My understanding, if your bank charges 2.5%, then it will use the mastercard/visa conversion rate (which is market rate plus a very small amount like 0.4% based on mastercard currency converter), plus 2.5% from your bank.
so my question is, is this always the case, or can one bank use some other conversion rate other than the mastercard/visa one, THEN charge the extra 2.5%?
From CIBC: https://www.cibc.com/ca/pdf/credit-cards/d8419-cibc-dividend-sumbox.pdf
Foreign currency transactions, except Convenience Cheques, are converted to Canadian dollars on or after
the transaction date and before the posting date. You are charged the same conversion rate CIBC must pay,
plus a fee of 2.5% of the converted amount
so this "same conversion rate CIBC must pay" , is that the same mastercard/visa rate, or is it something else?