If you’re a sole trader, a non-resident landlord, or an overseas individual with UK-source income, understanding how Self Assessment works is crucial. This page gives you a simple summary of everything you need to know, with links to more detailed guidance depending on your circumstances.
The UK tax system works differently from many other countries. You, as the taxpayer, are responsible for:
HMRC does not usually calculate or confirm your final tax bill for you. If you file late or pay late, you will be penalised—even if you don’t owe much (or any) tax.
We’re here to make this process easier. We specialise in helping overseas individuals navigate the UK Self Assessment system with clear, accurate, and timely tax filings.
You’ll need to register for and submit a Self Assessment tax return if you are:
We will guide you through whether you need to register, and help you stay fully compliant.
If you have other types of UK income in addition to your self-employment or rental income, they must be included in separate sections of the tax return. We will ensure each type of income is correctly reported.
Examples include:
If you are UK tax resident, you must also report your worldwide income, which might include:
We can advise on double tax treaties and help you avoid being taxed twice on the same income.
If you are moving to the UK and have foreign income or gains (such as interest, dividends, or income from overseas property or investments), it is important to understand how this will be taxed under the new Foreign Income and Gains (FIG) regime, which comes into effect on 6 April 2025.
The remittance basis will no longer be available from this date. Instead, a new system will apply that exempts foreign income and gains from UK tax for a limited four-year period, but only for individuals who have been non-UK tax resident for at least 10 consecutive years before becoming UK resident.
Key points:
If you have foreign income and gains arising after the four-year FIG period, or you do not qualify for the FIG regime, this income will need to be reported and taxed in full on your UK return.
For individuals who previously used the remittance basis, special transitional rules and planning opportunities — such as the Temporary Repatriation Facility and capital gains rebasing — may apply.
Read our full guide to the Foreign Income and Gains (FIG) regime
We will advise you on whether you qualify for the FIG regime, ensure the right amounts are included on your Self Assessment return, and help you manage the transition to worldwide taxation.
Here are some key points to remember:
We explain all of this and more in our introduction to Self Assessment.
Our firm provides a full Self Assessment service for overseas clients, including:
Contact us today for a no-obligation consultation.
Yes – you report different sources of income on separate sections of your Self Assessment tax return. We ensure each type is correctly reported and linked with the appropriate supplementary forms.
Possibly. If you are non-resident but receive UK income that hasn’t been fully taxed—or if you want to claim treaty relief or deductions—you will likely still need to file a return.
If you are UK tax resident, you are generally taxed on your worldwide income. We can help you correctly report both your UK and overseas income, and claim relief under double tax treaties where applicable.
The UK has tax treaties with many countries that help prevent double taxation. We’ll assess your situation and apply the appropriate relief or tax credit to your UK return.
The main return form (SA100) is standard, but the supplementary pages vary based on your circumstances—for example, there are separate sections for self-employment, rental income, foreign income, etc. We’ll prepare all the right parts of the return for you.
No. If your income is UK-sourced, you’ll need to report it in the UK even if you are already declaring it in another country. If double taxation relief applies, we can help you claim it in one country to avoid being taxed twice.
Need help understanding your UK tax obligations?
Let’s talk. We offer a free consultation to help you understand whether you need to register and what steps to take next.
Senior Manager
Head of Direct Taxes
Senior Associate
Global Mobility, Personal Tax & VAT
