Individual Savings Accounts (ISAs) for US citizens in 2026
US citizens can open a UK Individual Savings Account (ISA) if they meet the UK’s eligibility rules. However, the IRS generally does not recognize an ISA as tax-free. Depending on the type of ISA and the investments it holds, US taxes and additional reporting requirements may still apply.
This guide explains how ISAs affect US citizens, how the IRS typically treats different ISA types, which reporting obligations may apply, and what to consider before investing.
Last updated August 10, 2026
Written by: Clark Stott
In this article
Can I open an Individual Savings Account (ISA) as a US citizen?
Yes. US citizens can open a UK ISA if they meet the UK’s eligibility requirements, although some providers may impose additional restrictions because of US tax reporting rules.
For US expats, there’s simply one extra layer to consider: US citizenship creates an additional consideration because each ISA provider decides whether it will accept US persons. Some providers restrict access because FATCA requires many foreign financial institutions to identify and report accounts held by US persons.
In general, you can open an ISA if you:
- Are aged 18 or over
- Are UK-resident or qualify for a Crown-employee exception
- Are under 40 if opening a Lifetime ISA
- Have a National Insurance number
- Have remaining allowance if you intend to make a new subscription*
- Can find a provider that accepts US persons
*HM Revenue & Customs (HMRC) sets the annual ISA allowance, which remains £20,000 for the 2026/27 tax year across eligible ISA accounts. You can split this allowance across different ISA types if you wish.
If you later move outside the UK, you can usually keep your existing ISA, but in most cases you cannot continue making new contributions unless you qualify for one of HMRC’s limited exceptions, such as certain Crown employees working overseas.
How does the IRS treat an ISA?
The IRS generally does not recognize an Individual Savings Account (ISA) as a tax-free account, even though it receives favorable tax treatment in the UK.
In the UK, eligible ISA holders can generally earn interest, dividends, and capital gains without paying UK tax. From a US perspective, however, an ISA is usually viewed as a standard investment or savings account rather than a special tax-advantaged wrapper. As a result, income generated inside the account may be taxable in the United States, even if no UK tax is due.
That means the tax advantages you enjoy in the UK don’t automatically carry across to your US tax return.
Table 1. UK vs US tax treatment of an ISA
|
UK treatment |
Typical US treatment |
|
Interest is generally tax-free |
Interest may be taxable |
|
Dividends are generally tax-free |
Dividends may be taxable |
|
Capital gains are generally tax-free |
Capital gains may be taxable |
|
No UK reporting of ISA income |
Income may need to be reported on a US tax return |
For example, a Cash ISA typically generates interest, while a Stocks & Shares ISA can hold investment funds, shares, ETFs, and other assets. Because different investments are treated differently under US tax law, two ISA holders may have very different US tax obligations even if both accounts are called an “ISA.”
How do different ISA types affect US taxes?
The type of ISA you choose can make a significant difference to your US tax obligations because the IRS generally looks at the income and investments inside the account rather than the ISA wrapper itself.
Here’s how the main ISA types typically compare.
Table 2. US tax on different ISA types
|
ISA type |
How it works |
Typical US tax considerations |
|
Cash ISA |
Holds cash savings and earns interest. |
Interest is generally taxable in the US, even though it’s tax-free in the UK. |
|
Stocks & Shares ISA |
Holds investments such as shares, funds, bonds, and ETFs. |
Investment income and gains may be taxable. Certain UK funds may also trigger PFIC rules. |
|
Lifetime ISA (LISA) |
Designed to help first-time home buyers or retirement savers, with a UK government bonus. |
US treatment depends on the underlying investments and individual circumstances. The government bonus may require separate US tax analysis. |
|
Innovative Finance ISA |
Holds qualifying peer-to-peer lending investments. |
Interest may still be taxable in the US despite its UK tax-free treatment. |
|
Junior ISA |
Available for US children and the income is generally the child’s US income. |
PFIC rules can apply to funds held inside a Stocks & Shares Junior ISA. The child has their own FBAR obligation if the threshold is exceeded. If the child cannot file, the parent or guardian must file for them. |
Cash ISAs are often the simplest from a US perspective
A Cash ISA is essentially a savings account with UK tax benefits. Although the interest it earns is generally still taxable on a US tax return, it usually doesn’t involve the same level of complexity as investment-based ISAs.
That doesn’t mean there are never US reporting obligations, but the underlying asset, which is typically a cash deposit, is relatively straightforward compared with an investment fund.
Stocks & Shares ISAs deserve closer attention
A Stocks & Shares ISA can become more complicated for US citizens because some of the investments it holds may be treated differently under US tax law, particularly if they are classified as Passive Foreign Investment Companies (PFICs).
For many UK investors, the default choice is a diversified investment fund. These funds are widely used, relatively easy to access, and can be an effective way to build a long-term portfolio. From a US tax perspective, however, some of these same investments may fall under the IRS’s PFIC rules.
What is a PFIC?
A Passive Foreign Investment Company (PFIC) is a foreign corporation that meets certain IRS tests relating to its income or assets. Broadly speaking, a foreign corporation may be treated as a PFIC if:
- At least 75% of its gross income is passive income, or
- At least 50% of its assets produce, or are held to produce, passive income
If one or more investments inside your ISA are classified as PFICs, the IRS may require additional reporting and apply a different set of tax rules than those used for ordinary investments. This can mean:
- A separate Form 8621 for each investment classified as a PFIC
- More complex tax calculations
- Different methods of calculating taxable income
- Greater compliance costs compared with holding investments that aren’t treated as PFICs
Investments that may raise PFIC concerns
Depending on the fund and its structure, examples may include:
- UK mutual funds
- OEICs (Open-Ended Investment Companies)
- Unit trusts
- Some non-US ETFs
By contrast, holding shares in an individual trading company is generally a different situation. For example, buying shares in a listed company that earns most of its income from manufacturing products or providing services would not typically make that investment a PFIC simply because it’s held outside the United States.
Which US tax forms might apply to an ISA?
Owning an ISA doesn’t automatically mean you’ll need additional US tax forms. However, depending on the account, the investments it holds, and the total value of your foreign assets, several US reporting requirements may apply.
The table below provides a general overview.
Table 3. US tax forms that may apply to an ISA
|
Situation |
Possible reporting |
|
Interest or dividends earned inside the ISA |
Form 1040 and Schedule B |
|
Sale of non-PFIC investments |
Form 8949 and Schedule D |
|
Foreign accounts exceeding US$10,000 in aggregate* |
FBAR |
|
Specified foreign assets exceeding the applicable threshold
|
|
|
Investment classified as a PFIC |
Form 8621 |
|
ISA arrangement is classified as a foreign trust |
Forms 3520 and 3520-A may require analysis |
*A Cash ISA or Stocks & Shares ISA maintained by a UK financial institution will generally be a foreign financial account.
Keep in mind that these forms serve different purposes. Filing one doesn’t necessarily satisfy another, and whether you’re required to file depends on your individual circumstances and the applicable IRS rules.
Is an ISA still worth it for a US citizen?
Possibly. An ISA can still provide valuable UK tax benefits, but whether it is worthwhile depends on your financial goals, the type of ISA you choose, and how the investments fit into your overall US tax situation.
An ISA still offers valuable UK tax benefits
Even though the IRS doesn’t generally recognize an ISA as tax-free, the account continues to provide meaningful advantages in the UK.
Depending on the type of ISA, these benefits may include:
- Tax-free interest
- Tax-free dividends
- Tax-free capital gains
- No UK tax reporting on investment income generated within the ISA
For someone planning to remain in the UK long term, those benefits can still be significant.
The trade-off is additional US tax complexity
US taxation does not automatically eliminate the UK benefits, but it can significantly reduce them and increase the annual cost of compliance.
For example, a Cash ISA may require relatively little additional US tax analysis beyond reporting any taxable interest. A Stocks & Shares ISA invested in UK collective investment funds, on the other hand, may involve considerably more compliance because of the investments it holds. That’s why it’s often more useful to evaluate the investment strategy than the ISA itself.
Rather than asking whether an ISA is “good” or “bad,” it’s more helpful to ask whether it fits your overall financial situation. Before opening or contributing to an ISA, consider:
- Your long-term financial goals
- The investments you plan to hold
- Whether those investments could trigger additional US reporting
- How both the UK and US tax rules affect your overall outcome
If you’re unsure how an ISA fits into your circumstances, it may be worth speaking with a tax professional who understands both US and UK tax rules. A little planning upfront can help you avoid unexpected reporting requirements and make more informed investment decisions.
What alternatives can US citizens consider?
An ISA isn’t the only way for US citizens living in the UK to save or invest. Depending on your goals and US tax situation, other options may be worth exploring.
Potential alternatives include:
- Individual shares instead of certain collective investment funds, which may reduce the likelihood of PFIC-related issues.
- UK pension contributions, which may receive different tax treatment under the US-UK Income Tax Treaty than an ISA. Article 18 can protect qualifying contributions and growth for certain taxpayers, but the result depends on residence, employment, the pension arrangement and the applicable US limits.
- Other investment strategies that better align with both UK and US tax rules, depending on your circumstances.
The right alternative depends on what you’re trying to achieve. Some people prioritize simplicity and lower US tax complexity, while others focus on long-term growth or retirement planning.
Frequently Asked Questions
Does the US-UK tax treaty make an ISA tax-free?
No. The US-UK Income Tax Treaty provides special treatment for certain pension arrangements, but it does not generally extend the same tax benefits to Individual Savings Accounts (ISAs). As a result, income earned inside an ISA may still be taxable in the United States.
Can I keep my ISA if I move out of the UK?
Yes. You can generally keep your existing ISA after becoming a non-UK resident. However, you usually cannot make new contributions unless you qualify for one of HMRC’s limited exceptions, such as certain Crown employees working overseas.
Does a Cash ISA have PFIC issues?
Generally, no. A Cash ISA holds cash deposits rather than investment funds, so it doesn’t typically create PFIC concerns. However, any interest earned may still be taxable on your US tax return.
Can I transfer my ISA to another provider?
Yes. HMRC allows eligible ISA transfers between providers without losing the account’s tax-advantaged status, provided the transfer follows the official ISA transfer process rather than withdrawing and redepositing the funds.
Do I need to report every ISA on my US tax return?
Income from every ISA must be considered when preparing your US tax return. Taxable interest, dividends, gains and PFIC income generally must be reported when you have a US return filing requirement. Separately, the ISA account may need to be disclosed on Schedule B, the FBAR and Form 8938, depending on the applicable rules and thresholds.
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Clark Stott has been with Expat Tax Online since 2015. Being a dual national based in the UK, Clark has unique experience helping US citizens (and Accidental Americans) become tax compliant via the Streamlined Tax Amnesty program. Clark likes to help Americans in the UK keep their tax situations as simple as possible to avoid harsh IRS treatment.
