We always check the currency in which your transaction is first. If its balance is not enough, we will then check your account's base currency. If that also can't cover the transaction and you have cash in other currencies, we will use the next currency with the most free funds.
📝Note: One transaction will always be completed in one currency. We will not combine funds from different currencies to complete a purchase.
💡Example: You have an account holding multiple currencies, with a distribution of 80 GBP, 150 USD and 120 EUR.
You try to buy something for 100 GBP. The funds in the main currency (GBP) are not enough, so the system will automatically use your second-highest balance (USD) to cover the whole cost.