UK TAX SERVICES

You generally must file a Self Assessment return if you are self-employed, a company director, or have untaxed income such as rental, dividend or foreign income. HMRC requires online returns by 31 January following the end of the tax year on 5 April. US persons with UK income often need both a UK return and a US filing.

The UK tax year runs 6 April to 5 April. Paper Self Assessment returns are due by 31 October and online returns by 31 January, which is also the deadline to pay the tax owed. Payments on account may fall due on 31 January and 31 July. Missing a deadline triggers automatic HMRC penalties and interest.

Your UK residence status, determined by the Statutory Residence Test, decides whether you are taxed on worldwide income or only UK income. Residents are generally taxed on worldwide income, while non-residents are taxed only on UK-source income. For those with US ties, residence status also interacts with the US-UK treaty and US worldwide taxation.

From April 2025 the UK abolished the long-standing remittance basis for non-domiciled individuals, replacing it with a residence-based regime for foreign income and gains. New arrivals may receive relief on foreign income for their first years of UK residence. Anyone who previously relied on non-dom status should review their position urgently.

If you are UK resident and taxed on the arising basis, you generally pay UK tax on your worldwide income, including foreign earnings, with foreign tax credits relieving double taxation. Reporting rules changed with the 2025 non-dom reforms. US citizens in the UK must coordinate this with their IRS filing to avoid being taxed twice.

Yes. We are specialist US and UK cross-border accountants, preparing HMRC Self Assessment alongside IRS federal returns. We coordinate residence, treaty positions and foreign tax credits so your UK and US filings work together rather than against each other. Handling both jurisdictions in one place prevents double taxation and keeps you compliant everywhere.