Tax between the UK and the US
Your life touches both the UK and the US, and both want a say in your tax. With a plan for each side, you stay in control of both.
| United States | citizens and residents taxed on worldwide income, including abroad |
| UK-US treaty | saving clause: the US may tax its citizens as if the treaty did not exist, with exceptions |
| Accounts | FBAR when foreign accounts together exceed $10,000 |
| Estates | a separate UK-US estate and gift tax treaty, in force since 11 November 1979 |
| Updated | November 2026 |
Two systems that do not talk to each other
The US taxes citizens and residents on their worldwide income, wherever they live. The UK taxes whoever is resident under the residence test. An American in London or a Dutch green card holder in Edinburgh therefore stands with one foot in each system. The UK-US treaty helps, but it contains a saving clause under which the US keeps the right to tax its citizens as if the treaty did not exist. Add reporting duties such as the FBAR for foreign accounts above $10,000. Everything from the UK side is in US citizens in the UK.
In the other direction, from the UK to the US, it is about leaving the UK cleanly, your pension and ISA under the treaty, and the inheritance tax tail. The UK side is in moving from the UK to the US.
For everything American, from the US tax return to forming a company in the US, our sister firm in Austin is the right address: Mount Bonnell.
The articles on the UK and the US
Frequently asked questions
Do I have to file a US tax return as a US citizen in the UK?
Yes. The US taxes citizens and residents on their worldwide income, even when they live abroad. If you live abroad, you get an automatic two-month extension to 15 June. For the return itself, Mount Bonnell is the right address.
What is the FBAR?
The report of foreign accounts to the US authority FinCEN on Form 114. It is due when your foreign accounts together exceed $10,000 at any point in the year, even if they produce no taxable income. It is due on 15 April, automatically extended to 15 October.
Does the treaty protect me from double tax?
Partly. The saving clause lets the US tax its citizens as if the treaty did not exist. Some articles, for example on pensions and on the credit, still apply to citizens. Which ones is explained in US citizens in the UK.
Is there an estate tax treaty between the UK and the US?
Yes, the treaty on estate and gift taxes has been in force since 11 November 1979. It decides which country may tax assets when both claim them.
The UK and the US, sorted in one conversation
In the UK Tax Consult we settle the UK side, residence, the FIG regime, ISA and pension, and line it up with the US side. By phone, Zoom or Signal.