Do I have to report a UK ISA on the FBAR if it is tax-free in the UK?

Yes. A UK ISA is a foreign financial account because it is held with a financial institution outside the United States. FinCEN requires a US person to file an FBAR when the aggregate value of foreign financial accounts exceeds $10,000 at any time in the calendar year. The IRS confirms the requirement applies whether or not the account produces taxable income, so the ISA's UK tax exemption is irrelevant.

Is a stocks and shares ISA a bank account or a securities account on the FBAR?

A stocks and shares ISA is reported as a securities account, and a cash ISA is reported as a bank account. The stocks and shares ISA is listed once, as the account held with the platform or manager, using its ISA or portfolio reference. The funds and shares inside it are not listed as separate accounts. Its maximum value includes both investments and uninvested cash.

How do I work out the maximum value of a stocks and shares ISA for the FBAR?

Take the highest value of the ISA during the calendar year in sterling, counting investments and cash together, using statements issued at least quarterly that fairly reflect the peak. Then convert that figure to US dollars using the Treasury Reporting Rates of Exchange for the last day of the calendar year. IRS Publication 5569 describes the result as a reasonable approximation of the greatest value in the account.

Do I report an ISA that I closed or transferred to another provider?

Yes. An ISA that existed at any time during the calendar year is reportable for that year, with its maximum value up to closure. When an ISA is transferred between providers, the old and new accounts are both listed for the transfer year, each with its own institution details and account number. HMRC treats a transfer as continuous ISA saving, but the FBAR treats it as two accounts.

What is the penalty for a non-willful Missed FBAR on an ISA after Bittner?

The non-willful civil penalty is capped at a statutory $10,000, adjusted annually for inflation under 31 CFR 1010.821, and it does not apply where the violation was due to reasonable cause. In Bittner v. United States the Supreme Court held the penalty applies per report, not per account, so several omitted ISAs on one year's FBAR amount to one violation for that year.

Should I use the streamlined procedures or just file the late FBARs?

It depends on your tax returns. If all ISA income was reported and only the FBAR was missed, late FBARs are filed directly through FinCEN's BSA E-Filing System with a reason for late filing. If ISA interest, dividends, gains or PFIC forms were also omitted, non-willful taxpayers living abroad normally use the Streamlined Foreign Offshore Procedures: three years of returns, six years of FBARs and Form 14653.

Missed FBAR on a UK ISA: Cash and Stocks and Shares ISAs

Missed FBAR filings on a UK ISA are among the most common omissions we find when we prepare US returns for Americans living in Britain, and the cause is nearly always the same sentence: an ISA is tax-free, so there is nothing to report. That is true for HMRC and wrong for the United States. A cash ISA is a foreign bank account and a stocks and shares ISA is a foreign securities account, and both belong on FinCEN Form 114 (the FBAR) for every calendar year in which your non-US accounts together went above $10,000 at any point. The fix is to file the late reports through the BSA E-Filing System, on their own or within a streamlined submission.

This guide deals with the adult ISAs that high earners and investors actually hold: the cash ISA, the stocks and shares ISA and, briefly, the innovative finance ISA. The Lifetime ISA, Help to Buy ISA and Junior ISA are covered in separate articles on this site and are not repeated here.

Is a UK ISA reportable on the FBAR even though it is tax-free in the UK?

Yes. An ISA is a foreign financial account for FBAR purposes because of where it is held, not because of how it is taxed. FinCEN states at fincen.gov/report-foreign-bank-and-financial-accounts that a United States person with a financial interest in or signature authority over foreign financial accounts must file if the aggregate value of those accounts exceeds $10,000 at any time during the calendar year. Nothing in that test asks whether the account is tax-favoured in the country where it sits.

The IRS FBAR Reference Guide, Publication 5569 at irs.gov/pub/irs-pdf/p5569.pdf, lists what counts as a financial account: bank accounts such as savings and checking accounts and time deposits, securities accounts such as brokerage accounts, mutual funds or similar pooled funds, and any other account maintained in a foreign financial institution. The guide does not mention the ISA by name, but it gives the Canadian Tax-Free Savings Account as an example of a foreign financial account that is reportable on the FBAR. The TFSA is the closest foreign equivalent to an ISA, and the reasoning carries straight across.

Two further statements in the official material close off the usual objections. The IRS FBAR page at irs.gov/businesses/small-businesses-self-employed/report-of-foreign-bank-and-financial-accounts-fbar confirms that an account at a financial institution located outside the United States is a foreign financial account, and that the filing requirement applies whether or not the account produced taxable income. Publication 5569 adds that tax treaties with the United States do not affect FBAR filing obligations. So neither the ISA's UK tax exemption nor the US-UK income tax treaty takes an ISA off the form.

Why do so many Americans in the UK end up with a Missed FBAR on an ISA?

In the files we take on, the pattern is consistent. The reader has usually filed US returns every year, often with a preparer, and has reported the obvious accounts. The ISAs are left out for reasons that feel sensible at the time, and none of them is evidence of anything other than a misunderstanding, which matters later when non-willful conduct is assessed.

The ISA never appears on a UK self assessment return, so it does not appear on the document pack handed to the US preparer.
The provider issues no UK tax certificate for an ISA, so there is no piece of paper that prompts the question.
A stocks and shares ISA held on an investment platform is thought of as an investment, not as an account, and the FBAR is thought of as a bank account form.
The preparer's organiser asked about foreign bank accounts and the client answered the question literally.

How is a cash ISA reported on the FBAR?

A cash ISA is reported as a bank account. Each cash ISA is its own line in the account section of FinCEN Form 114, separate from any current account or ordinary savings account you hold with the same institution. The information required matches the records Publication 5569 tells filers to keep: the name in which the account is maintained, the account number or other designation, the name and address of the foreign financial institution, the type of account and the maximum value during the year. Use whatever number the provider uses to identify that specific ISA on its statements, which for fixed-rate products may be a plan reference instead of a sort code and account number.

How is a stocks and shares ISA reported, and what is its maximum value?

A stocks and shares ISA is reported as a securities account. You report the ISA account itself, held with the platform or investment manager, as one account. You do not list each fund or share held inside it as a separate FBAR line, because the holdings sit in a custodial account and it is that account you have a financial interest in. The financial institution is the ISA manager shown on your statements, and the account number is the ISA or portfolio reference the platform uses.

The maximum value is where most errors occur. Publication 5569 defines the maximum value of an account as a reasonable approximation of the greatest value of currency and non-monetary assets in the account during the calendar year. For a stocks and shares ISA that means the market value of the funds and shares plus any uninvested cash held within the ISA, taken at the highest point of the year, not the amount you subscribed and not simply the 31 December valuation. The guide allows you to rely on periodic account statements issued at least quarterly, provided they fairly reflect the maximum value during the year.

The conversion step is mechanical. You determine the maximum value in sterling first, then convert it to US dollars using the Treasury Reporting Rates of Exchange for the last day of the calendar year, as Publication 5569 directs. You do not use the rate on the day the account peaked. Note also that the FBAR runs on the calendar year, while ISA statements and subscriptions follow the UK tax year ending 5 April. A valuation dated 5 April is useful evidence but it straddles two FBAR years, so in practice we ask the platform for quarterly or monthly valuations covering January to December.

What about an innovative finance ISA?

The innovative finance ISA is listed alongside the cash ISA and the stocks and shares ISA on gov.uk/individual-savings-accounts. It is an account maintained with a UK ISA manager, so in the FBARs we prepare it is reported too, normally under the other financial account category, at the highest combined value of positions and uninvested cash in the year. Its income is taxable in the United States in the same way as cash ISA interest.

Do several ISAs, transfers between providers and closed ISAs all need reporting?

Yes, and this is the area where competing guides say least. An investor who has used the ISA allowance for fifteen years rarely has one ISA. The typical position is several cash ISAs, one or two stocks and shares ISAs and at least one transfer between providers. Each of these is a separate account for FBAR purposes for every calendar year in which it existed, however small the balance.

Transfers need particular care. When you transfer an ISA from one provider to another, the UK rules treat it as the same ISA savings continuing. The FBAR does not. The account with the old provider existed for part of the year and the account with the new provider existed for the rest, so the FBAR for the transfer year lists both, each with its own institution details, account number and maximum value. The same money therefore appears twice on that year's form. That is the correct result, and it also means the transfer year is the one in which a filer is most likely to have left an account off.

Closed and matured ISAs are our first gap angle, because they are the accounts people are most confident they can ignore. The FBAR test looks at the value of your foreign accounts at any time during the calendar year. An ISA that was open on 1 January and closed in March is reportable for that year, with its maximum value up to the date of closure. A streamlined submission requires FBARs for the most recent six years for which the FBAR due date has passed, so a full catch-up means reconstructing the account list year by year across that window, including accounts that no longer exist.

How does the $10,000 aggregate threshold work with other UK accounts?

The threshold is an aggregate test across every foreign financial account, not a test applied to each account. Publication 5569 illustrates this with a filer holding three accounts with balances of $3,000, $1,000 and $8,000, who must report all three because the total is over $10,000 even though no single account is. Once the aggregate is exceeded, every account is reported, including an old cash ISA with a few hundred pounds in it.

Married couples should note one consequence of the ISA rules. GOV.UK confirms that you cannot hold an ISA with someone else, so every ISA is in one name. Publication 5569 allows a spouse to be covered by the other spouse's FBAR only where all of the non-filing spouse's reportable accounts are jointly owned with the filing spouse and Form 114a has been completed and signed. An ISA in your sole name breaks that condition. Where both spouses are US persons and each holds an ISA, each files their own FBAR. Where your spouse is not a US person, their ISA is not your account and is not reported by you unless you have signature authority over it.

Does an ISA also go on Form 8938?

Often, yes. Form 8938 is a separate IRS form attached to the income tax return, with much higher thresholds than the FBAR. The IRS comparison at irs.gov/businesses/comparison-of-form-8938-and-fbar-requirements sets the thresholds for taxpayers living abroad at more than $200,000 on the last day of the tax year or more than $300,000 at any time during the year for unmarried filers and those married filing separately, and more than $400,000 on the last day or more than $600,000 at any time for married couples filing jointly. The same page confirms that foreign deposit and custodial accounts at foreign financial institutions are reportable on both forms.

Long-held ISAs alone can exceed those figures, and filing one form does not satisfy the other. Anyone with a Missed FBAR for an ISA should check at the same time whether Form 8938 was filed with the ISAs listed. The IRS comparison page puts the penalty for failure to disclose at up to $10,000, with further amounts for continued non-filing after IRS notification.

Is ISA income taxable in the US, and are the funds inside PFICs?

The reporting question and the tax question are separate, but they travel together. US citizens and residents are taxed on worldwide income, and US tax law has no equivalent of the ISA exemption. Interest on a cash ISA is reported on the US return as interest income. Dividends and realised gains inside a stocks and shares ISA are reported in the year they arise, whether or not anything is withdrawn.

The harder issue is the passive foreign investment company rules. The Form 8621 instructions at irs.gov/instructions/i8621 define a PFIC as a foreign corporation that meets either an income test, where 75% or more of its gross income is passive, or an asset test, where at least 50% of its assets produce or are held to produce passive income. UK-domiciled funds and exchange-traded funds of the kind commonly held in a stocks and shares ISA usually meet that definition. A separate Form 8621 is required for each PFIC, and without a qualified electing fund or mark-to-market election the default excess distribution regime applies, with gains taxed as ordinary income and an interest charge on amounts allocated to earlier years. If the ISA was left off the FBAR, its income and Forms 8621 were very likely left off the return too, which changes the correction route.

How much can go into an ISA each year?

GOV.UK states at gov.uk/individual-savings-accounts that in the 2026 to 2027 tax year the maximum you can save in ISAs is £20,000 and that you must be 18 or over to open one. The limit matters here in one respect only: it explains why balances build so quickly. A reader who has subscribed at or near the limit for many years, with investment growth on top, will usually hold ISAs well into six figures, which is why Form 8938 and the PFIC rules tend to be in play alongside the FBAR.

How are late FBARs for an ISA filed now?

Late FBARs are filed in the same place as timely ones: electronically, through the BSA E-Filing System at bsaefiling.fincen.gov. The FBAR is due on 15 April following the calendar year, with an automatic extension to 15 October that does not need to be requested. For earlier years, Publication 5569 explains that a US person who learns they should have filed enters the calendar year being reported on the online form and either selects a reason that explains the late filing or selects Other and uses the text box, which takes up to 750 characters, to explain the late filing or to indicate that the filing is made in conjunction with an IRS compliance option. There are two realistic routes, and which one applies depends on the tax return, not on the FBAR.

Route one, FBAR-only omission. All ISA income was reported on the US returns and any tax was paid, and the only failure is that the ISAs were left off the FBAR or no FBAR was filed. The late or corrected FBARs are filed directly through BSA E-Filing with an accurate reason for late filing.
Route two, income was also omitted. ISA interest, dividends, gains or PFIC reporting were left off the returns. For non-willful taxpayers living outside the United States this is normally corrected through the Streamlined Foreign Offshore Procedures, with the late FBARs filed as part of that submission.

Under the Streamlined Foreign Offshore Procedures, described at irs.gov/individuals/international-taxpayers/u-s-taxpayers-residing-outside-the-united-states, the taxpayer files delinquent or amended returns for the most recent three years for which the due date has passed, with all required information returns, files delinquent FBARs for the most recent six years, pays the tax and interest due, and signs a non-willful certification on Form 14653. The non-residency test for US citizens is at least 330 full days outside the United States, with no US abode, in at least one of those three years. The IRS states that a taxpayer who complies with the foreign offshore procedures is not subject to failure-to-file, failure-to-pay, accuracy-related, information return or FBAR penalties. For the FBARs in that submission, the IRS instructs filers to select Other as the reason for late filing and enter Streamlined Filing Compliance Procedures as the explanation.

Why is an FBAR-only omission the easier case?

This is our second gap angle, and it applies to more people than expected. Some filers did report their cash ISA interest every year, because their preparer asked for all interest received, and simply never added the ISA to the FBAR account list. Others hold a stocks and shares ISA invested only in individual shares, reported the dividends and disposals correctly, and missed the FBAR line. In those cases there is no unreported income and no additional tax.

That makes the correction simpler for three reasons. There is no tax return to amend, so there is nothing to submit to the IRS beyond the FBARs themselves, which go to FinCEN. The explanation for the late filing is short and credible, because full reporting of the income is strong evidence that the omission was a misunderstanding about a form. And Publication 5569 states that if the account is properly reported on a late-filed FBAR and the IRS determines the violation was due to reasonable cause, no penalty will be imposed.

The discipline in this route is accuracy: every account for each year, including closed ISAs and both sides of every transfer, with defensible maximum values.

What is the non-willful FBAR penalty framework after Bittner?

The statute allows a civil penalty for a non-willful FBAR violation that is not due to reasonable cause. Publication 5569 gives the authority as 31 USC 5321(a)(5)(B) and the amount as up to the figure in the penalty adjustment table at 31 CFR 1010.821, a statutory $10,000 ceiling that is adjusted each year for inflation. The guide notes that civil FBAR penalties have upper limits but no minimum.

In Bittner v. United States, decided in 2023, the US Supreme Court held that the non-willful penalty applies per report, not per account. That matters a great deal to ISA holders. A filer with eight ISAs and three bank accounts omitted from one year's FBAR has one non-willful violation for that year, not eleven. The Internal Revenue Manual at irs.gov/irm/part4/irm_04-026-016 was revised to incorporate the decision and records that a single non-willful reporting violation can result in only a single penalty. The same manual directs examiners to consider whether a warning letter, Letter 3800, together with securing the delinquent or corrected FBARs, is sufficient in place of a penalty, and confirms that no penalty should be imposed where the violation was due to reasonable cause and accurate late FBARs are filed.

Worked scenario: three ISAs, one transfer and one closed account

The following is an illustration only. The figures are invented, and the exchange rate of $1.30 to £1 is an assumption used for arithmetic, not the Treasury rate for any year. Sarah is a US citizen who has lived in London for twelve years and files a US return each year with FBARs listing her current account and a savings account. She has never listed an ISA.

In the calendar year under review Sarah held a current account with a maximum value of £9,000, a fixed-rate cash ISA with a maximum value of £42,000 and a stocks and shares ISA that she transferred between platforms in June. The old platform account peaked at £171,000 before the transfer and the new platform account peaked at £186,000 in November. She also held an old cash ISA with £3,500 in it, which she closed in February.

Current account, bank account type: £9,000, or $11,700 at the assumed rate. Already reported.
Fixed-rate cash ISA, bank account type: £42,000, or $54,600. Omitted.
Stocks and shares ISA at the old platform, securities account type: £171,000, or $222,300. Omitted, and reportable even though it was empty by July.
Stocks and shares ISA at the new platform, securities account type: £186,000, or $241,800. Omitted.
Old cash ISA closed in February, bank account type: £3,500, or $4,550. Omitted, and reportable because it existed during the year.

The FBAR for that year should have listed five accounts, not one. Sarah's year-end position is the cash ISA, the new platform ISA and the current account, roughly £237,000 or $308,100 at the assumed rate, which is above the $200,000 year-end Form 8938 threshold for an unmarried taxpayer living abroad. Her cash ISA interest was never reported, and the stocks and shares ISA holds four UK-domiciled funds, each a likely PFIC needing its own Form 8621. Because income was omitted, Sarah's case is a route two case: three years of amended returns with Forms 8938 and 8621, six years of FBARs rebuilt account by account including the closed ISA and both sides of the transfer, and a Form 14653 certification.

What is the next step if your ISAs were left off?

Start with the account list, not the form. For each of the six most recent FBAR years, list every ISA held at any point, including those closed, matured or transferred, with the provider name and address, the account reference and quarterly valuations, plus the holdings history for any stocks and shares ISA. With that pack the route decision is usually clear at first review. We then prepare the FBARs, any amended returns and the supporting statements together so that account lists, values and explanations agree across every document. A Missed FBAR on an ISA is a fixable compliance gap, best corrected in full, in one coordinated filing, before another year is added to it.