Mastercard and Visa are both payment systems used for credit, debit and pre-paid currency cards.
When making a purchase with your card, the payment system provides communication between the point of purchase and your bank, managing the way in which the transaction is accepted, authorised and processed.
You'll still pay your bank or building society and when you pay your credit card bill it's your bank you'll pay.
Account providers will also set any interest rates and reward points associated with your account as well as issuing the card to you.
Does my card use Mastercard or Visa?
Most cards will carry the payment scheme's logo on the front.
In addition, you can look at the first digit of the long number on the front of your card. Cards using Mastercard start with a 5. Cards using Visa start with a 4. See our credit cards 101 infographic for a complete guide to the meaning behind the other numbers on your card.
All new cards issued by Sainsbury's Bank use the Mastercard payment system.
What's the difference between Mastercard and Visa?
Both systems are used Worldwide and it's now rare to find a location where one is accepted and the other isn't.
Some people like to carry two cards, one using each payment system, just in case.
Both Mastercard and Visa provide customers with an extra layer of security when using their cards online.
Mastercard SecureCode and Verified by Visa let customers set up a secret message, code or password for each card. This adds an extra security step by providing another layer of authentication.
Both services are free and customers can sign up on the provider's website. You'll find more information in our guide to credit card security.
Which card should I choose?
Remember, it's the card issuer (banks and buildings societies) who set interest rates, any interest free periods, fees and reward points which apply to your card. Think about how you want to use it and choose the one which gives you the best deal.
View all Sainsbury's credit cards.