Foreign currency exchange rate

Dear Sir/Madam, May I know if HRMC has guideline on using the (1) monthly rate, (2) average rate and (3) spot rate when calculating the foreign currency conversion in tax return? Thanks and regards, Maggie

Hi Maggie Wong,
Under the terms of Self Assessment, we do not provide an official exchange rate and the onus is on the individual to use a just and reasonable exchange rate for each acquisition and disposal.
You are free to use any of the three rate HMRC provides, or you can use a rate obtained elsewhere, such as a newpaper or the London Stock Exchange.
Link to HMRC rates here: 
Exchange rates from HMRC in CSV and XML format
Thank you.