Will I be taxed twice on foreign income as a UK resident, and how do I get relief?

Checked on 2026-10-25

Usually you get relief. If you already paid foreign tax on income that is also taxable in the UK, you can normally claim Foreign Tax Credit Relief in your Self Assessment return, which reduces your UK tax by the foreign tax. You may get back less if the tax treaty sets a lower amount or the UK rate is lower.

Key facts

What	The law or guidance says	Source
Who pays UK tax on foreign income	UK residents normally pay UK tax on all their income, from the UK or abroad; non-residents only on UK income	GOV.UK, UK residence and tax
Already taxed abroad	You can usually claim Foreign Tax Credit Relief when you report the income in your tax return	GOV.UK, If you’re taxed twice
Effect of the credit	The UK Income Tax or Capital Gains Tax on that income or gain is reduced by the amount of the credit	TIOPA 2010 s. 18(2)
No tax treaty	Relief is usually still available, unless the foreign tax does not correspond to UK Income Tax or Capital Gains Tax	GOV.UK, If you’re taxed twice; TIOPA 2010 s. 9
How much	May be less than the foreign tax paid: if the treaty sets a smaller amount, or the income would have been taxed at a lower rate in the UK	GOV.UK, If you’re taxed twice
Not yet taxed abroad	Apply for relief in the country the income comes from, with a form confirmed by HMRC or a UK certificate of residence	GOV.UK, If you’re taxed twice

If the foreign tax is already paid

GOV.UK says you report the overseas income in your Self Assessment tax return and claim Foreign Tax Credit Relief there. How much relief you get depends on the UK’s double-taxation agreement with the country the income comes from. The law (section 18 of the Taxation (International and Other Provisions) Act 2010) says that where credit is allowed, the UK tax on that income or gain is reduced by the credit.

Without an agreement, section 9 of the same Act gives unilateral credit for tax paid under the other country’s law on income arising there, if that tax corresponds to UK tax. GOV.UK puts it as: you usually still get relief, unless the foreign tax does not correspond to UK Income Tax or Capital Gains Tax.

You may not get back the full amount. GOV.UK says you get less if the agreement sets a smaller amount, or if the income would have been taxed at a lower rate in the UK. You can’t claim this relief at all if the agreement requires you to claim the tax back from the other country.

If the foreign tax isn’t paid yet

GOV.UK says you have to apply for relief in the source country if the income is exempt from tax there but taxed in the UK (its example: most pensions), or if that country’s agreement requires it. You prove you are eligible either by sending that country’s form to HMRC, which confirms your residence and returns it, or by including a UK certificate of residence if you apply by letter.

Capital gains

GOV.UK says that for capital gains you usually pay tax in the country where you are resident and are exempt in the country where you made the gain, without needing a claim. Different rules apply to assets that can’t be taken out of the country, such as land or a house, and to assets used for business there: then you pay tax in both countries and get relief from the UK.

Dual residence: you can be resident in both the UK and another country; HMRC has separate guidance on claiming relief as a dual resident (GOV.UK, If you’re taxed twice).
New residents who qualify for the 4-year foreign income and gains regime can instead claim relief from UK tax on eligible foreign income (HMRC, 4-year FIG regime guidance).

Sources

GOV.UK: Tax on foreign income, If you're taxed twice checked 2026-10-25
GOV.UK: Tax on foreign income, UK residence and tax checked 2026-10-25
Taxation (International and Other Provisions) Act 2010, section 18: credit for foreign tax reduces UK tax (legislation.gov.uk) checked 2026-10-25
Taxation (International and Other Provisions) Act 2010, section 9: unilateral credit for non-UK tax (legislation.gov.uk) checked 2026-10-25

Change history

2026-10-25: Page created

This is general information, not legal advice, and Lumen is not a law firm. Rules change and offices differ: check the official sources above before you act. Found something wrong or out of date? Write to support@lumen.observer.