When a credit or debit card is swiped, a percentage of the transaction is paid to the card's issuing company as transaction fees. The fee is typically 2-3% of the amount paid by the consumer and is typically absorbed by the merchant or store where the purchase is made. In the case of gasoline transactions, the fee should ideally be borne by the petrol pump dealers. However, because fuel businesses have low-profit margins, the transaction fee is passed on to consumers. As a result, the fee added on top of the actual fuel charge is known as the fuel surcharge. When you use a credit card to buy gas, you will be charged a fuel surcharge as well as the service tax levied on the surcharge.