For US citizens and green card holders living abroad, the obligation to file a US federal tax return does not end at the border. The United States taxes its citizens on worldwide income regardless of where they live or work — making compliant, strategic US tax filing essential for every American expatriate, dual citizen, and non-resident with US-source income.
At a glance — US tax returns for Americans in the UK. We prepare US federal income tax returns (Form 1040) for US citizens and green card holders living in the UK and elsewhere abroad, together with the international forms that usually go with them: FBAR (FinCEN Form 114), FATCA Form 8938, Form 2555 (Foreign Earned Income Exclusion), Form 1116 (Foreign Tax Credit) and, where relevant, Forms 5471, 3520 and 8621.
- Who it is for: Americans and green card holders resident in the UK, UK/US dual citizens, and Americans who have returned to the US with UK income or accounts.
- Key dates: the return is due 15 April; if you live abroad you get an automatic extension to 15 June (interest still runs from 15 April); the FBAR is due 15 April with an automatic extension to 15 October.
- Behind on filing? See our IRS Streamlined Filing service.
- Getting started: send us a short enquiry listing all your sources of income; we confirm the work required and a fixed fee before any engagement.
- Not a US person but receive US income? UK residents use Form W-8BEN rather than a US return in many cases — see our W-8BEN guide for UK residents.
Our dual-qualified team prepares every form the IRS requires, minimises your liability through every available exclusion and credit, and keeps you fully compliant across both the IRS and, where relevant, HMRC frameworks.
Who We Serve
- US citizens living in the UK or abroad — with foreign employment income, self-employment, rental income, investments, or business interests
- Green card holders residing outside the US who retain worldwide filing obligations
- Dual US-UK nationals navigating both the IRS and HMRC simultaneously
- Americans returning to the US after a period abroad
- Non-resident aliens with US-source income requiring Form 1040NR
- Accidental Americans who have only recently become aware of their filing requirements
US Tax Forms We Prepare
Every engagement is bespoke. The forms we prepare depend on your income profile, assets, and circumstances. Core filings typically include:
Federal Income Tax Returns
- Form 1040 — US Individual Income Tax Return (the primary annual filing for US citizens and residents)
- Form 1040NR — US Non-Resident Alien Income Tax Return, for non-residents with US-source income
- Form 2555 — Foreign Earned Income Exclusion, allowing qualifying expats to exclude up to the annual inflation-adjusted threshold from US taxation
- Form 1116 — Foreign Tax Credit, offsetting US tax dollar-for-dollar against foreign income taxes paid
International Disclosure & Compliance Forms
- FinCEN Form 114 (FBAR) — Report of Foreign Bank and Financial Accounts, required when aggregate foreign accounts exceed $10,000 at any point during the year. Filed electronically with FinCEN, separate from the tax return
- Form 8938 — FATCA Statement of Specified Foreign Financial Assets, filed with the tax return when thresholds are exceeded
- Form 3520 & 3520-A — Annual Return regarding foreign trusts and receipt of certain foreign gifts
- Form 5471 — Information Return for US persons with interests in foreign corporations
- Form 8865 — Return of US Persons with respect to certain foreign partnerships
- Form 8621 — Passive Foreign Investment Company (PFIC) reporting, critical for expats holding UK ISAs, unit trusts, or non-US ETFs
- Form 8833 — Treaty-Based Return Position Disclosure, used when claiming US-UK Tax Treaty benefits
- Form 8858 — Information Return for Foreign Disregarded Entities
- Form W-8BEN — Certificate of Foreign Status, for withholding purposes on US-source income
Key Exclusions, Credits, and Planning Tools
Foreign Earned Income Exclusion (FEIE)
Qualifying expats can exclude a substantial portion of foreign-earned wages from US taxation via Form 2555. Eligibility requires passing either the Physical Presence Test (330 full days abroad in a consecutive 12-month period) or the Bona Fide Residence Test. Read our FEIE guide.
Foreign Tax Credit (FTC)
For expats in high-tax countries such as the UK, the Foreign Tax Credit often produces a superior outcome to the FEIE, eliminating US tax liability while preserving access to US retirement account contributions. Unused credits carry forward up to 10 years. Read our FTC guide.
Foreign Housing Exclusion / Deduction
In addition to the FEIE, qualifying expats may also exclude or deduct qualifying foreign housing costs, further reducing US taxable income.
Filing Deadlines
- April 15 — Standard federal tax return due date
- June 15 — Automatic 2-month extension for US citizens and residents living abroad (interest on tax owed still accrues from April 15)
- October 15 — Extended deadline with Form 4868
- April 15 (October 15 automatic extension) — FBAR filing deadline via FinCEN
- December 15 — Additional discretionary extension available on request
Risks & Penalties for Non-Compliance
The penalties for failure to file or late filing can be severe. The IRS has significantly increased enforcement of international compliance in recent years:
- Failure-to-file penalty — 5% of unpaid tax per month, up to 25%
- FBAR non-willful penalty — can apply per year of non-compliance
- FBAR willful penalty — significantly higher, with potential criminal exposure
- Form 5471 / 8938 / 3520 penalties — $10,000 per form per year, increasing with continued non-compliance
- PFIC regime — punitive tax and interest on undisclosed PFIC holdings
If you have missed filings, the IRS Streamlined Filing Compliance Procedures may allow you to catch up with significantly reduced or no penalties.
Our Process
- Discovery call — We review your full income profile, assets, residency history, and any prior filings
- Obligation mapping — We identify every form, disclosure, and deadline that applies to your situation
- Data collection — We provide a secure, structured checklist to gather everything we need
- Preparation & review — Your returns are prepared by a qualified specialist and reviewed for accuracy and optimisation
- Filing & confirmation — We file electronically where possible and provide copies of all filings
- Ongoing compliance — We proactively alert you to legislative changes affecting your situation
How to Start Your US Tax Return With Us
- Send us an enquiry with your country of residence, the tax years involved, your filing history, and all your sources of income in every country — employment, self-employment, rental, investments, pensions and benefits.
- We confirm which returns, forms and years are required and give you a fee quote before any work begins.
- Once you are onboarded (identity checks and a signed engagement letter), we send a tailored document list.
- We prepare your return and supporting forms for your review and signature, and coordinate with your UK Self Assessment where needed.
Prefer to talk it through first? Paid consultations are available from £350 for individuals.
Frequently Asked Questions
Do I have to file a US tax return if I live in the UK?
Yes. US citizens and green card holders are required to file a US federal tax return on their worldwide income regardless of where they live. The US is one of only two countries (along with Eritrea) that taxes based on citizenship rather than residence.
Will I pay tax to both the US and the UK on the same income?
Structured correctly, almost certainly not. The Foreign Tax Credit, the FEIE, and the provisions of the US-UK Tax Treaty are designed to eliminate double taxation. In the majority of cases, expats in the UK owe no additional US tax once these mechanisms are properly applied — but the filing obligation remains.
I have not filed US returns for several years. What should I do?
You are not alone. Many expats discover their filing obligations late. The IRS Streamlined procedures offer a penalty-relief pathway for non-wilful non-compliance. See our Streamlined Filing service or book a confidential consultation.
What is a PFIC and why does it matter?
A Passive Foreign Investment Company includes many non-US mutual funds, ETFs, and investment vehicles — including UK ISAs held in funds. US persons holding PFICs without proper reporting and elections face punitive tax treatment. This is one of the most commonly overlooked compliance areas for UK-based Americans.
Do I need to report my UK bank accounts, ISAs and investments to the IRS?
Usually, yes. UK bank, savings, ISA and investment accounts count towards the FBAR test, which applies when the combined highest balances of all your foreign accounts exceed $10,000 at any time in the year. Separately, Americans living abroad file FATCA Form 8938 when specified foreign financial assets exceed $200,000 on the last day of the year or $300,000 at any time ($400,000 / $600,000 if married filing jointly). An ISA is not tax-free for US purposes — see our UK ISA guide and FBAR requirements.
When is my US tax return due if I live in the UK?
The normal due date is 15 April. US citizens and green card holders living abroad receive an automatic two-month extension to 15 June to file and pay, but interest on unpaid tax runs from 15 April. A further extension to 15 October is available on request. The FBAR is due 15 April with an automatic extension to 15 October.
What do you need from me to give a quote?
Your country of residence, the tax years involved, which US returns and FBARs you have already filed, and a list of all your income sources in every country. We quote only once we have that full picture, so there are no surprises later.
Explore Related Services & Resources
- IRS Streamlined Filing — Catch up on missed returns with reduced penalties
- Cross-Border Tax Planning — Proactive strategy to minimise lifetime tax
- FBAR Filing Guide
- FATCA Reporting Guide
- Student Loan Repayment Calculator
Ready to get compliant and optimise your US tax position? Book a confidential consultation with our specialist team today.