What are your FX rates?
This article explains what you will and won't charged currency exchange rates for
If your NUMARQE card is set up for GBP, EUR, or USD you will not be charged an FX fee to transact between them.
Any transaction or refund to and or from currencies to a card that is not set up for that currency (E.g. GBP / EUR / USD) will incur FX fees.
A charge or refund will be converted into the card currency using the NUMARQE Exchange Rate.The conversion will take place on the date the charge or refund is processed by us, which may not be the same date that you or the cardmember authorised the charge or the date of the refund. The Numarqe Exchange Rate is set daily between Monday and Friday, except Christmas Day and New Year’s Day.