What Foreign Investors Owe in U.S. Capital Gains Tax

Who Qualifies as a Non-Resident Alien for U.S. Tax Purposes

Non-resident capital gains tax treatment in the U.S. turns almost entirely on one threshold question: does the IRS classify you as a non-resident alien (NRA)? The answer determines which assets get taxed, at what rate, and through what withholding mechanism.

Under IRS Publication 519, you are an NRA if you are not a U.S. citizen, do not hold a green card, and fail the substantial presence test. That test requires physical presence of at least 31 days in the current year and 183 days over a weighted three-year period (counting all days in the current year, one-third of days in the prior year, and one-sixth of days two years back).

Passing that test makes you a U.S. resident for tax purposes, full stop. Failing it keeps you in NRA status, which triggers an entirely different tax regime.

One wrinkle worth flagging early: NRA status does not automatically mean you owe zero U.S. capital gains tax. The asset type matters enormously. U.S. real estate, publicly traded stock, partnership interests, and personal property each carry different treatment. The standard retail-investor summary ("foreigners don't pay U.S. capital gains tax") is accurate for stock portfolios and dangerously wrong for real estate.

U.S. Capital Gains Tax Treatment by Asset Type for Non-Resident Aliens

The most consequential thing an NRA investor can understand is that the U.S. does not apply a single capital gains regime to all assets. The table below summarizes the actual treatment across the asset classes most relevant to $5M+ investors.

The practical implication: a foreign investor holding a $10M U.S. stock portfolio and a $5M U.S. apartment building faces two entirely different tax problems when liquidating. The stock sale is likely tax-free. The property sale triggers mandatory withholding of $750,000 at closing, regardless of actual gain.

Do Non-Resident Aliens Pay Capital Gains Tax on U.S. Stock Sales?

Generally, no. IRS Publication 519 confirms that NRAs are not subject to U.S. capital gains tax on the sale of publicly traded U.S. securities, provided the gains are not effectively connected with a U.S. trade or business. This is one of the genuine structural advantages of NRA status over U.S. resident status.

The exception that catches high-net-worth investors off guard sits in IRC Section 871(a)(2). If an NRA is physically present in the U.S. for 183 or more days in the tax year, net U.S.-source capital gains become subject to a flat 30% tax. This 183-day rule is separate from the substantial presence test used to determine residency. You can fail the substantial presence test (and remain an NRA) while still triggering this 30% rate on stock gains simply by spending enough time in the country.

For FATFIRE individuals with multiple residences who actively manage their portfolios from wherever they happen to be, this is a real exposure. Spending a northern hemisphere summer in New York or a winter in Miami while executing a large portfolio rebalance could push you over 183 days and generate a material tax liability that would not have existed if the same trades were executed from London or Singapore.

The fix is straightforward but requires advance planning: track U.S. presence days carefully, and if you are approaching the threshold, consider whether large realizations can be timed to a year with fewer U.S. days. Your tax attorney should be modeling this annually, not reactively.

For strategies to minimize capital gains on stocks within a broader portfolio context, the 183-day rule is the first variable to address.

What Is FIRPTA and How Does It Affect Foreign Investors Selling U.S. Real Estate?

FIRPTA (the Foreign Investment in Real Property Tax Act) is the single most important piece of U.S. tax law for NRAs holding real estate. It requires the buyer in any transaction involving a U.S. real property interest sold by a foreign person to withhold a percentage of the gross sales price and remit it to the IRS.

The critical word is gross. The IRS requires withholding on the full sales price, not on the gain.

Under IRC Section 1445, the current withholding rates are:

The buyer (or closing agent) must file Form 8288 and Form 8288-A and remit the withholding within 20 days of closing, per IRS instructions for Form 8288.

Here is the liquidity math that matters for large transactions. A Canadian investor sells a $5M Manhattan apartment with an adjusted cost basis of $3.5M. Actual gain: $1.5M. Estimated federal tax at 20% long-term rate: $300,000. FIRPTA withholding at 15%: $750,000. The IRS holds $450,000 more than the investor's actual tax liability until a return is filed and a refund processed, which typically takes six to twelve months.

For investors transacting at this scale, the solution is to file Form 8288-B (Application for Withholding Certificate) before or at closing. A withholding certificate, if approved by the IRS, reduces withholding to the amount of the actual tax owed rather than 15% of gross proceeds. The IRS targets a 90-day processing window, though complex transactions often take longer. Filing early is essential.

The capital gains implications for non-primary residences add another layer here, particularly for investors holding multiple U.S. properties with different use histories.

How Much Is Withheld from a Non-Resident Alien Selling U.S. Property?

The short answer: 15% of whatever you receive at closing, with limited exceptions. But the structure of that withholding, and the options for reducing it, deserve more precision.

The withholding obligation falls on the buyer, not the seller. The buyer becomes personally liable to the IRS if they fail to withhold correctly. This creates practical pressure at closing: buyers and their attorneys are highly motivated to withhold, and sellers who want reduced withholding must have a certificate in hand before the transaction closes.

Three scenarios where withholding is reduced or eliminated:

Withholding certificate (Form 8288-B). The foreign seller applies to the IRS before closing, demonstrating that the actual tax liability is lower than 15% of gross proceeds. The IRS issues a certificate specifying the correct withholding amount. This is the primary tool for high-value transactions where the gain-to-price ratio is low.

Buyer's residence exemption. If the buyer acquires the property for use as a personal residence and the sales price is under $300,000, no withholding is required. At $300,000–$1,000,000, withholding drops to 10%. Above $1,000,000, the full 15% applies regardless of buyer intent.

Non-foreign affidavit. If the seller is not actually a foreign person, they can provide a certification of non-foreign status to the buyer, eliminating the withholding obligation. This is straightforward for individual sellers but requires careful analysis for entities.

For interstate real estate transactions and tax liability, state-level withholding requirements may stack on top of FIRPTA, particularly in California and New York. Budget for both.

What Is Effectively Connected Income and How Is It Taxed for Non-Residents?

Effectively Connected Income (ECI) is income that the IRS treats as connected with the conduct of a U.S. trade or business. According to the IRS, ECI is taxed at the same graduated rates that apply to U.S. citizens and residents (up to 37% for ordinary income), rather than the flat 30% FDAP withholding rate that applies to passive U.S.-source income.

The ECI distinction matters most in two scenarios common among high-net-worth foreign investors.

Active real estate operations. An NRA who owns a U.S. apartment building and makes an election under IRC Section 871(d) to treat rental income as ECI gains the ability to deduct expenses against that income (mortgage interest, depreciation, operating costs). Without the election, gross rental income is subject to 30% withholding. For a property generating $500,000 in gross rents with $350,000 in deductible expenses, the election can reduce taxable income from $500,000 to $150,000. The trade-off is that the investor is now engaged in a U.S. trade or business, which has other implications.

Partnership interests. An NRA holding an interest in a U.S. partnership that conducts a trade or business will generally have their distributive share of partnership income treated as ECI. On the sale of the partnership interest, the gain attributable to ECI assets is taxed at graduated rates, not the standard NRA exemption. The Tax Cuts and Jobs Act codified this treatment in IRC Section 864(c)(8), eliminating a planning strategy that had been used to avoid ECI characterization on partnership exits.

The line between passive investment (not ECI) and active business (ECI) is not always obvious. A foreign investor who owns a single U.S. rental property managed by a third party is generally not engaged in a U.S. trade or business. An investor who owns ten properties, employs staff, and makes day-to-day management decisions may be. The facts and circumstances test here has real stakes.

Which U.S. Tax Treaties Reduce Capital Gains Tax for Foreign Investors?

The U.S. maintains income tax treaties with more than 60 countries, and those treaties can meaningfully reduce withholding rates on dividends, interest, and certain other income. The IRS maintains a full list at its United States Income Tax Treaties page.

What treaties generally do not do: eliminate FIRPTA withholding on real estate. This is the most common misconception among foreign investors from treaty countries. A UK investor selling U.S. real estate still faces 15% FIRPTA withholding at closing. The treaty may reduce the ultimate tax liability, but the withholding still occurs. The investor claims treaty benefits on a subsequently filed Form 1040-NR and receives a refund of any excess withholding. That distinction requires proactive cash flow planning on large transactions.

To claim treaty benefits, NRAs must file Form W-8BEN with the relevant withholding agent, per IRS Publication 515.

For investors from countries with no capital gains tax at the domestic level, the U.S. tax exposure on real estate can come as a significant surprise, particularly given that FIRPTA withholding is based on gross proceeds rather than gain.

Can a Foreign Investor Use an LLC to Reduce U.S. Capital Gains Tax Exposure?

Entity structuring is where the planning gets interesting, and where generic advice becomes genuinely dangerous.

The most commonly discussed structure is holding U.S. real estate through a foreign corporation. The appeal is intuitive: FIRPTA withholding applies to dispositions of U.S. real property interests, and if a foreign corporation holds the property, the buyer acquires corporate shares rather than real property directly. No FIRPTA withholding at the property level.

The IRS anticipated this. Under IRC Section 897, a foreign corporation that holds U.S. real property becomes a U.S. Real Property Holding Company (USRPHC). Shares in a USRPHC are themselves treated as U.S. real property interests, so FIRPTA applies to the share sale. The structure delays but does not eliminate the exposure.

There is a further problem. When a foreign corporation repatriates earnings from U.S. operations, IRC Section 884 imposes a branch profits tax of up to 30% on the after-tax earnings deemed to have been removed from the U.S. This is in addition to the corporate-level tax on income. For investors who were advised to use a foreign corporation primarily to avoid FIRPTA, the branch profits tax is often an unpleasant discovery.

Domestic LLCs treated as disregarded entities or partnerships offer different trade-offs. A single-member LLC owned by an NRA is transparent for U.S. tax purposes, meaning the NRA is taxed directly on the LLC's income and gains. FIRPTA still applies to real property sales. The LLC does not change the fundamental tax treatment but can provide liability protection and operational flexibility.

Multi-member LLCs and limited partnerships can be structured to accommodate multiple foreign investors, with careful attention to ECI characterization and withholding obligations on distributions. For capital gains tax on foreign property investments, the entity structure at the foreign level also matters and should be analyzed alongside the U.S. structure.

The honest answer is that no entity structure eliminates U.S. capital gains tax on real estate for foreign investors. The structures that appear to do so typically shift the tax event rather than remove it, and often introduce new exposures in the process.

How NRA Status Affects Estate Planning and Step-Up in Basis for U.S. Assets

This is where the stakes for $5M+ investors become most acute, and where the gap between NRA treatment and U.S. citizen treatment is most severe.

Under IRC Section 2101, NRAs are subject to U.S. estate tax on U.S.-situs assets. That includes U.S. real estate, shares in U.S. corporations, and certain other assets physically located in the U.S. The estate tax rate reaches 40% above the exemption threshold. For U.S. citizens and domiciliaries in 2024, the unified credit shelters $13.61 million from estate tax. For NRAs, the IRS provides a unified credit equivalent of only $60,000.

A foreign investor who dies holding $5M in U.S. real estate faces estate tax on roughly $4.94M of that value. At 40%, that is approximately $1.98M in estate tax. The same investor, if a U.S. citizen, would owe nothing under current law.

The step-up in basis rules do apply to NRAs. Assets included in an NRA's estate receive a stepped-up cost basis to fair market value at death, which eliminates embedded capital gains for the heirs. This is one of the few areas where NRA treatment mirrors U.S. citizen treatment.

The planning implication: for NRAs holding appreciated U.S. real estate, dying with the asset (and getting the step-up) may be preferable to selling it during life (and paying FIRPTA plus capital gains tax). This is not a strategy so much as an observation that the hold-versus-sell decision has an estate planning dimension that pure capital gains analysis misses.

Structures that can reduce U.S. estate tax exposure for NRAs include holding real estate through foreign corporations (which converts U.S.-situs real property into foreign corporate shares, which are not U.S.-situs assets for estate tax purposes) and certain trust structures. Each has trade-offs, as discussed above.

For a full picture of US inheritance tax obligations for non-residents, the interaction between estate tax, step-up in basis, and FIRPTA on post-death sales requires coordinated planning across estate and income tax counsel.

Smart Strategies for Managing Non-Resident Capital Gains Tax

The most effective planning happens before a transaction, not during it. A few specific approaches worth evaluating:

1031 exchanges. NRAs can defer capital gains on U.S. real estate sales by reinvesting proceeds into like-kind U.S. real property under IRC Section 1031. FIRPTA withholding still applies at closing unless a withholding certificate is obtained, but the gain itself is deferred. The replacement property must be identified within 45 days and acquired within 180 days. For investors managing a U.S. real estate portfolio, 1031 exchanges are the primary deferral mechanism. The capital gains tax on vacation homes analysis changes materially if the property qualifies for 1031 treatment.

Installment sales. Spreading gain recognition over multiple years through an installment sale under IRC Section 453 can reduce the effective tax rate and improve cash flow. FIRPTA withholding on installment sales requires specific handling, and the IRS has rules governing how withholding is applied to each payment.

Loss harvesting. NRAs with ECI from multiple U.S. sources can offset gains with losses within the same ECI basket. The wash-sale rule applies: repurchasing the same or substantially identical security within 30 days before or after a sale disallows the loss.

Timing around the 183-day rule. For NRAs with large stock portfolios, managing U.S. presence days is a legitimate planning tool. Executing significant realizations in years with fewer U.S. days avoids the IRC Section 871(a)(2) 30% tax on net gains.

Pre-immigration planning. NRAs who are considering becoming U.S. residents or citizens should consider realizing appreciated positions before establishing U.S. tax residency. Once you cross into resident status, U.S. capital gains tax applies globally. The window before that transition is a planning opportunity that closes permanently.

For investors also evaluating California's taxation of out-of-state gains, note that California does not conform to federal NRA exemptions in all respects and applies its own withholding requirements on real property sales.

Reporting and Compliance Requirements for Non-Resident Alien Investors

The filing obligations for NRAs with U.S. investments are specific and the penalties for non-compliance are not trivial.

Form 1040-NR. NRAs with U.S.-source income, including capital gains treated as ECI, must file Form 1040-NR. The deadline is generally June 15 for NRAs not subject to withholding, with an extension available to October 15. NRAs who had U.S. wages subject to withholding face the standard April 15 deadline.

Form 8288 and 8288-A. The buyer or closing agent files these forms to report and remit FIRPTA withholding within 20 days of closing. The seller receives a copy of Form 8288-A, which they attach to their 1040-NR to claim credit for the withholding.

Form 8288-B. The foreign seller files this form to request a withholding certificate before closing. Filing early is critical: the IRS targets 90 days to process, and the certificate must be in hand at closing for withholding to be reduced.

Form 8949 and Schedule D. Capital gains and losses are reported on Form 8949 and summarized on Schedule D, attached to the 1040-NR.

Form W-8BEN. NRAs file this form with withholding agents (brokers, banks, paying agents) to certify their foreign status and claim applicable treaty benefits. It must be updated every three years or when circumstances change.

Penalties for failure to file or failure to withhold under FIRPTA can reach 100% of the required withholding amount in egregious cases. The IRS has increased enforcement focus on FIRPTA compliance, particularly for high-value transactions.

The practical recommendation: retain a tax attorney with specific international tax experience before any significant U.S. transaction, not after. The cost of a withholding certificate application or pre-transaction structure review is a rounding error against the potential cost of getting it wrong on a $5M+ deal.

References

• Internal Revenue Service -- "Publication 519: U.S. Tax Guide for Aliens" (2024).
• Internal Revenue Service -- "Foreign Investment in Real Property Tax Act (FIRPTA) Withholding -- IRC Section 1445" (2024).
• Internal Revenue Service -- "Instructions for Form 8288: U.S. Withholding Tax Return for Certain Dispositions by Foreign Persons" (2024).
• Internal Revenue Service -- "IRC Section 871 -- Tax on Nonresident Alien Individuals" (via Cornell Legal Information Institute).
• Internal Revenue Service -- "United States Income Tax Treaties -- A to Z" (2024).
• Internal Revenue Service -- "Publication 515: Withholding of Tax on Nonresident Aliens and Foreign Entities" (2024).
• Internal Revenue Service -- "Effectively Connected Income (ECI) -- International Taxpayers" (2024).
• Internal Revenue Service -- "Estate Tax for Nonresident Aliens -- IRC Section 2101".