To send money, users will tap the "$" icon and enter the amount. The first time users send or receive money, they will add a Visa or MasterCard debit card.
After creating a PIN (or using Touch ID on iOS devices), users will be able to send money to friends.
"Incorporating security best practices into our payments business has always been a top priority, Facebook said on Tuesday. "We use secure systems that encrypt the connection between you and Facebook as well as your card information when you ask us to store it for you."
The feature should roll out over the next few months and will be available on Android, iOS and desktop.