Day zero is the closing of your sale. You have 45 calendar days to deliver a written, signed identification of replacement property to your QI, and 180 calendar days to close — no extensions, no mercy for weekends or holidays, and a hidden trap where your tax-filing deadline can shorten the 180. Identify more than one property, use the identification rules strategically, and have a backup that can close fast.
Both deadlines start the day your relinquished property closes — not when you list it, not when you find a buyer, not when the money reaches your QI. From that day: 45 calendar days to identify replacement property in writing, and 180 calendar days (running concurrently, not consecutively) to receive it. Day 45 falling on Christmas doesn't help you. There are no extensions for cold feet, failed financing, or a seller who ghosts — the only extensions ever granted are IRS disaster relief for federally declared disasters.
Identification must be written, signed by you, and delivered by midnight on day 45 to your qualified intermediary (or another permitted party who isn't your agent). It must describe each property unambiguously — a street address or legal description. "A multifamily property in the Carolinas, around $2M" identifies nothing and fails.
You can identify multiple properties, under one of three rules:
The 3-property rule. Identify up to three properties of any value; buy any or all. This is what most exchangers use, and the strategic point most miss: identifying only one property means one inspection surprise, one financing hiccup, one difficult seller stands between you and a full tax bill. Use all three slots.
The 200% rule. Identify any number of properties, as long as their combined value doesn't exceed 200% of what you sold. Useful when diversifying into several smaller assets — including multiple DSTs.
The 95% exception. Identify more than three properties exceeding 200% of value — but then you must actually acquire 95% of the total value identified. In practice this is a trap with a door prize; almost nobody uses it on purpose.
Until day 45 you may revoke and replace identifications freely (in writing, same delivery rules). At 12:01 a.m. on day 46, the list is carved in stone.
The backup-slot strategy: even when your primary target is a building you're already under contract on, list a pre-packaged option — commonly a DST — in slot two or three. It costs nothing to identify, and it converts "the deal fell through on day 130" from a six-figure tax event into an inconvenience. This single habit would have saved more failed exchanges than any other advice on this site.
You must receive the replacement property — close, take title — within 180 days of your sale. But the statute actually says 180 days or the due date of your tax return for the year of the sale, whichever comes first.
Sell on November 20th. Your 180 days run into May. But your Form 1040 is due April 15th — and if you file it, or the deadline passes, before completing the exchange, your window slams shut early. The fix is trivial if you know it exists: file an extension. Every exchanger who sells in Q4 should have this circled in red. Every year, some don't.
Rarely on the deadline itself — usually upstream, through behavior. The most common patterns we've watched over a decade:
Starting the search after closing. Forty-five days is not a shopping period; it's a confirmation period. The search should begin when you list your property, not when you sell it. Identification too vague to survive scrutiny. An address typo or a casually-worded letter becomes an audit argument years later. Your QI has a form; use it precisely. Deadline-induced overpaying. The market can smell an exchanger on day 38. Sellers hold firm, and buyers rationalize overpaying by the size of the tax deferred — trading a one-time tax bill for a permanently impaired asset. The single-identification gamble, covered above, still the leading cause of death.
Before your sale closes: QI engaged and funded instructions in place; search already running for weeks; financing pre-approved for the target price range; calendar entries for day 40 (identification finalized), day 45 (delivered and confirmed received), and your tax-filing deadline; and a fast-close backup selected for the identification list. Boring, mechanical, and worth more than any market insight.
Yes. Calendar days, midnight cutoff, no exceptions short of a federally declared disaster in your area.
Yes — and you should still fill your remaining slots with backups.
The exchange fails, your QI returns funds after the exchange period ends, and the sale is taxed normally. Note the timing wrinkle: if funds come back to you the following calendar year, installment-sale rules may at least push the tax into that year. Ask your CPA before assuming.
No one can. Not your QI, not your CPA, not a sympathetic IRS agent. The dates are statutory.
A free, no-obligation introduction to a vetted 1031 or DST partner — with our referral relationship disclosed in writing. On the 45-day clock? Same-day attention.