What is the two-year rule for related-party 1031 exchanges?

The clock binds both sides and starts at the last transfer, not at the first

Section 1031(f)(1) hangs the disallowance on two triggers: "the related person disposes of such property," or "the taxpayer disposes of the property received in the exchange from the related person which was of like kind to the property transferred." Either one is enough, and your counterparty's decision is outside your control.

Publication 544 fixes the start: the two-year holding period begins on the date of the last transfer of property that was part of the like-kind exchange. In a deferred structure that is usually the day the final replacement deed is recorded, so a swap opened in one year can run its clock from the next.

Hypothetically, if the last transfer records on 14 March 2027 the period closes on 14 March 2029, and a contract signed on 1 March 2029 that closes in April sits on the wrong side of the line depending on when title actually moves.

The bill arrives in the year of the sale, and it arrives for both parties

The closing clause of section 1031(f)(1) says any gain or loss recognised by reason of the subsection "shall be taken into account as of the date on which the disposition referred to in subparagraph (C) occurs." Nobody amends the exchange-year return.

Publication 544 carries a worked example with siblings. In a December 2024 swap the taxpayer pays $15,000 of cash and realises $135,000 of gain; the sister realises $145,000 and recognises $15,000 in 2024. When the taxpayer sells to a third party in 2025, the 2024 exchange is disqualified: $135,000 goes on the taxpayer's 2025 return alongside the 2025 sale, and the sister reports the remaining $130,000 on her own 2025 return, lifting her basis to $200,000.

That is the part families underestimate. One person's decision to sell reaches into the other's tax year, which is why the two-year commitment belongs in the exchange agreement rather than in a conversation.

Three exceptions, and only three, with conditions attached to each

Section 1031(f)(2) removes a disposition from the test in exactly three situations, mirrored by the check boxes on Form 8824 line 11.

The second one is order-sensitive, and the third one carries the burden of proof. Read them against the facts you have, not the facts you would like.

• Section 1031(f)(2)(A): a disposition after the earlier of the death of the taxpayer or the death of the related person.
• Section 1031(f)(2)(B): a compulsory or involuntary conversion within the meaning of section 1033, but only if the exchange occurred before the threat or imminence of that conversion.
• Section 1031(f)(2)(C): a disposition for which it is established to the satisfaction of the Secretary that neither the exchange nor the disposition had tax avoidance as one of its principal purposes.
• The Form 8824 instructions say tax avoidance is generally not a principal purpose for a disposition in a nonrecognition transaction, an exchange where the related parties derive no advantage from shifting basis, or an exchange of undivided interests that leaves each party owning a whole property or a larger undivided share.

What stops the clock: section 1031(g) and a substantially diminished risk of loss

Section 1031(g) suspends the running of the two-year period for any period during which the holder's risk of loss on the property is substantially diminished. It names three ways that happens: the holding of a put on the property, the holding by another person of a right to acquire it, and a short sale or any other transaction.

Publication 544 repeats the rule and adds that such a period is simply not counted toward the two years. An option granted to a buyer a year after the swap therefore does not end the exposure; it extends it.

The practical reading is that a family which papers a future buy-out at the same time as the exchange has not shortened the period at all. It has arguably created the evidence of a pre-arranged cash exit that section 1031(f)(4) is written to catch.

On the return: line 7, Part II, and two more filings

The Instructions for Form 8824 require the form to be filed for the two years following the year of a related-party exchange. Line 8 collects the related party's name, relationship and identifying number; lines 9 and 10 ask whether either of you disposed of the like-kind property during the year and before the two-year date.

If both answers are "No" and it is not the exchange year, you stop there. If either is "Yes" and no line 11 exception applies, you complete Part III and carry the deferred gain or loss from line 24 onto that year's return, taxed as a straightforward sale.

Checking box 11c means attaching an explanation. How to fill out Form 8824 covers the rest of the schedule, and 1031 audit risk and the records to keep covers the file that supports an 11c attachment years later.

Why the qualified-intermediary versions of this question have different answers

The two-year rule in 1031(f)(1) is triggered by exchanging property with a related person. Where a qualified intermediary sits in the middle and your replacement comes from an unrelated seller, you did not exchange with your relative, and the analysis moves to section 1031(f)(4), which asks whether the deal was structured to avoid the subsection's purposes.

That is why selling to a family member is usually workable while buying from a relative usually is not, even though both involve the same people and the same two-year concept.

Before you sign a swap agreement, have your CPA or attorney confirm who is related under the section 267(b) and 707(b)(1) lists and write the two-year commitment into the documents on both sides.