1031 Exchange Timeline for a Late-2026 Sale: The 45 and 180 Days, and Why a Sale After October 17 Gets Fewer

The two clocks, in the regulation's words

Section 1031(a)(3) of the Internal Revenue Code sets the outer limits, and Treasury Regulation 1.1031(k)-1 turns them into dates. The identification period “begins on the date the taxpayer transfers the relinquished property and ends at midnight on the 45th day thereafter.” The exchange period begins on the same date and “ends at midnight on the earlier of the 180th day thereafter or the due date (including extensions) for the taxpayer’s return” for the year of the transfer. The IRS repeats it in the 2025 instructions to Form 8824, the form you file to report the exchange: “The replacement property must be received within 180 days, or by the due date of your tax return (including extensions), whichever is earlier.”

Three things follow from the text, and most deadline mistakes come from one of them:

• The clocks run in calendar days, from the closing of the property you sell. Not from when your qualified intermediary gets the money, and not business days. If you sell several properties in one exchange on different dates, both periods start on the earliest transfer, per IRS Publication 544.
• The 180 days are a maximum. The period also ends on your return's due date, if that comes first. For most of the year it does not. In the fourth quarter it does.
• Neither text says a deadline moves when it lands on a weekend or holiday (our reading of the regulation and the Form 8824 instructions). The only postponement the IRS publishes is for federally declared disasters, below.

Identification has its own rules. It must be designated “in a written document signed by the taxpayer” and sent before the deadline to someone involved in the exchange who is not a disqualified person, such as the intermediary or the seller of the replacement property. You may name up to three properties of any value (the “3-property rule”), or any number whose combined value is no more than twice what you sold (the “200-percent rule”). Name more than that and the identification only survives if you end up receiving at least 95% of the value of everything you named.

Q4 2026: what each closing date leaves you

The table applies the regulation to closings from October 1 to December 31, 2026. Day 45 and day 180 are the transfer date plus 45 and 180 days. The last two columns are the days you actually have if nobody files an extension: an individual's 2026 return is due Thursday, April 15, 2027, and a calendar-year partnership's or S corporation's is due Monday, March 15, 2027. All dates and counts are our arithmetic.

Read the table for two different decisions. The identification deadline is never shortened by the tax return: it is always day 45, and for every closing after November 16, 2026 it falls in 2027, which matters for the year-end cash question further down. The receipt deadline is what the return cuts. For a partnership the cut starts much earlier than most people expect, with any closing from September 17, 2026 (day 180 for a September 16 closing is March 15, 2027, our arithmetic). A rental held in a multi-member LLC that files Form 1065 is usually in this column, not the individual one.

The fix is an extension, and the regulation shows it

The regulation's own example is a late-year sale. A calendar-year corporation transfers property on November 16, 1992. Its identification period ends on December 31, 1992. Then: “The exchange period ends at midnight on March 15, 1993, the due date for M’s Federal income tax return” for that year (March 15 was the corporate due date then). “However, if M is allowed the automatic six-month extension for filing its tax return, the exchange period ends at midnight on May 15, 1993, the day which is 180 days after the date of transfer” of the property.

The same works today. Individuals get “an automatic 6-month extension of time to file the return” by filing Form 4868 (Treas. Reg. 1.6081-4); partnerships get an automatic six-month extension by filing Form 7004 (Treas. Reg. 1.6081-2). With the extension in place before April 15 (or March 15), the due date moves six months later, and day 180 comes first for every Q4 2026 closing.

Two cautions from the same texts. The extension “will not extend the time for payment of any tax due on such return”, so 2026 tax is still due on April 15, 2027 even though the return is not. And the regulation ties the exchange period to the due date, not to the day you happen to file: our reading is that filing early does not shorten it, but filing before the replacement property closes means filing without the Form 8824 the exchange requires, so the usual path is to extend and file after closing.

Disasters: the only postponement the IRS publishes

Rev. Proc. 2018-58, section 17, is the IRS's standing rule for 1031 deadlines in a federally declared disaster. The last day of a 45-day or 180-day period that falls on or after the disaster date is “postponed by 120 days or to the last day of the general disaster extension period” announced for that disaster, whichever is later, but “in no event” past the due date (including extensions) of the return for the year of the transfer, or one year. It covers sellers who transferred the property on or before the disaster date and who are affected taxpayers, or who have difficulty meeting a deadline because of the disaster for reasons the revenue procedure lists, such as the relinquished or replacement property being in the covered disaster area. It is not a general extension, and for a Q4 sale the return-due-date cap still bites unless the return is extended.

The year-end cash question

Your intermediary cannot simply hand the money back when you change your mind. The regulation's safe harbor requires the exchange agreement to deny you the cash until the exchange period ends, with two exceptions: if you identify nothing, the agreement may release the funds “at any time after the end of the identification period”; if you identify property, it may release them after you receive everything you are entitled to, or after certain material contingencies outside your control.

For a closing after November 16, 2026, day 45 is in 2027, so even a quickly abandoned exchange returns the cash in 2027. The regulation's coordination rule with the installment method, 1.1031(k)-1(j)(2), treats a qualified intermediary as not your agent for deciding when you received payment, so in its own example a taxpayer who sold on September 22, 1994 and got leftover cash on March 11, 1995 “may report the $20,000 gain in 1995 under the installment method,” subject to sections 453 and 453A. The rule applies only with a bona fide intent to exchange, which the regulation defines as being “reasonable to believe, based on all the facts and circumstances as of the beginning of the exchange period, that like-kind replacement property will be acquired before the end of the exchange period.” Whether that applies to your sale, and to which parts of the gain, is a question for your tax adviser; the point is that a failed or partial exchange is not always taxed in the year of the sale.

Replacement property sells out inside the window

A Delaware statutory trust is the replacement many sellers identify when they cannot find a property of their own in 45 days (the structure qualifies under Rev. Rul. 2004-86; what DSTs charge is in our analysis of 90 DST Form Ds from 2026). Every DST files a Form D with the SEC, and many amend it as interests sell, so the filings show how fast supply goes.

We read every Form D and D/A filed from July 1 to October 5, 2026 by an issuer whose name contains “DST” or “Delaware Statutory Trust” (EDGAR quarterly form indexes, minus one fund that is not a trust): 129 filings from 76 DSTs. At each one's latest filing they list $5.25 billion of interests, $2.68 billion sold and $2.57 billion remaining (our sums). Eight were fully sold, 26 reported no sales yet (they list $1.57 billion between them) and ten were open but at least 90% sold. The median minimum investment is $100,000. Twelve DSTs from the exchange programs of large non-traded REIT managers (Ares, Blue Owl, JLL, Invesco, Apollo, Brookfield and Fortress, named in the filings) account for $2.52 billion, 47.9% of the amount offered; how those programs later fold DST owners into the REIT is in our 721 exchange guide.

Days between filings are our arithmetic. The largest new supply in the window is ADREX Diversified 12 DST, an Ares offering of $537.9 million with a $500,000 minimum and no sales reported at its August 31 filing. Form D amounts are what each sponsor reported at a point in time, and some sponsors amend more often than others, so a DST shown with capacity may already be closed: confirm availability with the sponsor before you write its name on an identification. Sponsor-level detail is in our Form D readings of Inland Private Capital and Kingsbarn.

What a seller can do with this

• Find your column first. If the property is titled to an LLC that files a partnership return, use the partnership column; your personal return is not the one that counts.
• If you close on or after October 18, 2026 (or September 17 for a partnership), plan the extension of the 2026 return when you sign the exchange agreement, and pay estimated 2026 tax by April 15, 2027 anyway.
• Put day 45 on the calendar the day you close, and note whether it lands on Thanksgiving, Christmas Day or New Year's Day. Send the identification on an earlier business day.
• Use all three slots. With DSTs selling tens of millions of dollars a month, identify backups; the 3-property rule costs nothing.
• Ask your intermediary when the cash would come back if you identify nothing, and in which tax year that falls.

FAQ

Sources, read and saved on October 5, 2026: 26 CFR 1.1031(k)-1, 1.6081-2 and 1.6081-4 as published on the eCFR (text as of September 30, 2026); 26 U.S.C. 1031, 6072 and 6081; IRS Instructions for Form 8824 (2025); IRS Publication 544; Rev. Proc. 2018-58 (Internal Revenue Bulletin 2018-50); and 129 Form D and D/A filings made with the SEC from July 1 to October 5, 2026 by issuers named as Delaware statutory trusts, found through the EDGAR quarterly form indexes, each with its accession number in the CSV. Dates, day counts, sums and percentages are our arithmetic. Form D amounts are as reported by each issuer on the filing date and may be estimates. This is analysis of public documents, not investment, legal or tax advice.