A customer of a multi-channel message exchange system provides criteria for selecting a service provider using an application programming interface (API). The multi-channel message exchange system selects a service provider that is best suited to deliver each individual message, via a network, for the customer. The message exchange system selects a service provider based on customer criteria, service provider data structures, and other information. The criteria may include a maximum value, a minimum quality score, a maximum latency, or any suitable combination thereof. The data structures may include geographic jurisdictions in which the service provider provides network-based message delivery, channels through which the service provider is willing to deliver messages, or any suitable combination thereof.