Figures relate to tax year 2025 (US) · 2025-26 (UK)
Of everything an American in the UK has to file, the FBAR is the one most likely to be missed and the one with the most disproportionate consequences. It raises no tax. It costs nothing to submit. And the penalty schedule behind it is the most aggressive most people will ever encounter.
The threshold is balance, not income
You file if the aggregate of your foreign financial accounts exceeded $10,000 at any point during the calendar year. Three details in that sentence do the damage: aggregate, any point, and balance.
Aggregate means you add every account together — current, savings, an old ISA, a pension, an account you hold jointly, an account you merely have signature authority over for an employer or elderly parent. Any point means the highest balance during the year, not the year-end figure; money that landed briefly and left still counts. And balance, not income, means a dormant account holding £9,000 that earned nothing at all is still part of the calculation.
A UK current account, a savings pot and a workplace pension can clear $10,000 between them without any single one looking significant.
| FBAR (FinCEN 114) | Form 8938 (FATCA) | |
|---|---|---|
| Filed with | FinCEN, online, separate from the tax return | The IRS, attached to Form 1040 |
| Trigger | Aggregate foreign accounts over $10,000 at any point in the year | Higher thresholds that depend on residence and filing status |
| What it covers | Financial accounts — bank, savings, pensions, signature authority | A broader set of specified foreign financial assets |
| If you skip it | Penalties per violation, even when no tax was due | A fixed penalty per form, plus accuracy exposure |
Deadlines are generous — use them
The FBAR is due 15 April, with an automatic extension to 15 October that requires no request and no form. You do not need to ask, and you cannot be refused. If your accounts are complete only in the autumn, that is what the extension is for.
It is filed electronically with FinCEN, not the IRS, and it is not attached to your tax return. Extending your 1040 does not extend the FBAR — although in practice both now land on the same October date.
What the penalties actually are
- Non-wilful: up to around $10,000 per violation, inflation-adjusted — and the Supreme Court confirmed in 2023 that this applies per report, not per account, which was a significant relief.
- Wilful: the greater of roughly $100,000 or 50% of the account balance, per year — a figure that can exceed the account itself over several years.
- Reasonable cause: a genuine defence where the failure was not negligent, but it must be argued rather than assumed.
The gap between non-wilful and wilful is the whole ballgame, and it turns on facts and conduct rather than intent as most people understand it. Ticking 'no' on a tax return question about foreign accounts while holding several is the kind of fact that argues badly later.
If you have missed years
Do not quietly file six years of late FBARs and hope. Where tax returns were also missed, the Streamlined Foreign Offshore Procedures cover both and waive the penalties. Where the returns were filed correctly and only the FBARs were missed, the delinquent FBAR submission procedures allow late filing with a reason statement, generally without penalty.
Choosing the right route matters more than speed. Filing into the wrong programme forfeits protections that were available in the other.
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Tell us what you hold across the US and UK. We come back with the scope and a fixed fee in writing, at no cost.
Get in TouchPrimary sources
Official guidance from the IRS, FinCEN and GOV.UK. Thresholds and rates on those pages are updated annually — check the current tax year before relying on a figure.
