Selling a U.S. Partnership Interest as a Nonresident: Separate the Sale Date and Asset Records

When a nonresident alien or foreign corporation sells an interest in a U.S. partnership, tax liability does not turn on a single gross payment figure. Instead, federal tax law requires a strict separation between the sale date, the seller's tax residency, the partnership's underlying asset inventory, and the specific statutory rules governing tax sourcing and withholding. Under current post-2017 federal law, gain recognized by a foreign partner on the sale of a U.S. partnership interest is treated as effectively connected income (ECI) to the extent the partner would have been allocated ECI if the partnership had sold all of its assets at fair market value on the date of the transfer. To evaluate tax exposure and compliance obligations accurately, sellers and buyers must examine statutory sourcing rules alongside transferee withholding requirements under Internal Revenue Code Section 1446(f).

Direct Answer: How Nonresident Partnership Sales Are Taxed and Withheld

For dispositions occurring on or after November 27, 2017, Internal Revenue Code Section 864(c)(8) governs the sourcing and taxability of gain realized by nonresident aliens and foreign corporations selling U.S. partnership interests. If the partnership conducts a trade or business within the United States, gain or loss on the transfer is treated as effectively connected with that U.S. trade or business up to the partner's distributive share of gain or loss from a hypothetical fair-market-value sale of all partnership assets as of the transaction date. This rule treats only the supported portion as effectively connected; any remaining gain is not automatically ECI under §864(c)(8).

To enforce collection, Internal Revenue Code Section 1446(f)(1)—enacted under the Tax Cuts and Jobs Act of 2017 for transfers on or after January 1, 2018—requires the transferee (buyer) to deduct and withhold a 10% tax on the amount realized on the disposition, unless a specific statutory or regulatory exception applies. It is critical to distinguish Section 1446(f) transferee withholding from Section 1446(a) partnership withholding. Section 1446(a) requires the partnership itself to withhold tax on annual effectively connected taxable income (ECTI) allocated to foreign partners at the highest applicable individual or corporate tax rate. In contrast, Section 1446(f) imposes a 10% withholding obligation on the gross amount realized by the seller at the time of disposition, not on net gain or final tax liability.

Decision Branches: Sourcing vs. Withholding Rules Across Sale Eras

Determining the tax obligations of a foreign partner requires identifying the exact date of sale and matching the transaction to the correct statutory framework:

• Income-Tax Rule for Sales On or After November 27, 2017: IRC Section 864(c)(8) applies. Gain is treated as ECI based on a hypothetical asset sale by the partnership on the transfer date. The buyer’s withholding obligation must be assessed separately under §1446(f), whose statutory transfer effective date begins January 1, 2018, with later regulatory implementation dates.
• Sales Prior to November 27, 2017 (Historical Law): No statutory provision specifically sourced income from partnership interest dispositions. As established in Rawat v. Commissioner, Section 751(a) recharacterized gain attributable to inventory as ordinary income but did not deem an actual sale of inventory to convert foreign-source personal property gain into U.S.-source income.
• Transferee Withholding Obligations (Post-2017): The buyer must withhold 10% of the total amount realized under Section 1446(f)(1) using Form 8288 and Form 8288-A within statutory deadlines, unless the seller qualifies for an exception under Treasury Regulations Sections 1.1446(f)-1 through 1.1446(f)-5.
• Partnership Secondary Liability: If the transferee fails to withhold the required 10% under Section 1446(f)(1), IRC Section 1446(f)(4) directs the partnership to deduct and withhold that amount (plus interest) from future distributions otherwise payable to the transferee.

Realistic Hypothetical: Nonresident Sale of an Operating LLC Interest

To understand how these rules operate in practice, consider the following explicitly labeled hypothetical scenario:

Realistic Hypothetical: In June 2025, Elena, a foreign citizen and nonresident alien residing in Spain, agrees to sell her 20% membership interest in a Delaware LLC (classified as a partnership for federal tax purposes) to a domestic investor for $2.0 million in cash. The LLC operates a manufacturing business in Ohio. On the closing date, the LLC holds $500,000 in inventory, $1.5 million in equipment, and operational goodwill. The LLC provides a certified calculation showing that if all LLC assets were sold at fair market value on the closing date, Elena's allocable share of effectively connected gain would be $300,000.

Assume Elena’s total recognized gain is at least $300,000, the $2 million is the entire amount realized including any relevant liabilities, and no other coordination rule changes the calculation. Under IRC Section 864(c)(8), $300,000 of Elena's total realized gain is treated as ECI subject to U.S. federal income tax. Under IRC Section 1446(f)(1), the buyer is obligated to withhold 10% of the gross amount realized ($200,000: 10% × $2,000,000) and remit it to the Internal Revenue Service using Forms 8288 and 8288-A, unless an exception or reduced withholding certificate applies. Elena must file a U.S. nonresident income tax return (Form 1040-NR) for the tax year, compute her actual tax liability on the $300,000 ECI gain, and claim a tax credit for the $200,000 withheld by the buyer. The withholding amount does not fix her final tax liability; it serves as an advance tax collection mechanism.

Useful Evidence Task: Assembling the Tax Record Pack

Taxpayers and legal counsel preparing for or reviewing a partnership interest sale must organize a comprehensive record pack before closing. The essential evidence pack includes:

• Purchase and Sale Agreement: The executed contract setting the effective closing date, gross purchase price, liabilities assumed, and payment terms.
• Partnership Financial and Valuation Records: Balance sheets, inventory schedules, and asset appraisals establishing asset fair market values on the exact date of sale.
• Hypothetical Asset-Sale Calculation: A written schedule from the partnership allocating potential ECI gain or loss under Section 864(c)(8)(B) as of the transaction date.
• Residency and Entity Certification: Documentation verifying the seller's foreign tax residency, Form W-8BEN or W-8BEN-E, and historical U.S. tax return filings.
• Withholding Documentation: Copies of Form 8288, Form 8288-A, applicable Section 1446(f) non-foreign/exception certificates.
• Basis and Capital Account Schedules: Historical Schedule K-1 forms, capital account reconciliations, and seller basis calculations.

Match the withholding route to the actual transaction

The IRS partnership withholding guide distinguishes annual partnership-income withholding from transfer withholding and explains that different rules apply to publicly traded partnership interests. Its regulatory implementation dates are separate from the statutes’ enactment dates. Do not select a form or exception simply from the phrase partnership sale.

Before closing, counsel and the tax preparer should resolve the seller’s U.S. tax status, the amount realized including relevant liabilities, the asset-sale calculation, any real-property coordination, and the documentation needed for an exception or reduction. A capital account is not a substitute for a tax-basis calculation. Keep the computation and supporting certificates with the closing file.

Read our analysis of Rawat and its 2008 transaction for the historical source question. Contact our tax legal services practice about a present transaction’s records.

Current law: 26 U.S.C. §864(c)(8) and §1446(f). The IRS partnership withholding guide explains the separate withholding regimes.