Originally Posted by Boraxo
One thing that I found puzzling was that both Citi and CapOne used different exchange rates for multiple transactions that occurred on the same day.
Does the conversion rate used by Visa float throughout the day (in sync with the markets)?
My experience with Mastercard charges (can't remember if I've used Visa overseas) is that they use the exchange rate in effect the day before the transaction posts. In effect they fix the exchange rate at the end of the day and use that for all transactions that post on the following day. So if you buy something on 3/1, it most likely posts on 3/2 so they use the 3/1 exchange rate. But then if you buy another item on 3/1 and the merchant delays in uploading the transaction and it doesn't post until 3/3, then they'll use the 3/2 exchange rate.