US Patent 11861581 Payment by use of identifier

Described is a technology that enables a customer, who uses a payment card in a point-of-sale (POS) transaction and provides a biometric identifier to the merchant, to use the biometric identifier as a payment mechanism in future transactions. In some embodiments, the technology involves communication between a customer's user device, a payment service system (PSS), and one or more merchant POS systems. A merchant POS system collects information around the time or after the time of the POS transaction between the merchant POS system and the customer, including, among others, a biometric identifier of the customer and forwards this information to the PSS. The PSS stores the biometric identifier in association with the payment card used in the transaction. In a second transaction, the customer may provide the biometric and the PSS may process the transaction based at least in part on the identifier without the customer needing to provide a payment card.