How to Convert Foreign Currency into GBP for Your UK Tax Return
If you receive income or gains in a foreign currency, you must convert these amounts into British pounds sterling (GBP) before declaring them on your UK Self Assessment tax return. This is necessary because HM Revenue & Customs (HMRC) requires all taxable income and gains to be reported in GBP.
Steps to Convert Foreign Currency
Identify the Foreign Income Amounts
Gather all your foreign income or gains figures, including wages, dividends, rental income, pensions, or capital gains paid in foreign currency.
Choose the Appropriate Exchange Rate
HMRC allows some flexibility in the exchange rate you use, but you must apply a "just and reasonable" rate.
We would suggest using official published HMRC exchange rates where available:Calculate the GBP Equivalent
Multiply the foreign currency income by the selected exchange rate to get the GBP figure. For example, if you received €1,000 and the exchange rate is 0.85 GBP per Euro, the GBP amount is £850.
Record and Report in Your Tax Return
Enter the converted GBP amount in the foreign income section of your Self Assessment tax return.
Keep records of your calculations and the exchange rates used in case HMRC requests evidence.
Additional Points to Remember
If you have already paid foreign tax on the income, you may be eligible for Foreign Tax Credit Relief to avoid double taxation.
Different categories of foreign income (such as pensions, dividends, or rental income) may have specific reporting rules.
If you receive multiple payments at different times, it’s often easiest to convert the total on an average for the year but it can sometimes work out better by converting each payment using the exchange rate applicable on its receipt date.
Retain documentation for at least 5 years after the relevant tax year.
Summary
To convert foreign currency to GBP for your tax return: gather foreign income details, use a reasonable exchange rate (preferably HMRC's official rates), convert to GBP, and report the amounts accurately in your Self Assessment return.