Written by Jonathan Laws, ACA, Ch.MCSI, Senior Independent Financial Adviser, Cameron James
If you are a US citizen or green card holder living in the UK, the ISA is one of the more frustrating parts of your financial life. On paper it is the simplest tax wrapper in the country: 20,000 pounds a year, no UK tax on income, no UK tax on gains, and nothing to report on a UK tax return. In practice, many US taxpayers in the UK either cannot open one at all, or open one and then find that almost everything on the investment menu creates a US tax problem. This guide sets out what actually stops US taxpayers from using an ISA properly, and what can be done about it.
Not sure whether your ISA holds PFICs?
We review what is actually inside the wrapper and quantify the reporting you are already carrying. One adviser, both tax systems.
Key Takeaways
- US citizens who are UK resident can open and hold an ISA. Citizenship is not the barrier. The difficulty is finding a provider that will accept a US person and, separately, finding investments inside the ISA that are not PFICs.
- An ISA is a UK tax wrapper only. The IRS does not recognise it, so income and gains inside an ISA remain reportable and taxable in the US.
- Most UK and Irish domiciled funds, including UCITS ETFs, OEICs, unit trusts and investment trusts, are PFICs. Holding them can create punitive US tax treatment and an annual Form 8621 for each fund.
- US-domiciled ETFs are not PFICs, and US-listed ETFs with HMRC reporting fund status can be ISA-qualifying investments. What blocks them on retail platforms is a UK distribution and disclosure requirement, not ISA eligibility.
- Advisers who are not SEC authorised may be limited to recommending individual stocks and bonds to US-connected clients, because the funds route is closed to them.
- Cameron James advisers are SEC authorised, and can advise UK-resident US-connected clients on qualifying US-listed ETFs inside an ISA, a general investment account and a SIPP.
- Cameron James does not charge an initial advice fee on US-connected investments or US pensions.
- Two UK tax changes make this more pressing: dividend rates rose in April 2026, and from April 2027 savings rates rise and the cash ISA allowance for under-65s falls.
Why This Matters More From 2027
Two developments have made the ISA question more pressing for US taxpayers. First, UK tax on investment income is rising. From 6 April 2026 the dividend ordinary rate increased to 10.75 per cent and the upper rate to 35.75 per cent, with the additional rate unchanged at 39.35 per cent. From 6 April 2027 the savings basic, higher and additional rates rise to 22, 42 and 47 per cent (HMRC policy paper, Changes to tax rates for property, savings and dividend income, November 2025).
Second, from 6 April 2027 the cash ISA allowance for those under 65 falls from 20,000 pounds to 12,000 pounds, with the balance of the overall 20,000 pound allowance available only through stocks and shares and other non-cash ISAs. Savers aged 65 and over keep the full 20,000 pound cash allowance (HM Treasury, Autumn Budget 2025). The ISA is becoming both more valuable and more investment-focused at precisely the point where the investment side is hardest for a US person to solve. Note also that the Government has published anti-circumvention rules to sit alongside the change, which are worth checking before assuming cash can simply be held inside a stocks and shares ISA instead.
Can a US Citizen Open an ISA in the UK?
Yes. ISA eligibility turns on UK residence, not nationality or tax citizenship. If you are 18 or over and UK resident for tax purposes, you qualify for the 20,000 pound annual ISA allowance in 2026/27, and you can hold cash ISAs, stocks and shares ISAs and innovative finance ISAs within that limit. HMRC does not exclude US citizens from the ISA regime.
The barrier is commercial and regulatory rather than statutory. Many UK ISA providers restrict or decline applications from US persons, and a number of those that do accept them will not permit the investments that would make the ISA genuinely worth having.
Why some providers decline US persons
- FATCA reporting. Providers accepting US persons take on account identification and reporting obligations, and some have decided the administrative burden is not commercially worthwhile.
- US securities and advice rules. Dealing with, or advising, a US person can engage US regulatory requirements that a UK-only firm is not set up to meet.
- Internal risk policy. Several large platforms have narrowed their acceptance criteria over recent years, sometimes closing existing accounts rather than only refusing new ones.
This is not universal, and it is not static. Provider policies differ, and they change. But it is common enough that many US taxpayers in the UK reach the same dead end.
What the IRS Does With Your ISA
This is the part that catches people out. An ISA is a creature of UK law. The US-UK double tax treaty does not give it the protected status it affords to certain pensions, and the IRS therefore looks straight through the wrapper. In practical terms:
- Income and gains arising inside an ISA are taxable in the US as they arise or are realised, and go on your Form 1040.
- Cash ISA interest is simply US-taxable interest income.
- Dividends and realised gains inside a stocks and shares ISA are US-taxable in the ordinary way, subject to the PFIC rules below.
- The account is likely reportable on the FBAR, FinCEN Form 114, where your aggregate foreign financial accounts exceed 10,000 US dollars at any point in the year, and potentially on Form 8938 depending on your filing status and where you live.
- Whether a particular ISA is treated as a foreign grantor trust, bringing Forms 3520 and 3520-A into play, depends on how that ISA is legally structured and on the position taken by your US tax preparer. Revenue Procedure 2020-17 provides relief from those filings for certain tax-favoured foreign non-retirement savings trusts meeting its conditions. Practice varies between preparers, and this is worth settling before you open an account rather than afterwards.
The asymmetry that matters most
Because you pay no UK tax inside an ISA, you generate no UK tax credit to set against the US tax due. In an ordinary UK taxable account, UK tax paid can generally be credited against the US liability, so you broadly end up paying the higher of the two rates rather than both. Inside an ISA the UK side is nil, and the US tax falls due in full with nothing to offset it. The ISA still saves you the UK tax, which is real and worth having. It simply does nothing for you on the US side. Tax laws are complex and vary by individual circumstance.
The PFIC Problem: Why the Standard ISA Fund Menu Does Not Work
Almost every pooled fund domiciled outside the US is a passive foreign investment company, including UK OEICs and unit trusts, Irish and Luxembourg domiciled UCITS funds, UCITS ETFs listed in London, and UK investment trusts. In other words, it covers most of what a UK stocks and shares ISA will offer you. Our guide to investing as a US citizen in the UK explains how the PFIC rules work and how they interact with UK disclosure rules across every wrapper. What follows here is the part specific to an ISA.
Under the default section 1291 excess distribution regime, the consequences are severe:
- Gains on disposal and excess distributions are allocated back across your holding period and taxed at the highest ordinary income rate applying in each of those years.
- An interest charge is added on top, to claw back the benefit of deferral.
- Preferential long-term capital gains rates are not available.
- Losses cannot be used in the way you would normally expect.
- A separate Form 8621 is required for each PFIC, each year, with a real and recurring preparation cost. Investors holding a handful of funds routinely find their US return costs more than the ISA saves them in UK tax.
Do the PFIC elections help?
The qualified electing fund election is the most favourable treatment, but it is usually unavailable in practice, because UK and Irish fund managers do not generally produce the PFIC Annual Information Statement the election depends on.
A mark-to-market election may be available where the holding is marketable stock on a qualified exchange. It removes the interest charge, but it taxes unrealised gains annually as ordinary income and restricts loss relief, and Form 8621 is still required each year. It is a mitigation for a position you already hold, not a reason to buy PFICs in the first place.
Your ISA and your SIPP need different answers
PFIC reporting does not bite in the same way inside a UK SIPP. Investments held within a SIPP during accumulation sit outside the PFIC reporting regime, so a US-connected client can hold UK-domiciled funds in a SIPP without the same consequences. An ISA has no such protection. That is why the ISA and the SIPP of a US taxpayer often need entirely different investment approaches, and why advice that treats the two wrappers identically should prompt a second opinion.
Can US-Listed ETFs Be Held Inside an ISA?
Yes, where the fund meets the ISA qualifying investment conditions. This is where a good deal of published commentary is either wrong or incomplete, because two entirely separate questions get run together.
Question one: is a US-listed ETF an ISA-qualifying investment?
Broadly, yes, where it is admitted to trading on a recognised stock exchange and holds HMRC reporting fund status. Being outside the UCITS framework does not, by itself, make a fund ineligible for an ISA. Reporting fund status matters independently as well, because without it any holding outside an ISA would face offshore income gain treatment for UK purposes, so it is worth checking a fund against the published HMRC reporting fund list in any event.
Question two: will a UK retail platform sell it to you?
Usually not, and that is a distribution question rather than a tax or eligibility one. To be marketed to UK retail investors, an overseas fund generally needs recognised scheme status, now principally through the Overseas Funds Regime. Separately, UK retail disclosure rules require a standardised disclosure document for the product.
Some commentary suggested that the Consumer Composite Investments reform would open up US-domiciled ETFs to UK retail investors. It has not. The UK PRIIPs Regulation was repealed on 6 April 2026 and replaced by the CCI regime under FCA Policy Statement PS25/20, with an optional transition running to 8 June 2027 (FCA PS25/20, December 2025). That reform changed the format of the retail disclosure document. It did not remove the underlying recognition requirement sitting behind it, and US ETF managers have generally not produced UK retail disclosure documents under either regime.
The distinction is the whole point. What exists is a barrier to mass-market retail distribution. It is not a rule that the asset cannot be held inside an ISA. Under an advised arrangement with an SEC authorised adviser, the position is different, and qualifying US-listed ETFs can be held by UK-resident US-connected clients inside an ISA, a general investment account and a SIPP.
A warning about the DIY workaround
Interactive Brokers is frequently suggested in forums as a way around this. It is not. Elective professional investors were previously able to hold US-listed ETFs this way, but since April 2025 Interactive Brokers has treated US ETFs as non-qualifying investments that are not eligible to be held in an ISA. It is not a route to US-listed ETFs in any UK wrapper.
Why the Authorisations of Your Adviser Determine Your Investment Options
Two different permissions are in play here, and they are frequently muddled together, including by advisers.
FCA authorisation is what permits a firm to advise a UK resident on a UK product such as an ISA. If you live in the UK, that is the necessary starting point.
SEC authorisation is a separate matter entirely. Where the client is a US person, advising on US securities engages the US regulatory regime, and the adviser needs to be SEC authorised in their own right. Holding FCA permissions does not confer it.
An adviser who holds only FCA authorisation faces a narrowed menu the moment the client is a US taxpayer. UK and Irish domiciled funds are PFICs and are generally best avoided outside a pension wrapper. US-domiciled funds sit outside what that adviser can advise on. What remains is individual stocks and bonds.
Is a portfolio of individual stocks and bonds a bad answer?
No, and it would be unfair to suggest otherwise. Direct equity and bond mandates are a perfectly legitimate approach for US-connected clients. They sidestep PFIC entirely, they allow tax-lot level control that can be genuinely useful to a US filer, and at larger portfolio sizes a well-constructed direct mandate can work very well. Past performance is not a guide to future results, and the value of investments can fall as well as rise.
The trade-offs are real, though, and they fall hardest on small and mid-sized portfolios:
- Diversification. Reproducing broad-market exposure with individual holdings takes far more positions, and far more dealing, than buying a single index fund.
- Cost. Dealing charges, spreads and the management fee on a direct mandate will typically exceed the handful of basis points charged by a broad-market ETF.
- Stock-specific risk. Concentration is harder to control and easier to accumulate unintentionally.
- Fixed income. Building a properly diversified bond allocation from individual issues is difficult at retail portfolio sizes, and often ends up either concentrated or expensive.
- Maintenance. Rebalancing, corporate actions and dividend reinvestment all take more work and more transactions.
The question worth putting to any adviser is a simple one: is this the best solution available to me, or the best solution available to you? Those are not always the same answer, and you are entitled to know which one you are being offered. If the answer to “why individual stocks rather than funds?” is about the permissions of the adviser rather than your circumstances, that is useful information.
Is an ISA Actually Worth Having as a US Citizen?
Sometimes clearly yes, sometimes not, and the honest answer depends on your circumstances.
The case for
- If you expect to remain UK tax resident for the long term, the UK tax saved is real and compounds over time, and it is growing as UK rates on dividends and savings income rise.
- No UK capital gains tax on disposals, no UK tax on dividends or interest, and nothing to report to HMRC.
- Unlike a pension, there is no lock-in and no minimum access age.
The case for caution
- There is no US tax shelter at all, and no UK tax credit generated to offset the US liability.
- You take on additional US reporting, and potentially the foreign trust question.
- If you are likely to return to the US in the near term, the UK benefit may be short-lived relative to the complexity.
- An ISA filled with PFICs is very often worse than a plain taxable account holding non-PFIC assets. The wrapper does not rescue a poor investment choice for a US filer, and in the worst cases it disguises one.
That final point is the one to take away. For a US taxpayer, the value of an ISA depends almost entirely on what you are able to put inside it.
A Practical Checklist
- Confirm the provider accepts US persons, and get it in writing before you transfer anything.
- Confirm what you can actually hold once the account is open, not just that the account can be opened.
- Check HMRC reporting fund status for anything you intend to buy, against the published HMRC list.
- Agree the US reporting position, including the Form 3520 question, with your US tax preparer in advance.
- Review any existing ISA holdings for PFIC exposure, and quantify the Form 8621 cost you are already carrying.
- Check the authorisations of your adviser, specifically whether they are SEC authorised, and ask what that means for what they can recommend.
- Coordinate the ISA with your SIPP and any US retirement accounts, because the three wrappers need different treatment.
How Cameron James Works With US Citizens in the UK
Cameron James Ltd is an FCA-authorised cross-border financial planning firm working with UK expatriates, non-UK residents and US-connected persons. Several Cameron James advisers are also SEC authorised, which is what allows us to advise US-connected clients on US-listed investments.
For a UK-resident US taxpayer, that means:
- An ISA, a general investment account and a SIPP can each be built using qualifying US-listed ETFs rather than PFICs.
- No section 1291 regime, and no Form 8621 for each holding, on the ETF side of the portfolio.
- One adviser looking at the UK and US positions together, rather than a UK adviser who cannot see the US consequences of their own recommendation.
- Existing PFIC-heavy ISAs can be reviewed and restructured, with the US tax consequences of unwinding them modelled before anything is sold.
No initial advice fee on US-connected investments or US pensions
Cameron James does not charge an initial advice fee on US-connected investments or on US pensions. There is no upfront charge for the advice, the analysis or the implementation.
That matters more than it might sound in this particular context. US-connected clients are routinely quoted a percentage-based initial fee running into several thousand pounds simply to move into a compliant structure. Where the problem you are solving is an ISA that has quietly been accruing PFIC exposure for years, a large upfront fee can make fixing it look uneconomic, and so people leave it. Removing the initial fee removes that obstacle, and means the decision can be made on its merits.
What is charged is an ongoing advice fee for continuing management and reviews, alongside the underlying platform and fund costs. All charges are set out on our costs page, and are disclosed in full and in writing before you commit to anything.
What This Means for You
If you are a US citizen or green card holder in the UK, the question is not really whether to have an ISA. It is what you would be able to put inside it.
Start by establishing two facts. First, whether your provider accepts US persons, in writing. Second, what is currently inside any ISA you already hold, and whether those holdings are PFICs. Many people discover they have been carrying Form 8621 obligations for years without realising it.
If your ISA is full of UK or Irish domiciled funds, the position needs modelling rather than immediate action, because disposing of a PFIC is itself a taxable event. If you are yet to open one, the sequence matters: settle the reporting position with your US preparer first, then the provider, then the investments.
Individual circumstances vary a great deal, and tax laws are complex and vary by individual circumstance. Nothing here is a substitute for coordinated advice on your own position, taken with a US tax preparer alongside a regulated adviser.
Estate Planning, Inheritance Tax Planning, and Tax Planning are not regulated by the Financial Conduct Authority
Next Step: A Free Review of Your ISA
The question is not which wrapper to use. It is what is already inside the one you have, and what it is costing you on the US side.
Frequently Asked Questions
Yes, provided you are 18 or over and UK resident for tax purposes. ISA eligibility is based on UK residence, not nationality. The practical difficulty is that many UK providers restrict applications from US persons, and many of those that accept them offer an investment range consisting largely of PFICs.
It is tax-free for UK purposes only. The IRS does not recognise the ISA wrapper, so income and gains inside the account remain taxable in the US as they arise or are realised, and are reported on your Form 1040. Because no UK tax is paid, no UK tax credit is generated to offset the US liability.
Yes, and it makes the investment question harder rather than easier. From 6 April 2027 the cash ISA allowance for those under 65 falls to 12,000 pounds, with the balance of the overall 20,000 pound allowance available only through stocks and shares and other non-cash ISAs. For a US taxpayer that means more of the allowance has to be used in the wrapper where the PFIC problem lives. Anti-circumvention rules have been published alongside the change, so check them before assuming cash can simply be held inside a stocks and shares ISA instead.
US-listed ETFs with HMRC reporting fund status can be ISA-qualifying investments. What generally prevents access is a UK distribution and disclosure requirement that applies to marketing overseas funds to retail investors, rather than any rule that the asset cannot sit inside an ISA. Under an advised arrangement with an SEC authorised adviser, qualifying US-listed ETFs can be held inside an ISA, a general investment account and a SIPP.
No. The UK PRIIPs Regulation was repealed on 6 April 2026 and replaced by the Consumer Composite Investments regime, with a transition period running to 8 June 2027. The reform changed the format of the retail disclosure document rather than removing the underlying recognition requirement for overseas funds, and US ETF managers have generally not produced UK retail disclosure documents under either regime.
It avoids the PFIC problem, because cash is not a fund, but it does not avoid US tax. Interest arising inside a cash ISA is simply US-taxable interest income on your Form 1040, and because no UK tax is paid there is no UK credit to offset it. The account remains FBAR-reportable in the ordinary way. From April 2027 the cash allowance for those under 65 also falls to 12,000 pounds, so a cash-only approach uses less of the allowance than it used to.
An ISA is a foreign financial account, so it is generally FBAR-reportable where your aggregate foreign accounts exceed 10,000 US dollars at any point in the year, and may also be reportable on Form 8938 depending on your filing status and where you live. Whether Forms 3520 and 3520-A are also required depends on the structure of the particular ISA and the position of your preparer, taking Revenue Procedure 2020-17 into account.
Not necessarily, and not without modelling it first. Disposing of a PFIC is itself a taxable event under the section 1291 rules, so the exit cost needs to be weighed against the ongoing cost of holding and reporting it. The right sequence, and whether to use a mark-to-market election in the meantime, depends on how long the holding has been in place and its size.
No. Cameron James does not charge an initial advice fee on US-connected investments or US pensions. An ongoing advice fee applies for continuing management and reviews, and the underlying platform and fund costs are disclosed in full before you commit.
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Jonathan Laws, ACA Ch.FCSI, Senior Independent Financial Adviser, Cameron James
“Almost nobody who comes to me about an ISA has done anything wrong. They opened the account the sensible way, picked a low cost index fund, and had no idea that the fund was the problem rather than the wrapper. Finding that out five years in is unsettling, and the first thing I usually say is that it is fixable.
What I would not do is rush to sell. Disposing of a PFIC is itself a taxable event, so the exit needs modelling before anything is traded. The order of operations matters more than the individual fund choice, and getting that order right is most of the work.
The honest answer on whether an ISA is worth having is that it depends entirely on what you can put inside it. That is a solvable question, and it is worth answering properly before you contribute another year of allowance.”