The Section 721(c) gain deferral method lets a U.S. person contribute appreciated property to a partnership that has related foreign partners without recognizing the built-in gain immediately, so long as the partnership adopts specific allocation rules, the U.S. transferor consents to an extended assessment period, and the partnership meets ongoing reporting requirements every year the deferral is in effect. Skip any of those pieces and the deferral collapses: gain becomes taxable now, and penalties can follow.
The trade is straightforward in concept. You keep the tax bill off this year’s return; in exchange, you take on years of detailed compliance, and a single misstep can undo the whole arrangement.
When Section 721(c) Applies
Contributing property to a partnership for a partnership interest is normally tax-free under Section 721(a).1Office of the Law Revision Counsel. 26 U.S.C. 721 – Nonrecognition of Gain or Loss on Contribution Section 721(c) is the carve-out: Treasury regulations deny nonrecognition when built-in gain could end up in the income of someone other than a U.S. person. The override applies only when three things line up at the same time.
A Section 721(c) Partnership
The partnership can be domestic or foreign. Immediately after the contribution and any related transactions, a related foreign person must be a direct or indirect partner, and the U.S. transferor together with related persons must own 80 percent or more of the interests in capital, profits, deductions, or losses.2eCFR. 26 CFR 1.721(c)-1 – Overview, Definitions, and Rules of General Application Relatedness is tested under Sections 267(b) and 707(b)(1), which generally treat parties as related where one owns more than 50 percent of the other or where family members or affiliated entities control both sides.3Office of the Law Revision Counsel. 26 U.S.C. 267 – Losses, Expenses, and Interest With Respect to Transactions Between Related Taxpayers A related foreign person is any related person who is not a U.S. person and is not itself a partnership.4eCFR. 26 CFR 1.721(c)-1 – Overview, Definitions, and Rules of General Application
Section 721(c) Property
The property has to carry built-in gain, meaning fair market value exceeds adjusted tax basis at the moment of contribution. Several categories of “excluded property” fall outside the rules altogether:5Federal Register. Transfers of Certain Property by U.S. Persons to Partnerships With Related Foreign Partners
- Cash equivalents.
- Securities within the meaning of Section 475(c)(2).
- Tangible property with built-in gain of $20,000 or less.
- Partnership interests where 90 percent or more of the underlying property by value falls into the three categories above.
The exclusions keep the focus on the contributions most likely to shift meaningful gain offshore: intellectual property, real estate, high-value equipment.
The $1 Million De Minimis Threshold
Even non-excluded property gets a pass if the total built-in gain across all Section 721(c) property contributed to the same partnership in a taxable year is $1 million or less.6eCFR. 26 CFR 1.721(c)-2 – Recognition of Gain on Certain Contributions of Property to Partnerships With Related Foreign Partners Contributions during the year are aggregated, so splitting one large asset into several smaller pieces will not sidestep the threshold.
How the Deferral Works
When Section 721(c) is triggered, the default is immediate gain recognition. The gain deferral method preserves nonrecognition, but only when all five conditions in the regulations are met.7eCFR. 26 CFR 1.721(c)-3 – Gain Deferral Method
The Remedial and Consistent Allocation Path
The most common route requires the partnership to adopt the remedial allocation method under Treasury Regulation § 1.704-3(d) for the contributed property. That method creates notional tax items to bridge the difference between the property’s book value and its tax basis, so the U.S. transferor is allocated the right share of taxable income and gain over the asset’s life.
Alongside that, the partnership must follow the consistent allocation method. Within any single taxable year, every book item of income, gain, deduction, and loss tied to the Section 721(c) property must be allocated to the U.S. transferor in the same percentage. The percentage can shift from year to year, but it cannot shift among book items within a year. This stops a partnership from, say, sending more depreciation to the U.S. transferor while routing less income the same way.
The ECI Alternative
If every related foreign partner will pay U.S. tax on its share of the property’s income and gain as effectively connected income under Section 871 or 882, and neither the partnership nor any related foreign partner claims treaty benefits that would exempt or reduce that tax, the partnership does not have to use the remedial or consistent allocation methods.7eCFR. 26 CFR 1.721(c)-3 – Gain Deferral Method The rationale: if foreign partners already owe U.S. tax on their share, there is no gain to shift.
Consent, Extension, and Reporting Conditions
Under either path, the U.S. transferor must agree to recognize any remaining built-in gain if an acceleration event happens, and must consent to extend the IRS’s assessment period. That consent is given on Form 8838-P, which extends the assessment period to 96 months (eight years) after the close of the taxable year that includes the contribution.8Internal Revenue Service. Form 8838-P – Consent To Extend the Time To Assess Tax Under Section 721(c) The procedural and reporting requirements of Treasury Regulation § 1.721(c)-6 must then be met for every year the deferral is in effect.
The partnership cannot change its allocation methods for the contributed property while the deferral runs. A switch away from remedial allocation, or an inconsistency in how book items reach the U.S. transferor, can itself be treated as an acceleration event.
Annual Reporting
The reporting workload is real and it does not stop after year one. It begins with the contribution year and repeats every year the deferral applies.
Forms and Filings
Schedule G of Form 8865 is the main reporting vehicle. The U.S. transferor uses it to identify the property, report the built-in gain, and show compliance with the gain deferral method.9Internal Revenue Service. Instructions for Form 8865 Schedule G must be filed in the year of contribution and in every subsequent year the deferral method applies, even where the original contribution predated 2018.
The U.S. transferor must also prepare and keep a Gain Deferral Agreement in permanent records. The agreement certifies that the transferor and the partnership will follow the regulatory requirements, identifies the property, and lists the names, taxpayer identification numbers, and ownership percentages of all partners, including the related foreign persons. Form 8838-P accompanies the filing.
Deadlines
All required schedules and statements attach to the U.S. transferor’s timely filed federal income tax return, including extensions. For individuals, the base deadline is April 15 with an automatic six-month extension to October 15.10Internal Revenue Service. When to File Calendar-year C corporations also file by April 15, with the same six-month extension available.11Internal Revenue Service. Publication 509 (2026), Tax Calendars Miss the deadline and the gain deferral method generally cannot be elected: the built-in gain becomes immediately taxable.
Successor Events and Ongoing Disclosures
Each annual return must include updated Schedule G information and disclose any successor events during the year, including a description, the date, and the identifying information for any successor partnership or corporation.12eCFR. 26 CFR 1.721(c)-6 – Procedural and Reporting Requirements The concept is simple, the execution is not: a missed annual filing can produce penalties and, in the wrong circumstances, act as an acceleration event.
What Ends the Deferral
An acceleration event is anything that would reduce the built-in gain the U.S. transferor would eventually recognize, or would push recognition further out. When one occurs, the deferral ends and tax is due on the remaining built-in gain in that year.13eCFR. 26 CFR 1.721(c)-4 – Acceleration Events
Common Triggers
The clearest trigger is the partnership selling or exchanging the contributed property. A disposition of the U.S. transferor’s partnership interest, whether by sale, gift, or indirect transfer such as an ownership change in a corporate partner, also counts. Contributing the Section 721(c) property to another partnership, or contributing an interest in the Section 721(c) partnership to another partnership, are acceleration events too. So is failing to comply with any condition of the method, including changing allocation methods or missing a reporting requirement.
Remaining built-in gain equals the original built-in gain reduced by any gain already allocated to the U.S. transferor through remedial allocations during the deferral. The taxpayer reports it as taxable income for the year of the event. Long-term capital gains rates of 0, 15, or 20 percent apply depending on income, and the 3.8 percent net investment income tax can apply on top of that.14Internal Revenue Service. Topic No. 409, Capital Gains and Losses15Internal Revenue Service. Topic No. 559, Net Investment Income Tax
Terminations and Successor Events
Not every event that looks like it should end the deferral forces gain recognition. The regulations identify two categories of exceptions.16eCFR. 26 CFR 1.721(c)-5 – Acceleration Event Exceptions
A termination event ends the gain deferral method without triggering gain. Examples include the partnership transferring the property (other than a partnership interest) to a domestic corporation in a Section 351 transaction; the partnership incorporating into a domestic corporation and liquidating as part of the transaction; the partnership distributing the property back to the U.S. transferor (or, in certain cases, a member of the transferor’s consolidated group); the partnership no longer having any direct or indirect related foreign partner, with no plan for one to rejoin; and a fully taxable sale of the property, or the U.S. transferor’s sale of its entire partnership interest in a fully taxable transaction.
A successor event also avoids acceleration, but the deferral continues with a new party stepping into the U.S. transferor’s shoes. If the U.S. transferor contributes its partnership interest to a domestic corporation in a Section 351 transaction, for instance, the corporation becomes the new U.S. transferor and takes on the compliance obligations.
Partial Acceleration
Some events trigger recognition of only part of the remaining built-in gain. If a partnership distribution produces a positive basis adjustment to the Section 721(c) property under Section 734, the U.S. transferor recognizes gain equal to that adjustment (reduced by any gain already recognized under Section 731(a)), capped at the remaining built-in gain.17GovInfo. 26 CFR 1.721(c)-5 – Acceleration Event Exceptions Certain regulatory allocations that deviate from what consistent allocation would require also trigger partial acceleration, with gain limited to the departing amount.
Voluntary Acceleration
A U.S. transferor can elect to treat an acceleration event as occurring at any time by recognizing the remaining built-in gain and meeting the reporting requirements. This deemed acceleration event can be useful when ending the compliance burden makes sense, or when recognizing gain in the current year fits broader planning.13eCFR. 26 CFR 1.721(c)-4 – Acceleration Events
Non-Willful Reporting Failures
One relief valve. A failure to comply with the procedural and reporting requirements does not trigger acceleration if it is not willful. An inadvertent missed filing is treated differently from a decision to stop complying. The relief does not wipe out late-filing penalties; it just prevents the deferral from collapsing over a paperwork error.18GovInfo. 26 CFR 1.721(c)-4 – Acceleration Events
Penalties for Non-Compliance
Two penalty regimes can apply, and they can stack.
Failing to timely file a complete Form 8865 carries an initial penalty of $10,000 per foreign partnership per tax year. If the IRS sends a notice and the information still isn’t provided within 90 days, an additional $10,000 accrues for each 30-day period the failure continues, up to $50,000 per failure.9Internal Revenue Service. Instructions for Form 8865 Total exposure for a single year of a single partnership can reach $60,000.
Section 6038B adds a separate penalty for failing to report the contribution itself: 10 percent of the fair market value of the contributed property at the time of transfer, capped at $100,000 unless the failure was due to intentional disregard, in which case the cap disappears. On top of the monetary penalty, the taxpayer must recognize gain as if the property had been sold at fair market value on the contribution date.19Office of the Law Revision Counsel. 26 U.S.C. 6038B – Notice of Certain Transfers to Foreign Persons For a $5 million contribution, that translates into a $100,000 penalty plus full gain recognition. A reasonable cause defense exists, but the IRS evaluates it case by case and the taxpayer bears the burden.
Tiered Partnerships
Layered structures do not offer a workaround. When a U.S. transferor is a partner in an upper-tier partnership that contributes property to a lower-tier partnership, the regulations look through the structure. The U.S. transferor is treated as contributing its proportionate share of the property to the lower-tier partnership for purposes of determining whether that lower-tier partnership is itself a Section 721(c) partnership.20eCFR. 26 CFR 1.721(c)-2 – Recognition of Gain on Certain Contributions of Property to Partnerships With Related Foreign Partners Where the gain deferral method applies in a tiered structure, the tiered-partnership rules in Treasury Regulation § 1.721(c)-3(d) must also be satisfied. The same allocation and reporting requirements follow the property down through each tier.