1031 Exchange Deadlines: 45 Days to Pick, 180 Days to Close

TL;DR: In a 1031 exchange, the clock starts the day your relinquished property closes. You have 45 calendar days from that date to formally identify replacement property in writing, and 180 calendar days total (not 180 days after the 45) to close on the replacement. Miss either window and the exchange fails, turning your deferred gain into a taxed one — confirm exact dates, weekends, and any disaster-relief extensions with your qualified intermediary and IRS.gov before you rely on them.

_Last reviewed: August 2026 · 7 min read_

You sold a rental, a qualified intermediary is holding your proceeds, and now two clocks are running at once. Landlords lose 1031 exchanges more often to missed paperwork deadlines than to bad property choices, so knowing exactly when each clock starts and what counts as "identified" matters as much as the deal itself.

Okoniq Property Hub helps landlords log closing dates, identification letters, and replacement-property documents in one place so nothing slips past a 45-day or 180-day cutoff.

When does the 45-day identification period actually start?

The 45-day clock starts on the day the relinquished property closes and title transfers, not the day you sign a purchase contract on the replacement or the day you decide to do an exchange. Every calendar day counts toward the 45, including weekends and holidays — this is not 45 business days.

Within that window you must deliver a written identification of the replacement property or properties to your qualified intermediary (or another party specified in the exchange agreement). "I'm thinking about that duplex on Maple Street" said out loud to your agent does not satisfy the requirement. The identification needs to unambiguously describe the property — a street address or legal description is standard practice, and most qualified intermediaries provide a form for this exact purpose. If you're new to the mechanics of a like-kind exchange altogether, 1031 Exchanges — A Landlord's Introduction covers the setup steps that come before this clock even starts, including why you need a qualified intermediary in place before closing on the sale.

How does the 180-day exchange period relate to the 45 days?

The 180-day period is not "45 days plus another 180 days" — it runs concurrently, starting the same day as the 45-day clock, from the relinquished property's closing. That means your 180 days already includes the 45 days used for identification. In practice, once identification is done, you typically have the remaining balance of the 180-day window to actually close on the replacement property.

There's also a second boundary worth knowing: the 180 days can be shortened by your tax return due date. If your tax filing deadline (including extensions) for the year of the sale falls before day 180, the exchange period ends on that earlier date unless you file an extension. This is one of the most common ways landlords accidentally compress their own timeline — selling late in the year without confirming their filing deadline lines up with the full 180 days.

What happens if you miss the 45-day or 180-day deadline?

Missing either deadline generally disqualifies the exchange, and the transaction reverts to a taxable sale. If day 45 passes without a valid written identification on file, you cannot add or substitute replacement property after that point — you're locked into whatever you identified, or you have nothing identified and the exchange fails. If day 180 (or the earlier tax-filing cutoff) passes without closing on the identified replacement, the exchange also fails, and your capital gain and any depreciation recapture become taxable in the year of the original sale.

There is limited flexibility for federally or state-declared disasters, where the IRS has at times granted postponements to the 45-day and 180-day windows for taxpayers in affected areas. These are announced case by case and are not automatic, so don't assume relief applies to your situation — check current IRS.gov disaster relief notices or ask your qualified intermediary directly.

| Deadline | Starts | What's required | Consequence of missing it | |---|---|---|---| | Identification period | Day of relinquished property closing | Written, unambiguous identification delivered to QI | Cannot add new replacement property after this date | | Exchange period | Same day as identification period (runs concurrently) | Close on identified replacement property | Exchange fails; gain becomes taxable in year of sale |

How do you correctly identify replacement property within 45 days?

You identify replacement property by naming it precisely, in writing, and delivering it to the right party before day 45 expires. The IRS allows identifying more than one property under specific rules — commonly known as the "three-property rule" (up to three properties regardless of value) or the "200% rule" (any number of properties, as long as their combined fair market value doesn't exceed 200% of what you sold). These are structural rules under the identification regulations, and your qualified intermediary will walk you through which one fits your situation — the exact percentage and property-count thresholds are worth confirming directly against current IRS guidance before you finalize a letter, since misapplying them can invalidate the identification.

Keep a paper trail. Save the dated identification letter, the delivery confirmation (email timestamp, fax confirmation, or certified mail receipt), and any amendments. If you're exchanging out of a property you inherited or converted from a primary residence, your basis calculation carries into this process too — see how to calculate cost basis on an inherited house or converting a rental to a primary residence if either applies to your chain of ownership.

Who actually tracks these deadlines, and what if I'm doing this alone?

Your qualified intermediary tracks the calendar, but you're the one who has to act on it. Most QIs will send reminders as day 45 and day 180 approach, but the legal responsibility for delivering a valid identification and closing on time sits with you as the taxpayer. Landlords selling from out of state, or handling multiple relinquished properties in a single exchange, should build in buffer days rather than aiming to close exactly on day 180 — title delays, lender delays, and appraisal delays don't extend the deadline.

If you're a non-resident owner running the exchange from abroad, factor in that a sale may also trigger FIRPTA withholding considerations that run on a separate track from your 1031 timeline and require their own paperwork before closing.

FAQ

Does the 45-day clock pause for weekends or holidays?

No. Both the 45-day and 180-day periods are counted in calendar days, including weekends and federal holidays, starting from the closing date of the relinquished property.

Can I change my identified replacement property after day 45?

No. Once the 45-day identification period ends, you're limited to the property or properties you identified in writing during that window — you cannot substitute a new property after that date.

Does my tax filing deadline ever cut the 180 days short?

Yes, it can. If your tax return due date (including extensions) for the year of the sale falls before day 180, the exchange period ends on that earlier date unless you've filed for an extension — confirm your specific filing deadline with a CPA.

What if I only identify one property and the deal falls through?

If the identified property purchase collapses and you have no other valid identification on file, the exchange typically fails and the transaction is treated as a taxable sale, with your gain recognized in the year of the original sale.

Do disaster declarations ever extend these deadlines?

Sometimes. The IRS has issued postponements to the 45-day and 180-day windows for taxpayers in federally or state-declared disaster areas in the past, but relief is announced per event and isn't automatic — check current IRS.gov notices or ask your qualified intermediary if you think you qualify.

This is educational information, not tax or legal advice. This post assumes a standard, single relinquished-property 1031 exchange and does not account for disaster-relief extensions, multi-property structuring rules, your specific tax filing deadline, your state's conformity to federal exchange rules, or legislation after July 2026. Talk to a licensed CPA and your qualified intermediary before acting on anything here, and confirm current figures on IRS.gov.

<div class="glass rounded-2xl p-5 mt-7 max-w-4xl border border-red-400/30 bg-red-500/5"> <div class="flex items-start gap-3"> <span class="text-2xl flex-shrink-0">⚠️</span> <div class="flex-1 min-w-0"> <p class="text-red-200 text-sm font-bold">Not tax advice</p> <p class="text-slate-300 text-xs mt-1 leading-relaxed"> This post assumes a standard single-property 1031 exchange under the general 45-day and 180-day framework. It does not account for disaster-relief postponements, multi-property identification rules, your specific tax filing deadline, your state's rules, your entity type, or legislation after July 2026. Tax rules change and depend on your specific situation. Talk to a licensed CPA before acting on anything here, and confirm current figures on IRS.gov. </p> </div> </div> </div>