Introduction: Section 871(m) and the Non-US Spouse Who Trades American Shares
Section 871(m) quietly takes thirty per cent of the dividend income embedded in your British spouse's US-linked derivatives, and almost nobody tells her. She holds no American shares. She has never filed an American tax return. Nevertheless, the moment she opens a contract for difference over Apple, Coca-Cola or Verizon through a London broker, the Internal Revenue Service treats part of her profit as a United States dividend and taxes it at source.
Furthermore, this charge lands on a person who has no obvious way to recover it. Her American husband files jointly or separately, claims foreign tax credits and moves on. She, by contrast, sits outside that system entirely. Consequently, the withholding becomes a permanent leak rather than a timing difference, and it compounds every year the position stays open.
At TaxYork, we see this repeatedly among mixed-nationality households in London, Edinburgh and the Home Counties. One spouse is American and heavily advised. The other is British, holds the family's trading account, and receives no cross-border attention whatsoever. Meanwhile, the 2027 expansion of Section 871(m) is about to widen the net considerably.
Why Section 871(m) Exists at All
Congress wrote Section 871(m) to close a straightforward avoidance route. A non-US investor who bought Microsoft shares directly suffered thirty per cent withholding on the dividend. However, the same investor who bought a total return swap over Microsoft received an economically identical payment with no withholding whatsoever.
Therefore, the legislation deems certain derivative payments to be "dividend equivalents" and sources them to the United States. Additionally, the final Section 871(m) regulations at 26 CFR 1.871-15 set out precisely which contracts fall inside the perimeter. The rule is not aimed at ordinary investors. Nevertheless, it catches them without mercy.
What Counts as a Dividend Equivalent Payment Under Section 871(m)
A dividend equivalent is any payment under a derivative that references a US share and is directly or indirectly contingent on, or determined by reference to, a dividend paid by that company. Importantly, no actual dividend needs to change hands. An implicit adjustment inside the contract pricing is enough.
The Instruments Most Commonly Caught
Contracts for difference over single American shares sit squarely inside the rules. Spread bets over US equities do too, despite their gambling character under British law. Similarly, total return swaps, single-stock forwards, deep in-the-money options and many structured notes referencing American companies all qualify as potential Section 871(m) transactions.
Meanwhile, securities lending arrangements produce substitute dividends that have been within the withholding net for far longer. Consequently, a stock loan programme run by a British broker over an American holding can generate a US charge that never appears on any UK statement.
What Sits Outside the Perimeter
Direct ownership of US shares is outside this particular rule, though ordinary dividend withholding applies instead. Additionally, derivatives over non-US companies fall away entirely, even where those companies earn American revenue. Notably, derivatives referencing a qualified index escape as well, and that exception matters enormously in practice.
The Delta Test and the Phase-In That Ends in 2027
Section 871(m) measures exposure using delta, the ratio that expresses how far a derivative's value moves with the underlying share. A delta of 1.0 means the instrument tracks the share pound for pound. Investopedia's explanation of delta sets out the mechanics for readers unfamiliar with options pricing.
Currently, only delta-one transactions are caught. However, that limitation exists purely because the Treasury has deferred the wider rules five separate times. IRS Notice 2024-44 extended the phase-in through 2026, confirming that the substantial equivalence and lower delta provisions will not apply to any non-delta-one transaction issued before 1 January 2027.
What Changes on 1 January 2027
From that date, any newly issued derivative with a delta of 0.8 or higher enters the regime. Therefore, a covered call written against a US holding, a deep in-the-money call option, or a leveraged certificate over an American share can all become taxable events for your spouse. Positions issued before that date remain outside the expanded rules, which creates a genuine and time-limited planning window during the closing months of 2026.
Furthermore, the same notice extends the good faith enforcement standard to delta-one transactions throughout 2017 to 2026, and to non-delta-one transactions in 2027. Accordingly, brokers who get this wrong next year face a softer landing than the investors they failed to warn.
The Combined Transaction Trap Nobody Explains
Here is the point that virtually every published guide omits. Two separate contracts can be combined and tested together under the regulations. A bought call plus a written put over the same American share creates a synthetic long position with a delta approaching 1.0, even though neither leg alone would qualify.
Notice 2024-44 does give withholding agents a simplified standard through 2026, requiring them to combine only over-the-counter transactions priced, marketed or sold together. However, the notice states explicitly that this simplification applies only to withholding agents and does not apply to taxpayers who are the long party. Consequently, your spouse can carry a personal United States tax liability on a combined position where her broker deducted nothing at all.
The Qualified Index Exception and How to Use It
Derivatives referencing a qualified index produce no dividend equivalents for the life of the contract. Therefore, this exception is the single most valuable structural answer available to a British investor who wants American equity exposure without American withholding.
The Precise Criteria
An index qualifies where it references twenty-five or more component securities, where no single component exceeds fifteen per cent of the weighting, and where no five components together exceed forty per cent. Additionally, the index must be rebalanced only according to publicly stated, predefined criteria, and it must be traded through futures or option contracts on a regulated exchange.
Finally, the index must not have produced an annual dividend yield in the preceding calendar year greater than 1.5 times that of the S&P 500. Importantly, the test is applied on the first business day of each calendar year, so an index that qualifies today may not qualify next January.
The Practical Consequence
Broad market index derivatives generally escape. Narrow sector baskets, thematic indices and single-stock contracts generally do not. Consequently, restructuring a concentrated single-name derivative book into qualified index exposure removes the charge entirely, though it obviously changes the investment profile as well.
The Treaty Rate Almost Nobody Claims
Section 871(m) sources dividend equivalents to the United States and taxes them as dividends. Therefore, the US-UK double taxation treaty becomes directly relevant, because Article 10 caps American withholding on portfolio dividends paid to a UK resident at fifteen per cent rather than thirty.
However, the reduced rate is not automatic. Your spouse must file a valid Form W-8BEN with the broker, complete Part II, and specifically claim treaty benefits under the residence article. The IRS instructions for Form W-8BEN set out the certification requirements in detail.
In our experience, most British retail platforms default to the statutory thirty per cent and apply treaty relief only where the client has actively claimed it. Furthermore, a W-8BEN expires at the end of the third calendar year following signature. Consequently, we routinely find households paying double the correct rate simply because a five-year-old form was never renewed.
Why Section 871(m) Withholding Often Becomes a Permanent Cost
British investors assume that American tax deducted at source will be relieved somewhere. Unfortunately, that assumption fails more often than it succeeds in this particular corner of the code.
The Spread Betting Problem
The United Kingdom treats spread betting as gambling, and HMRC's guidance on betting and gambling confirms that winnings fall outside income tax and capital gains tax altogether. Therefore, a spread bet over an American share generates a US charge with no corresponding British liability.
The treaty relieves double taxation by giving credit against UK tax computed on the same income. Where there is no UK tax, there is no credit. Consequently, the entire deduction is a dead cost, and the position becomes materially less attractive than the headline spread suggests.
The Character Mismatch on Contracts for Difference
Contracts for difference are different but scarcely better. The United Kingdom taxes the net gain as a capital gain, while the United States charges an income withholding on the dividend element. Because the two charges fall on different measures with different characters, the credit rarely lines up cleanly.
Additionally, a loss-making CFD position still produces dividend equivalents. Therefore, your spouse can suffer American withholding in a year when her British computation shows a capital loss and no tax to relieve. Guidance from ICAEW on cross-border tax matters and from the Chartered Institute of Taxation both emphasise how frequently these mismatches strand relief.
Where the American Spouse Fits Into All of This
Section 871(m) applies only to non-resident aliens and foreign corporations. Therefore, it does not apply to your American spouse at all. That sounds like good news. In reality, it introduces a different set of problems.
Joint Accounts Change Everything
Where the trading account is held jointly, the broker will demand a Form W-9 from the American holder and will report accordingly. Furthermore, the American spouse then holds a financial interest in a foreign financial account, which triggers FBAR reporting to FinCEN once the aggregate balance exceeds ten thousand dollars at any point in the year.
Additionally, Form 8938 reporting under FATCA may follow, and the derivative contracts themselves count as specified foreign financial assets. Our FBAR and FATCA compliance service exists precisely because these accounts are so frequently missed.
The Section 6013(g) Election
Some households elect under section 6013(g) to treat the non-US spouse as a United States resident for income tax purposes. Consequently, Section 871(m) stops applying, because the spouse is no longer a non-resident alien and the thirty per cent withholding falls away.
However, the price is steep. Her worldwide income enters the American tax net permanently, the election binds until revoked, and it can only be made once in a lifetime. Therefore, we treat it as a considered structural decision rather than a quick fix for a withholding problem.
Reclaiming Over-Withheld Section 871(m) Tax From the IRS
Where thirty per cent was deducted and fifteen per cent was correct, the excess is recoverable. Nevertheless, the mechanism is slower and more restrictive than most clients expect.
The Form 1042-S and Form 1040-NR Route
The broker reports the withholding on Form 1042-S. Your spouse then files Form 1040-NR claiming the treaty rate and requesting a refund of the difference. Furthermore, she will need an Individual Taxpayer Identification Number if she does not already hold one.
Crucially, section 6511 limits refund claims to three years from the filing deadline or two years from payment, whichever expires later. Therefore, delay destroys the claim outright. Guidance for non-resident aliens on the IRS website sets out the wider filing framework, while MoneyHelper's guidance on tax abroad offers a general orientation for UK readers.
Case Study: A Mixed-Nationality Household in Kensington
James is an American citizen working in London. Eleanor, his British wife, holds no US status and runs the family's trading account in her sole name. She came to us in September 2026 after her husband's US tax return preparation raised questions about the household's wider position.
Eleanor held a deliberately income-oriented derivative book with a notional value of 2,400,000 dollars, split between contracts for difference of 1,600,000 dollars and spread bets of 800,000 dollars, all over single American shares yielding an average of 4.1 per cent. Consequently, her annual dividend equivalents amounted to 98,400 dollars.
Her broker withheld the full statutory thirty per cent, or 29,520 dollars each year. However, a valid treaty claim on Form W-8BEN would have reduced that to fifteen per cent, or 14,760 dollars. Therefore, she over-paid 14,760 dollars annually for four consecutive years, a total of 59,040 dollars.
The picture worsened on the spread betting side. Those positions produced 32,800 dollars of dividend equivalents and 9,840 dollars of American withholding each year. Because British law treats the winnings as gambling, Eleanor had no UK liability to credit the American tax against. Accordingly, that portion was a pure and irrecoverable cost.
We filed protective returns for the three years still open under section 6511 and recovered 44,280 dollars. Unfortunately, the earliest year had already closed, and 14,760 dollars was permanently lost. Meanwhile, we identified a synthetic long position built from a bought call and a written put over a fourth American share. Although the broker had withheld nothing on it, the combined delta approached 1.0, and Eleanor carried an unreported liability of 4,100 dollars that we disclosed and settled.
Finally, we restructured the concentrated single-name exposure into qualified index derivatives before the 1 January 2027 threshold, eliminating the charge prospectively.
Section 871(m) Planning Before the 2027 Threshold Arrives
The closing months of 2026 present a genuine and unrepeatable opportunity. Positions issued before 1 January 2027 remain outside the expanded delta rules for their life. Therefore, reviewing the derivative book now is materially more valuable than reviewing it in February.
Furthermore, every household with a non-US spouse holding American exposure should confirm three things immediately. First, whether a current Form W-8BEN sits with each broker. Second, whether the Section 871(m) withholding actually applied is fifteen or thirty per cent. Third, whether any combined positions create liabilities the broker has not addressed.
How TaxYork Can Help
TaxYork prepares United States and United Kingdom tax returns for high-net-worth households on both sides of the Atlantic. Consequently, we look at the whole family position rather than one spouse in isolation, which is precisely how these withholding leaks come to light.
Our work on Section 871(m) covers treaty claims, refund filings, disclosure of unreported dividend equivalents, and coordination between American and British reporting. Additionally, our cross-border tax preparation service addresses the structural questions that follow, including whether a section 6013(g) election makes sense for your household.
We have prepared cross-border returns for investment bankers, fund partners, company owners and private investors for many years. Therefore, we understand how a derivative book actually looks in practice, not merely how the regulations describe it.
Conclusion
Section 871(m) turns your British spouse's American derivative exposure into a United States tax event, at thirty per cent unless she claims the treaty rate. Furthermore, the charge frequently strands, because spread betting produces no British tax to credit it against and capital gains treatment of contracts for difference rarely matches an income withholding.
The 2027 expansion widens the perimeter substantially, and positions issued before 1 January 2027 escape it. Therefore, acting during the remaining weeks of 2026 delivers value that acting later cannot. Ultimately, the households that lose the most are those where one spouse receives careful American attention and the other receives none at all.
Contact Us
Speak to us about your household's American withholding exposure before the 2027 rules take effect. You can book a consultation with our cross-border team, email hello@taxyork.com, or telephone 020 3488 8606.
Disclaimer
This article provides general information about Section 871(m) and United States withholding on dividend equivalents. It does not constitute tax advice and should not be relied upon in place of a professional review of your circumstances. Tax law changes frequently, and the application of these rules depends entirely on your individual facts. Please consult a qualified cross-border tax professional before acting.
Written by the TaxYork Expert Team — US-UK tax specialists.