TextBelt is a telephony service. It provides outgoing SMS services for developers. TextBelt uses carrier-specific gateways to forward free SMSâ€™s without advertisements. It can be used for testing SMS functions instead of Twilio. It supports a large variety of U.S. providers, including Alltel, Verizon, Virgin Mobile, and many more. The entire TextBelt service is a RESTful API that sends messages and responds with success or failure notices.