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CommCare has a set number of existing custom gateways in its system that are only available in certain countries. To see a full list of available gateways, go to Messaging -> SMS Connectivity in your CommCareHQ project space. From there you can choose one to use for your project.
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There are a few global gateways (US phone numbers) but these are more expensive for sending and receiving international messages. Twilio gateways use phone numbers maintained by CommCareHQ to send messages inside the US and a limited number of international countries. The per message rates can be high based on the country destination.
Please note that Dimagi does not create new custom gateways upon request, and we cannot guarantee the reliability of gateways as they operate independently of CommCare.
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