Haven't Filed US Taxes Living in the UK? What to Do Next

Haven't filed US taxes living in the UK? An introduction

If you haven't filed US taxes living in the UK, you can usually put it right without heavy penalties, provided you act before the IRS contacts you. Most Americans in Britain owe little or no US tax, because UK tax is credited against it. However, the missing returns and account reports still matter. Therefore, the aim is to catch up in the right order and with the right certification.

This article sets out why the duty exists, the options in order, and what to gather first. Our full guide to IRS Streamlined Filing from the UK covers the main catch-up route in more depth.

Why so many people haven't filed US taxes living in the UK

The reasons are usually ordinary. Some people moved as children and never knew. Others assumed that paying UK tax through PAYE ended any US duty. Many were born in the United States to British parents and returned to Britain as babies. In our experience, the discovery often comes through a bank letter, a mortgage application or a passport renewal. Consequently, the first feeling is alarm, but the position is rarely as bad as it seems.

Why do Americans in the UK have to file at all?

The United States taxes its citizens and green card holders on worldwide income, wherever they live. That is citizenship-based taxation. The UK also taxes you as a resident, so both countries have a claim on the same income.

The filing duty in plain terms

A US citizen must file a federal return each year if their gross worldwide income reaches the filing threshold for their status. The IRS says so on its page about filing requirements for citizens abroad. The threshold is indexed each year, so check the current table. Notably, a UK salary counts in full, even when all its tax was paid in Britain. Hence, most working adults cross the threshold.

The accidental American

An accidental American is someone who holds US citizenship, often by birth, but has lived elsewhere for most of their life. Many never held a US passport. Nevertheless, US law treats them as citizens from birth, with the same filing duties. US law sets out how citizenship arises at birth in 8 US Code section 1401. If you haven't filed US taxes living in the UK because you never knew you were American, you are in a very common position.

What happens if you have never filed?

For most UK residents, the tax itself is small or nil. The real exposure comes from penalties for missing information returns and FBARs. Furthermore, the IRS can assess tax for an unfiled year at any time, because the limitation period does not start until a return is filed.

Tax owed is often nil

UK income tax rates are generally higher than US rates on the same salary. The foreign tax credit, claimed on Form 1116, lets you set UK tax against US tax on UK income. The IRS explains it on its foreign tax credit page. Alternatively, the foreign earned income exclusion removes salary up to an annual limit. As a result, many late filers end with no US tax due. However, ISA income, UK funds and property sales can still leave something to pay.

Penalties that can apply

A late return with tax due attracts a failure-to-file penalty of 5% of the unpaid tax for each month, capped at 25%. The IRS explains it on its page about the failure-to-file penalty. Where no tax is due, that penalty is nil. In contrast, information return penalties do not depend on tax owed. For example, a missed Form 8938 can attract a $10,000 penalty. FBAR penalties are separate again and are adjusted for inflation.

The open statute of limitations

Normally the IRS has three years from filing to assess more tax. However, that period never begins for a year with no return. Moreover, a missing information return can keep the whole year open, under 26 US Code section 6501. Therefore, unfiled years do not age out on their own. The only way to close them is to file.

Does the IRS already know about your UK accounts?

Very often, yes. UK banks report accounts held by US persons to HMRC, which passes the details to the IRS each year. Therefore, the question is rarely whether the IRS can find out, but whether you act first.

How FATCA reporting works in the UK

FATCA is the US law that requires foreign banks to identify and report accounts held by US persons. The UK applies it through an intergovernmental agreement, published by HMRC as the UK-US automatic exchange of information agreement. Under it, UK banks send account details to HMRC, and HMRC sends them on. The US Treasury describes the framework on its FATCA page. Consequently, people who haven't filed US taxes living in the UK may already appear in IRS data.

Bank letters and self-certification

Many people first learn of the issue through a bank letter asking them to confirm their US status. The bank may ask for a US taxpayer number or a signed form. Answer it honestly and promptly. However, the letter does not mean the IRS has opened a case. In our experience, it is simply the moment to start the catch-up. If you haven't filed US taxes living in the UK, that letter is a useful prompt rather than a crisis.

What are your options, in order?

The right route depends on whether your failure was non-wilful and whether the IRS has already contacted you. For most people who haven't filed US taxes living in the UK, the Streamlined Foreign Offshore Procedures fit. A few cases need a different route.

Option one: Streamlined Foreign Offshore Procedures

The Streamlined Foreign Offshore Procedures are an IRS programme for non-wilful taxpayers who live abroad. You file the most recent three years of returns and the most recent six years of FBARs. You also sign Form 14653, a certification that your failure was non-wilful. The IRS sets out the terms for US taxpayers residing outside the United States. If you qualify and comply, the IRS does not charge failure-to-file, failure-to-pay, information return or FBAR penalties. You pay any tax and interest due with the filings.

Who qualifies

A US citizen qualifies if, in at least one of the last three years, they had no US abode and spent at least 330 full days outside the United States. Most long-term UK residents meet that easily. Additionally, the IRS must not have opened a civil examination of any of your returns. The general rules are on the IRS page for Streamlined Filing Compliance Procedures. Non-wilful conduct is conduct due to negligence, inadvertence, mistake, or a good-faith misunderstanding of the law.

Option two: filing late returns with reasonable cause

Some people have filed tax returns but missed only information forms, such as Form 8938 or Form 5471. They may file the missing forms with a reasonable cause statement under the IRS Delinquent International Information Return Submission Procedures. However, penalties can still be assessed during processing, and you may need to answer IRS letters. Therefore, this route suits narrow gaps, not a history of no returns at all.

Late FBARs on their own

Late FBARs are filed through the FinCEN BSA E-Filing System, with a reason for lateness chosen from a list. FinCEN explains the steps on its page on filing late. The IRS removed its Delinquent FBAR Submission Procedures page in July 2026. Consequently, late FBARs filed outside the Streamlined route carry no stated penalty protection. If you haven't filed US taxes living in the UK either, the Streamlined route is usually the safer way to bring FBARs up to date.

What if the problem was wilful?

The Streamlined route is only for non-wilful conduct. If you knew of the duty and chose not to file, you need a different approach. The certification is signed under penalty of perjury, so it must be true.

The voluntary disclosure route

The IRS Criminal Investigation Voluntary Disclosure Practice is the route for wilful cases. It carries heavier penalties but offers a path to resolve the position. The IRS lists the choices on its page on options for undisclosed foreign financial assets. In those cases, take advice from a US tax lawyer before filing anything. We prepare returns and do not give legal advice on wilfulness.

What should you gather first?

Start with your UK tax records for the last three tax years and your account statements for the last six calendar years. With those, the returns and FBARs can be prepared in one pass.

Your UK records

Collect your P60s, any UK Self Assessment returns, and the tax calculations HMRC issued. These give the UK tax that becomes your foreign tax credit. Similarly, gather pension statements and any ISA or fund statements. Because the UK tax year ends on 5 April, the figures will need splitting into calendar years.

Your account balances

For each year, you need the highest balance of every non-US account. That includes current accounts, savings, ISAs, pensions where they count as accounts, and joint accounts. The IRS explains the rules on its page about the Report of Foreign Bank and Financial Accounts. Moreover, you will need a Social Security number. If you never had one, the SSA page for people outside the United States explains how to apply.

Paying any tax and interest due

Under the Streamlined route, you pay any tax and interest with the filings. Interest runs from each original due date at the rate the IRS sets each quarter, shown on its page of quarterly interest rates. For most people who haven't filed US taxes living in the UK, the amounts are modest because UK tax covers most of the US liability. Nevertheless, the payment must accompany the returns, so plan for it early.

An illustrative example

Consider a typical case. Hannah was born in Boston to British parents and moved to Leeds at the age of two. She is now 41, works as a teacher and has never filed a US return. A letter from her bank asked her to confirm her US status.

Because her failure was non-wilful, Hannah would use the Streamlined Foreign Offshore Procedures. She would file three years of returns, each claiming credit for the UK tax on her salary. She would also file six years of FBARs for her current account, savings and ISA. In this example, the returns show little or no US tax. As a result, Hannah becomes compliant and can then file normally each year.

How US UK Tax Experts can help

We help people who haven't filed US taxes living in the UK to catch up in one organised process. First, we confirm which route fits and which years are needed. Next, we work out the UK figures for those years and convert them to dollars. We then prepare the returns, the FBARs and the Form 14653 narrative for you to review and sign. Finally, we set up the following year so it can be filed on time.

Our Streamlined filing service covers the catch-up, and our FBAR and FATCA service covers the account reports. In addition, our guide to FBAR and FATCA reporting explains the account rules in detail.

Conclusion

In summary, if you haven't filed US taxes living in the UK, you are far from alone, and the tax due is often small. The penalties sit in the missing information returns and FBARs. For non-wilful cases, the Streamlined Foreign Offshore Procedures provide a clear route: three years of returns, six years of FBARs and a signed certification. Therefore, act before the IRS writes to you, and gather your records first. Ultimately, a tidy catch-up turns an open question into a routine annual filing.

Contact us

Have you just discovered that you haven't filed US taxes living in the UK? Email us at hello@usuktaxexperts.com, or describe your situation through our contact page. We reply within one working day with the route that fits and the records to gather.