First time Sole Trader in UK. Can I work completely in euros?

[cprcrack]

Hi all, I'm new to UK business and your help would be hugely appreciated.

I just moved to the UK and will work as a sole trader here. My business is totally online, basically my income comes from AdSense/Admob (Google Ireland Ltd.). I want to keep my current Spanish AdSense account, which means Google will only pay me to a Spanish bank account in euros.

I actually like that, but wonder if this is allowed by the HMRC. I will work completely in euros, using my Spanish bank account, and I will not even have any business bank account in pounds. I will not be VAT registered so all my invoices will also be in euros. My concrete questions are:

1- Is this actually allowed by the HMRC? Can I simply keep all records in euros in a simple Excel file like I have been doing in Spain?
2- Do I actually need to make an invoice for Google Ireland Ltd or will a proof of the income like the bank transfer receipt be enough? Payment receipt issued by Google show my Spanish address, which I guess is not desirable.
3- When paying Income Tax through Self Assessment, can I simply convert my profit from EUR to GBP at the time of filling the Self Assessment so that the HMRC knows how much to charge me?

Thanks a lot!

[RMC]

For HMRC-approved currency conversions see
https://www.gov.uk/government/collectio ... ms-and-vat
In the UK one can also trade using cryptocurrencies.