you want.

4. Not filing a tax extension when the exchange runs past April

Sale in November, replacement closing scheduled for May: your return is due April 15, before day 180. File the extension early to preserve the full period. If the exchange will still be open on the due date, file the extension, not the return.

5. Treating a weekend deadline as if it rolls forward

It does not. If day 45 is a Saturday, the identification must be in the QI's hands by Saturday at midnight. If day 180 is a Sunday, the closing has to be complete on the Friday before. Plan every deadline to the last business day, not the calendar day.

6. Assuming disaster relief applies automatically

When the IRS issues disaster relief that covers time-sensitive acts, Section 17 of Rev. Proc. 2018-58 can postpone both deadlines, but you must qualify under the notice and the relinquished property must have closed on or before the disaster date. Verify before you rely on it.

Questions investors ask about the timeline

Have a different question? Browse the 1031 FAQ, 42 questions, each answered directly →

Sources

• 26 U.S.C. §1031(a)(3): the 45-day identification and 180-day (or return due date) receipt requirements.
• Treas. Reg. §1.1031(k)-1: (b)(2) the identification and exchange periods begin on the transfer date and end at midnight on day 45 and day 180; (c) the manner of identification, the three-property, 200% and 95% rules, and revocation.
• Rev. Proc. 2018-58, Section 17: postponement of 1031 deadlines under federally declared disaster relief.
• Rev. Proc. 2000-37: the reverse-exchange parking safe harbor and its 45-day and 180-day limits.
• Instructions for Form 8824: reporting the exchange, and the "earlier of 180 days or the due date of your return, including extensions" rule.