Does a minor child have to file an FBAR?

Yes. The FBAR rules apply to any United States person and contain no minimum age and no exemption for minors. A US-citizen or resident child whose foreign financial accounts exceeded 10,000 US dollars in aggregate at any time during the calendar year must have an FBAR filed in their name, even if the child has no income and no US income tax return requirement for that year.

Does a UK Junior ISA have to be reported on an FBAR?

Yes, where the child is a US person and the threshold is met. A cash Junior ISA is a foreign deposit account and a stocks and shares Junior ISA is a foreign securities account, and both are reportable. The UK tax-free wrapper has no effect on US reporting, and because Junior ISAs generate no HMRC reporting for the family, they are among the most commonly overlooked accounts.

Does the child need a Social Security Number before we can file?

In practice, yes. The FBAR is filed under the child's own identifying number, and a US citizen cannot use an ITIN. The IRS states that ITINs are only for people not eligible for a Social Security Number and that US citizens should not apply. A US-citizen child born abroad ordinarily obtains an SSN following consular registration of the birth, and that process sets the timetable for the catch-up.

Can we just add the child's accounts to a parent's FBAR?

No. The child files a separate report. The joint filing accommodation using FinCEN Form 114a is written for spouses, not for parent and child. A parent who can direct a child's Junior ISA does report that account on their own FBAR under the signature authority limb, but that is an additional report, not a substitute for the child's, and each person tests their own 10,000 US dollar aggregate.

What happens when the child turns 18 with unfiled FBARs?

Nothing is written off. The young adult inherits the unfiled years and from then on signs their own reports and answers UK banks' US-status questions personally. Junior ISA control passes at sixteen and the funds become accessible at eighteen, which is also when US-reportable income starts. Correcting two or three years while balances are small is far simpler than resolving the same history a decade later.

Missed FBAR on a Child's UK Account: Who Files

Q: Who signs the FBAR if the child is too young to sign?

FinCEN's guidance states that a child is generally responsible for filing their own FBAR, but if the child cannot file for any reason, including age, a parent, guardian or other legally responsible person must file it for them. The parent signs electronically on the child's report and enters Parent/Guardian filing for child in the filer title field. The report itself remains in the child's name.

A missed FBAR on a child's UK account is the child's own compliance problem rather than the parent's, and that single fact governs everything that follows: the report is filed in the child's name, under the child's own identifying number, measured against the child's own 10,000 US dollar aggregate, and signed electronically by a parent or guardian only because the child cannot sign it. There is no minimum age in the FBAR rules and no exemption for minors. If a child is a US citizen or resident and had a financial interest in, or signature authority over, foreign financial accounts whose combined value exceeded 10,000 US dollars at any point in the calendar year, an FBAR was due for that child, filed separately from every other family member's report.

In the returns we prepare for US-connected families in the UK, this is one of the most common late-discovered gaps, and almost never a deliberate one. A Junior ISA opened by a British parent for a child who happens to be a US citizen through the other parent looks, to everyone in the family, like an ordinary UK savings product. It attracts no HMRC reporting, no UK tax return, and no correspondence that would prompt anyone to think about the United States. The failure surfaces years later, usually when the parent starts their own catch-up filing, when a UK bank asks the child for a self-certification of tax residence, or when an eighteen-year-old tries to open an account and is asked whether they were born in, or hold citizenship of, the United States.

Does a US-citizen child really have to file an FBAR?

Yes. The FBAR obligation attaches to a United States person, and a United States person is defined by citizenship or residence, not by age, income, capacity or whether an income tax return is required. The IRS sets out the filing rule at https://www.irs.gov/businesses/small-businesses-self-employed/report-of-foreign-bank-and-financial-accounts-fbar and states plainly that a US person must file if they have a financial interest in or signature or other authority over at least one financial account located outside the United States and the aggregate value of all foreign financial accounts exceeded 10,000 US dollars at any time during the calendar year reported. Nothing in that test carves out children.

The practical consequence is uncomfortable but simple. A newborn US citizen with a UK bank account funded by a grandparent's gift can have an FBAR obligation before their first birthday. The threshold is an aggregate, tested at the highest point in the year, not at 31 December, so an account that received a lump sum in March and was spent down by December can still trigger a report. And the threshold is not a per-account figure: it is the combined maximum of every foreign account the child holds or controls.

Two points matter before any of this is assumed. First, confirm the child actually is a US citizen. Citizenship at birth outside the United States to a US-citizen parent depends on the parent's own status and their prior physical presence in the United States, and it is not automatic in every case. Second, confirm the aggregate. In many families with young children the accounts are small enough that no FBAR was ever due, and the correct answer to a worried parent is that there is nothing to file for the earlier years and only a forward-looking watching brief on the balance.

Who signs a child's FBAR, and whose name goes on the report

FinCEN addresses this directly in its guidance for filing on behalf of a child at https://www.fincen.gov/filing-child. Generally, a child is responsible for filing their own FBAR. If a child cannot file for any reason, including age, the child's parent, guardian or other legally responsible person must file it for the child. If the child cannot sign the report, a parent or guardian must sign it electronically, and in the filer title field the signer enters the description Parent/Guardian filing for child. The IRS repeats the same rule in its plain-language summary at https://www.irs.gov/newsroom/details-on-reporting-foreign-bank-and-financial-accounts.

That mechanism is a signature accommodation, not a transfer of the obligation. The report remains the child's report throughout. In practice this means:

The filer named on the FBAR is the child, with the child's date of birth and the child's own taxpayer identifying number, not the parent's.
The child's accounts are never merged into a parent's FBAR as though they were the parent's own accounts; a separate report is filed for the child.
The parent's role appears only in the signature block and the filer title description Parent/Guardian filing for child.
The joint filing accommodation described on the IRS FBAR page is written for spouses using FinCEN Form 114a, and there is no equivalent that lets a parent fold a child's accounts into their own return of foreign accounts.
One FBAR per child per year is required, so a family with three US-citizen children over the threshold files three separate reports, plus each parent's own report where required.
The five-year record retention rule applies to the child's records in the same way it applies to an adult's, and in practice the parent keeps them.

Where an older teenager can sign for themselves, they should. A sixteen or seventeen-year-old who understands what they are signing can hold their own BSA E-Filing credentials, and doing so avoids any later argument about whether a signature was properly authorised. We generally move signing responsibility to the child at the point they take control of a Junior ISA, which under UK rules happens at sixteen.

How a Junior ISA or UK child savings account fits the definition

A Junior ISA is a foreign financial account for FBAR purposes. GOV.UK describes the product at https://www.gov.uk/junior-individual-savings-accounts: a parent or guardian with parental responsibility opens the account, the money in it belongs to the child, the annual allowance is 9,000 pounds for the 2026 to 2027 tax year, the child takes control of the account at sixteen, and the money cannot be withdrawn until the child turns eighteen. Both varieties count. A cash Junior ISA is a deposit account at a UK financial institution. A stocks and shares Junior ISA is a securities account, and securities accounts held outside the United States are reportable in exactly the same way as bank accounts.

The ISA wrapper is a UK tax concept with no US counterpart. It removes UK income tax and capital gains tax on the return, which is why the family sees no HMRC paperwork, but it does nothing at all to the US position. GOV.UK confirms at https://www.gov.uk/savings-for-children that the well-known 100 pound rule, under which a parent must tell HMRC if interest on money they gave the child exceeds 100 pounds in a tax year, does not apply to Junior ISAs. That is precisely why these accounts sit unexamined for a decade: they generate no UK reporting trigger of any kind.

Ordinary UK child savings accounts, building society accounts, Child Trust Funds that were never transferred, credit-union junior accounts and app-based children's accounts are all foreign financial accounts on the same test. So is a UK account in the child's name that a grandparent controls. The question the FBAR asks is where the account is maintained and what interest the US person has in it, not what the account is called or how the UK taxes it.

Financial interest versus signature authority: the parent's side of the same account

The two limbs of the FBAR test do different work, and on a child's account they often both bite at once. A US person has a financial interest in an account where they are the owner of record, and also where the owner of record or holder of legal title is a person acting as an agent, nominee, attorney or in some other capacity on their behalf. A US person has signature or other authority where they can control the disposition of the money in the account by direct communication with the institution that maintains it, whether alone or together with someone else. The IRS sets both definitions out in Publication 5569, the FBAR reference guide, at https://www.irs.gov/pub/irs-pdf/p5569.pdf.

Apply that to a Junior ISA. The money belongs to the child, so the child has the financial interest, even though the parent is the registered contact and the child cannot touch the funds. The parent, as registered contact, can typically switch providers, change investment selections and direct the account, which is the kind of control that meets the signature-authority definition. Both the child and the parent can therefore have a reportable relationship with a single account, and each tests it against their own separate 10,000 US dollar aggregate. The parent reports it in the part of the form used for accounts over which the filer has signature authority but no financial interest; the child reports it as an owned account.

This is where families get the arithmetic wrong in both directions. A parent will often assume that because the child's balance is small, nothing is reportable anywhere, forgetting that the child's account is added to the parent's own aggregate through the signature-authority limb. Or a parent assumes that because they crossed the threshold and reported everything, the child is covered, which is not how separate reports work. Each US person in the household runs their own aggregation. Nothing is netted across the family.

A worked example, using illustrative figures

The following figures are an illustration and the exchange rate is an assumption, not a published rate. Take a London family with a British father and a US-citizen mother, and two children who are US citizens from birth. The elder child, aged fourteen, has a cash Junior ISA that peaked at 24,000 pounds during the calendar year and a high-street child savings account that peaked at 3,000 pounds. The younger child, aged seven, has a Junior ISA that peaked at 5,500 pounds and nothing else. The mother is the registered contact on both Junior ISAs. Assume for illustration a conversion of 1.30 US dollars to the pound; a real filing must use the Treasury reporting rate of exchange for 31 December of the year being reported.

Elder child: 27,000 pounds aggregate, roughly 35,100 US dollars on the assumed rate. Over the threshold, so an FBAR is due in the elder child's name reporting both accounts, signed by a parent.
Younger child: 5,500 pounds aggregate, roughly 7,150 US dollars. Under the threshold, so no FBAR is due for the younger child, and the elder child's balances are not added to that test.
Mother: her own accounts, plus both Junior ISAs over which she has signature authority, are aggregated on her single report, which takes her over the threshold even ignoring her own balances.
Father: not a US person, so no report, and his sole-name accounts are outside the children's tests entirely unless a child is named on them.
Result for one year: two FBARs, not one, not three, and the elder child's report is the one nobody in the family knew existed.

Run that pattern back six years and the shape of a typical catch-up appears. The elder child usually crosses the threshold at some point in the middle of the period, as gift contributions accumulate, and owes reports only from that year forward. The younger child often owes nothing at all. The parent owes reports for every year. Establishing which years actually breached the threshold, rather than filing defensively for every year, is the first piece of real work.

The accidental-American child problem in the UK

The families we see most often are not evading anything. They are UK-resident households where one parent is American, the children were born in a British hospital, and everyone's financial life is entirely domestic. The child has a Junior ISA opened by a grandparent, a savings account for birthday money, and no connection to the United States beyond a passport that may never have been issued. Nobody ever formed an intention about US reporting because nobody ever framed the question.

What changes the picture is automatic information exchange. UK financial institutions identify and report accounts held by US persons under the FATCA framework, which the IRS summarises at https://www.irs.gov/businesses/corporations/summary-of-fatca-reporting-for-us-taxpayers. Indicators such as a US place of birth, a US address or a US telephone number on the account record can prompt a UK provider to ask for a self-certification, and a Junior ISA that was opened years earlier with no US indicators can be swept into that process when the provider refreshes its records or when the account is transferred. The failure mode we see most often is a letter from a UK provider addressed to a teenager, asking a question the parents cannot answer without disclosing a decade of unreported accounts.

The right response is to establish facts before filing anything: whether the child is in fact a US citizen, which accounts existed in which years, what each peaked at, and which years actually exceeded 10,000 US dollars. A defensive filing of every year for every child, without that groundwork, creates a paper record of reports that may not have been required and does nothing to reduce risk.

Does the child need a Social Security Number before anything can be filed?

This is the practical bottleneck, and it is the point at which most accidental-American-child catch-ups stall. The FBAR is filed in the child's name and asks for the child's identifying number. A US citizen cannot solve that with an ITIN. The IRS is explicit at https://www.irs.gov/individuals/international-taxpayers/individual-taxpayer-identification-number that an ITIN is for people who have a federal tax purpose and are not eligible for a Social Security Number, that anyone eligible for an SSN does not need one, and that US citizens are on the list of people who should not apply. A US-citizen child needs an SSN, which for a child born abroad ordinarily follows registration of the birth with a US consulate.

That has real consequences for sequencing. If the plan is a catch-up under the Streamlined Filing Compliance Procedures, the IRS states at https://www.irs.gov/individuals/international-taxpayers/streamlined-filing-compliance-procedures that all returns submitted must have a valid taxpayer identification number, that for most individuals this means a valid Social Security Number, and that a submission without one will not be processed. There is an accommodation allowing a submission accompanied by a complete ITIN application, but that route is closed to a US citizen who is not eligible for an ITIN in the first place. In other words, the consular and SSN process has to start first, and its timing sets the timetable for everything downstream.

There is one important relief in the sequence. In many of these cases the child has no US income tax return requirement at all, because a child with modest interest income and no earnings falls below the filing thresholds. Where that is the case, the streamlined procedures, which are built around submitting three years of income tax returns together with six years of FBARs and a certification of non-wilful conduct on Form 14653, have nothing to attach to for the child. The IRS describes that package for taxpayers abroad at https://www.irs.gov/individuals/international-taxpayers/u-s-taxpayers-residing-outside-the-united-states. The child's exposure is FBAR-only, and it is corrected through FinCEN's system rather than through a streamlined package. The parent may still need the full streamlined submission for themselves.

Catching up a missed FBAR for a child through the BSA E-Filing System

Late FBARs are filed electronically through FinCEN's BSA E-Filing System, for each affected year, using the form for that year. The system asks the filer to select a reason for filing late, and offers a free-text option where the standard reasons do not fit. The IRS confirms the position at https://www.irs.gov/newsroom/details-on-reporting-foreign-bank-and-financial-accounts: file the late report as soon as possible, explain the delay, and the IRS will not penalise a taxpayer who properly reports the account on a late-filed FBAR where the IRS finds reasonable cause for the late filing. Note that the IRS withdrew its separate delinquent FBAR submission procedures page in 2026, so late FBARs are simply filed through the BSA system with a reason given, or as part of a streamlined submission.

The mechanics for a child's catch-up run in this order:

Confirm the child's US person status and obtain the Social Security Number if one does not yet exist, because nothing can be filed without it.
Build a year-by-year schedule of every UK account in the child's name, including closed accounts and any Child Trust Fund that was later transferred, with the maximum value in each calendar year.
Convert each maximum using the Treasury reporting rate of exchange for 31 December of the relevant year, and identify only the years where the aggregate exceeded 10,000 US dollars.
File one FBAR per breach year in the child's name, with a parent signing electronically and entering Parent/Guardian filing for child as the filer title.
Give a truthful, specific reason for late filing, tied to the child's actual circumstances rather than boilerplate about the parent's own affairs.
Check whether Form 8938 is also in point, remembering that the IRS states at https://www.irs.gov/businesses/corporations/basic-questions-and-answers-on-form-8938 that taxpayers not required to file an income tax return are not required to file Form 8938.
Retain the account records for five years, since the child will need them long after the parent has stopped thinking about it.

Do not assume the six-year FBAR look-back that applies inside a streamlined submission automatically defines the child's exposure. Six years is the streamlined package requirement. Outside that package the correct number of years is the number of years in which the child's aggregate actually exceeded the threshold, which for a child is often two or three rather than six.

How big is the exposure, really?

Smaller than most parents fear, provided the correction is voluntary and the facts are non-wilful. The IRS sets out the statutory penalty structure at https://www.irs.gov/businesses/comparison-of-form-8938-and-fbar-requirements: up to 10,000 US dollars for a non-wilful failure, and for a wilful failure the greater of 100,000 US dollars or 50 percent of the account balances, with the possibility of criminal penalties. Those statutory figures are subject to inflation adjustment, so the applicable maximum in a given year is not the raw number in the statute.

Three things usually keep a child's case at the mild end of that range. The Supreme Court held in Bittner v. United States in 2023 that the non-wilful penalty applies per report rather than per unreported account, which matters for a child holding several small accounts. Reasonable cause relief is expressly contemplated for late-filed FBARs where the account is properly reported. And wilfulness is very difficult to establish against a person who was a minor throughout the period in question, which is a genuinely favourable feature of the child's position that does not exist for the parent.

What happens when the child turns eighteen?

The compliance history does not reset. An eighteen-year-old inherits their own unfiled years, and from that point forward they are an adult US person who signs their own reports, deals with their own correspondence, and answers a bank's self-certification questions personally. The UK product mechanics accelerate the collision: control of a Junior ISA passes to the child at sixteen, the funds become accessible at eighteen, and the account converts into an adult ISA. The moment the young adult can withdraw and reinvest, they start generating US-reportable income and, if they buy UK funds, potentially the passive foreign investment company reporting that comes with non-US collective investments.

That is also the age at which the practical costs land. Unresolved FBAR years sit behind every subsequent application: a US passport, a student account, a first employer's payroll onboarding, a mortgage, any future decision about renouncing citizenship. Renunciation does not erase a prior non-compliance history, and the certifications involved in leaving the US tax system cleanly assume the earlier years are in order. Fixing two or three FBAR years while the child is fifteen and the balances are four figures is a short exercise. The same fix at twenty-five, with an adult ISA, a workplace pension and a first property in the picture, is not.

Our standard approach with these families is to resolve the child's position at the same time as the parent's, in a single co-ordinated exercise. The record-gathering overlaps almost completely, the exchange rate work is identical, the reason for late filing is genuinely the same story told from two angles, and the child's file is closed before the child is old enough to have to explain it themselves. If a missed FBAR on a child's UK account has just surfaced in your household, the first two steps are to confirm citizenship and to establish which years actually breached the threshold. Very often the answer is fewer years, and far less exposure, than the initial panic suggests.