Abstract: Example card processing methods and systems are described. The card processing system may receive a request to approve or reject a transaction using a multicurrency card with multiple account balances in multiple currencies. The transaction may be associated with a transaction amount in a transaction currency. In response to determination that the first account balance is not available or insufficient to fund the transaction amount, the card processing system may determine, from the multiple account balances, a second account balance in a second currency that is different to the transaction account to fund the transaction amount. An exchange rate may be selected for dynamic currency conversion of part or all of the second account balance from the second currency to the transaction currency; and a determination made as to whether to approve or reject the transaction based on the dynamic currency conversion using the selected exchange rate.