Tax Specialists for US Expats: Filing FBAR and FATCA the Right Way

Every American living abroad carries a tax obligation that most other nationalities never face. The United States taxes its citizens on worldwide income, regardless of where they live, work, or pay local taxes. For the hundreds of thousands of US citizens residing in the United Kingdom, this creates a filing requirement that runs parallel to their UK obligations — and that most local accountants are wholly unprepared to handle.

Tax specialists for US expats exist because the FBAR and FATCA reporting regimes are not simply additional paperwork. They are legal obligations backed by some of the most severe civil and criminal penalty structures in international tax law. Missing a filing deadline, underreporting a foreign account balance, or failing to disclose a financial interest can result in penalties that dwarf the value of the assets involved.

This guide is written for US citizens and green card holders living in the United Kingdom who want to understand their FBAR and FATCA obligations clearly, appreciate the genuine risks of non-compliance, and know what to look for when selecting an adviser who can manage these obligations correctly. Whether you have been living in the UK for two years or twenty, this information is directly relevant to your financial and legal position.

Understanding Why US Expats Face Dual Tax Obligations

The Citizenship-Based Taxation System

The United States operates a citizenship-based taxation system — one shared only with Eritrea among the world's nations. Every US citizen, regardless of where they reside, must file a federal income tax return with the Internal Revenue Service every year. This obligation does not disappear when you move to London, Edinburgh, or anywhere else in the UK. It follows you, and it must be met alongside your UK tax obligations to HMRC.

The IRS publishes comprehensive guidance for US taxpayers living abroad at: https://www.irs.gov/individuals/international-taxpayers

This dual filing requirement creates a landscape in which a US expat in the UK must simultaneously satisfy HMRC regarding their UK income, capital gains, and residence status while satisfying the IRS regarding their worldwide income, foreign bank account balances, and international financial interests. Without tax specialists for US expats who manage both obligations in a coordinated way, the risk of error — and the consequences that follow — is significant.

How HMRC and the IRS Exchange Information

One of the most important developments in international tax compliance over the last decade has been the automatic exchange of financial information between tax authorities. HMRC and the IRS now share data on US persons with UK financial accounts under the terms of the UK-US Intergovernmental Agreement, which implements FATCA at an international level.

This means that if you are a US citizen with UK bank accounts, investment accounts, or pension arrangements, HMRC is already reporting information about those accounts to the IRS. The assumption that foreign accounts are invisible to the IRS is not just incorrect — it is dangerous. The infrastructure for information sharing is established, operational, and expanding. Tax specialists for US expats understand this reality and structure their clients' compliance accordingly.

Full details of HMRC's approach to international tax compliance and information exchange are available here: https://www.gov.uk/government/organisations/hm-revenue-customs

What Is FBAR and Who Must File It

The Legal Basis for FBAR Reporting

FBAR stands for the Report of Foreign Bank and Financial Accounts. It is filed not with the IRS but with the Financial Crimes Enforcement Network, a bureau of the US Department of the Treasury. The legal basis for FBAR reporting comes from the Bank Secrecy Act, which requires US persons to report foreign financial accounts when the aggregate value of those accounts exceeds $10,000 at any point during the calendar year.

For a US citizen living in the UK, this threshold is almost universally crossed. A standard UK current account, a savings account, an ISA, and a workplace pension can together push an individual well above the $10,000 mark, triggering a mandatory FBAR filing obligation. The filing deadline is 15 April each year, with an automatic extension to 15 October.

The IRS provides detailed FBAR filing guidance here: https://www.irs.gov/businesses/small-businesses-self-employed/report-of-foreign-bank-and-financial-accounts-fbar.

What Counts as a Reportable Account

The definition of a reportable foreign account is broader than most US expats initially expect. It includes bank accounts, savings accounts, securities accounts, mutual funds, insurance policies with a cash surrender value, and any account in which a US person holds a financial interest or over which they have signature authority. This means that a US expat who is a signatory on a UK business account — even one they do not personally own — may have an FBAR filing obligation for that account.

Tax specialists for US expats conduct a thorough review of every financial account and interest their clients hold to ensure that all reportable accounts are identified and disclosed. Missing an account — even inadvertently — can constitute a violation with serious consequences.

The Penalty Regime for FBAR Non-Compliance

The FBAR penalty structure is one of the most severe in US tax law. For non-wilful violations — where the failure to file was not intentional — the IRS can impose a penalty of up to $10,000 per account per year. For wilful violations, the penalty can reach the greater of $100,000 or 50% of the account balance per violation per year. In addition, wilful FBAR violations can carry criminal penalties, including imprisonment.

Many US expats who have never filed an FBAR are not wilful non-compliers — they simply did not know the obligation existed. The IRS offers voluntary disclosure programmes that allow non-compliant taxpayers to come forward and regularise their position, subject to reduced penalties. The Streamlined Foreign Offshore Procedures are specifically designed for US persons residing outside the United States. Details are available here: https://www.irs.gov/individuals/international-taxpayers/streamlined-filing-compliance-procedures

Acting promptly is always better than waiting. The longer a non-compliance position persists, the more years of violation accumulate, and the higher the potential penalty exposure.

What Is FATCA and How Does It Affect US Expats in the UK

The Foreign Account Tax Compliance Act Explained

FATCA — the Foreign Account Tax Compliance Act — was enacted in 2010 and took full effect in 2014. Its primary purpose is to prevent US persons from concealing assets and income in foreign financial accounts. It operates through two mechanisms: first, by requiring US persons to report their foreign financial assets directly to the IRS on Form 8938; and second, by requiring foreign financial institutions — including UK banks, investment firms, and insurers — to report information about US account holders to their local tax authority, which then shares it with the IRS.

FATCA reporting thresholds for US persons living abroad are higher than those for US residents. Single filers living abroad must file Form 8938 if their foreign financial assets exceed $200,000 on the last day of the tax year or $300,000 at any point during the year. For married couples filing jointly, the thresholds are $400,000 and $600,000, respectively.

The IRS publishes its complete FATCA guidance here: https://www.irs.gov/businesses/corporations/foreign-account-tax-compliance-act-fatca.

The Difference Between FBAR and FATCA

FBAR and FATCA are separate obligations with different filing mechanisms, different thresholds, and different definitions of reportable assets. FBAR covers foreign financial accounts and is filed with FinCEN. FATCA covers a broader range of foreign financial assets — including foreign stocks, partnership interests, and certain foreign trusts — and is filed with the IRS as part of the annual tax return on Form 8938.

Critically, satisfying one obligation does not satisfy the other. A US expat with UK accounts and investments may be required to file both an FBAR and a Form 8938, disclosing some of the same accounts on both forms while also disclosing additional assets that appear only on one. The overlap between the two regimes and the differences in what each requires are among the most common sources of error for US expats who attempt to manage their own compliance without specialist support.

Tax specialists for US expats understand the precise scope of each obligation and ensure that both are satisfied correctly and completely every year.

UK-Specific Assets That Create FATCA Complexity

Certain UK financial products and structures create particular FATCA complexity for US expats. Individual Savings Accounts — ISAs — are tax-free under UK law but are not recognised as tax-advantaged accounts by the IRS. Income and gains accumulated within an ISA must still be reported on a US tax return and are fully taxable for US purposes. UK collective investment funds, unit trusts, and OEICs are frequently classified as Passive Foreign Investment Companies under US tax law, which triggers a highly punitive US tax regime unless proper annual elections are made.

UK workplace pension schemes present their own challenges. While the US–UK Double Taxation Convention provides some treaty protection for pension income, the interaction between UK pension tax relief and US tax treatment is nuanced and requires specific expertise to manage correctly. The official treaty is published here: https://www.gov.uk/government/publications/usa-tax-treaties

A US expat who holds any of these assets — ISAs, collective funds, or UK pension schemes — without proper specialist guidance is almost certainly not managing their US tax position correctly, regardless of how diligently they file their UK returns with HMRC.

The Risks of Managing FBAR and FATCA Without Specialist Help

Why General Accountants Cannot Fill This Gap

FBAR and FATCA compliance are not areas where a generalist accountant — whether UK- or US-based — can provide adequate support. A UK accountant with no IRS training will not know that your ISA generates US taxable income or that your unit trust may be a PFIC. A US-based generalist CPA who does not understand UK-source income rules will not advise you correctly on how to claim foreign tax credits that reduce your US liability.

The Institute of Chartered Accountants in England and Wales sets standards for UK practitioners, but FBAR and FATCA expertise falls outside the scope of standard UK accountancy training: https://www.icaew.com.

Only tax specialists for US expats who work in this space every day hold the combination of IRS technical knowledge, UK tax understanding, and practical experience with foreign account reporting that these obligations demand.

The Growing Risk of IRS Enforcement Action

The IRS has significantly increased its enforcement activity in international tax compliance over the last several years. The agency has dedicated substantial resources to identifying US persons with unreported foreign accounts and undisclosed foreign financial assets. The automatic exchange of information under FATCA means that the IRS now receives data directly from UK financial institutions — data that it cross-references against filed tax returns and FBAR submissions.

The Financial Reporting Council, which governs UK financial services standards, reinforces the importance of transparent reporting and compliance: https://www.frc.org.uk.

US expats who have not been filing correctly should not assume that they have gone unnoticed. The information exchange infrastructure is mature, the IRS has the data, and enforcement activity is increasing. Voluntary disclosure remains available — but only before the IRS initiates contact. Once an enquiry or audit begins, the voluntary disclosure window closes.

The Cost of Doing Nothing

Many US expats in the UK have never filed an FBAR, never reported their ISA income on a US return, and never disclosed their UK pension to the IRS. The cost of doing nothing accumulates silently over years — in the form of mounting penalty exposure, accruing interest on underpaid tax, and an increasingly complex rectification challenge.

The OECD's framework for international tax transparency underpins the information-sharing agreements that make non-disclosure increasingly risky: https://www.oecd.org/en/topics/sub-issues/model-tax-convention.html.

The Bank of England's regulatory environment also reinforces the transparency expectations placed on UK financial institutions: https://www.bankofengland.co....

Addressing non-compliance through the correct voluntary disclosure channels — with specialist guidance — is always less costly than waiting for the IRS to act first. The Streamlined Foreign Offshore Procedures exist precisely to give non-compliant expats a structured path back to compliance, and tax specialists for US expats manage this process with precision and discretion.

What to Look for When Choosing Tax Specialists for US Expats

Proven Technical Depth Across Both Systems

Genuine tax specialists for US expats must demonstrate technical competence across both US and UK tax law. Ask specifically whether the firm prepares Form 1040, Form 8938, and FBAR submissions as a regular part of their practice — not as an occasional service. Ask whether they understand PFIC rules, the foreign earned income exclusion under Section 911, and the foreign tax credit mechanism under Section 901. These are the technical foundations of US expat tax compliance, and a firm that cannot discuss them with confidence is not equipped for this work.

Verify UK credentials through ICAEW at: https://www.icaew.com

Verify company registration status and legal standing through Companies House at: https://www.companieshouse.gov.uk

A Clear and Transparent Service Proposition

The best specialist firms for US expat tax work offer clear engagement letters, a defined scope of service, and transparent fee structures before any work begins. They communicate proactively when filing deadlines approach, when IRS guidance changes, or when a client's circumstances create a new compliance obligation. They do not wait for clients to ask the right questions — they anticipate those questions and answer them before they arise.

US and UK operates on exactly this basis. Every client engagement is structured around clarity, proactive communication, and a genuine commitment to managing the full scope of the client's US and UK obligations — not just the most straightforward parts.

How US and UK Helps US Expats Stay Fully Compliant

US and UK provides dedicated tax specialists for US expats who manage FBAR and FATCA compliance as part of a fully integrated UK–US tax service. The firm handles annual FBAR submissions, Form 8938 filings, US federal tax returns, UK self-assessment returns, and the full range of international information reporting obligations that US expats face in the UK.

For clients who have not been filing correctly, US and UK manages the voluntary disclosure process — including Streamlined Foreign Offshore Procedure submissions — with the technical precision and discretion that this sensitive work requires. The firm identifies the full scope of the non-compliance, prepares the necessary filings, calculates the correct penalty exposure, and guides clients through the process of regularising their position with the IRS.

The combination of deep IRS technical knowledge and hands-on HMRC expertise makes US and UK one of the most capable firms in the UK for US expat tax work. Every client receives advice that accounts for both jurisdictionscompletely —without gaps, assumptions, or loose ends.

Get Your FBAR and FATCA Compliance Right With US and UK

If you are a US citizen or green card holder living in the United Kingdom and you are not certain that your FBAR and FATCA obligations are fully met, now is the time to act. The penalty exposure for non-compliance is real, the IRS enforcement environment is active, and the voluntary disclosure window that allows you to regularise your position on the most favourable terms is available only while you act first.

US and UK provides specialist tax services for US expats, giving US citizens in the UK the confidence that every obligation is identified, every filing is accurate, and every planning opportunity is captured — across both the US and UK tax systems.

Email: hello@us-uktax.com Call: 0333 880 7974

Arrange your consultation today. Our team will conduct a full review of your US and UK tax position, assess your FBAR and FATCA compliance history, and deliver a clear, actionable plan to bring you into full compliance and keep you there.

FAQs

Who is required to file an FBAR as a US expat in the UK?

 Any US citizen, green card holder, or other US person who has a financial interest in or signature authority over foreign financial accounts with an aggregate value exceeding $10,000 at any point during the calendar year must file an FBAR. For most US expats living in the UK, standard current accounts, savings accounts, and investment accounts will push them above this threshold. The filing deadline is 15 April, with an automatic extension to 15 October.

What is the difference between FBAR and FATCA for US expats? 

FBAR requires US persons to report foreign financial accounts to the Financial Crimes Enforcement Network when the aggregate balance exceeds $10,000. FATCA requires US persons to report a broader range of foreign financial assets — including stocks, partnership interests, and foreign trusts — to the IRS on Form 8938 when values exceed specified thresholds. Both are separate legal obligations, and satisfying one does not satisfy the other. Many US expats in the UK must file both every year.

What happens if a US expat has never filed an FBAR? 

A US expat who has never filed an FBAR may be eligible for the IRS Streamlined Foreign Offshore Procedures, which allow non-compliant taxpayers residing outside the US to regularise their position by filing three years of amended or delinquent tax returns and six years of FBAR submissions, with a significantly reduced penalty regime. Acting before the IRS initiates contact is essential — once an enquiry begins, the streamlined programme is no longer available.

Are UK ISAs reportable under FBAR and FATCA?

 Yes. UK Individual Savings Accounts are foreign financial accounts for FBAR purposes and foreign financial assets for FATCA purposes. They must be reported on both filings where the relevant thresholds are met. Additionally, income and gains accumulated within an ISA are not tax-free for US purposes — they must be reported on the annual US federal tax return and are fully subject to US income tax, despite being tax-free under UK law.

Can US and UK help with back-filing and voluntary disclosure for US expats? 

Yes. US and UK manages the full voluntary disclosure process for US expats who have not been filing FBAR or FATCA returns correctly. The firm assesses the full scope of the non-compliance, prepares the required submissions, and guides clients through the Streamlined Foreign Offshore Procedures or other applicable IRS voluntary disclosure programmes.

Does holding a UK pension affect my US tax filing obligations? 

Yes. UK workplace pensions and self-invested personal pensions create specific US tax reporting obligations that many US expats are unaware of. While the US–UK Double Taxation Convention provides some treaty protection for pension income in retirement, the annual treatment of pension contributions, employer contributions, and investment growth within the pension requires careful management. Specialist advice is essential for any US expat who holds or contributes to a UK pension scheme.