A Payment Service Provider (PSP) is a financial institution that empowers merchants to accept a range of payment methods through a payment gateway. The PSP works in close relationship with acquiring banks (payment processors) to manage the transaction from the user's click to the merchant's payout. The PSP oversees every process from the moment the clients input their credit card data, to the moment the funds are transferes to the merchant’s bank account.
An end-to-end PSP should offer this minimum set of basic services:
Support for multiple currencies and payment methods,