MB WAY is a mobile payment service in Portugal that allows users to make payments, transfer money, and perform other financial transactions using their smartphones. It's operated by SIBS, a company that provides payment services in Portugal. With MB WAY, users can link their bank accounts and debit/credit cards to their mobile phones, enabling them to make purchases in stores, online, or transfer money to other individuals who also use the service. It's widely used for its convenience and security features.