When you use the card in a store, no money is transferred directly from you to the store immediately. What happens is that the store contacts the card issuer through a transaction keeper and asks for authorization of the purchase on this card. If the card issuer approves the transaction, which occurs when there is sufficient balance in the account, etc., then we will create a reserve on your account. This reservation usually only lasts for 1-3 days, but we automatically cancel it after 7 days.
After the payment has been authorized, the store sends sales notes to VISA through its transaction keeper, and then VISA sends us the settlement transactions. Only then do these pending transactions turn into final transfers. This process is usually completed 1-3 days after you activate the card.
There are several reasons for having pending transactions. One example is when you go to a gas station and choose "Fill up." In this case, there will be a reservation for, let's say, 30 thousand, but if you only pump for 11 thousand, the transaction will be updated from 30 thousand to 11 thousand, and you will have immediate access to the remaining 19 thousand ISK difference.
Pending transactions can also be canceled, for instance, if the purchase is not completed for any reason, or if the authorization is used as a guarantee for a hotel room or car rental, etc.