63106: phone_number is not a RCS capable number

Twilio returns this error when the phone_number you supplied is not RCS capable. RCS Business Messaging uses a branded sender profile rather than a traditional phone number, and RCS is compatible with Android devices and iOS devices running iOS 18 or later.

• The recipient device or carrier does not support RCS, so Twilio cannot use that number for an RCS delivery. Twilio attempts RCS first only when the destination is RCS-capable, and it falls back to SMS when RCS is unavailable.
• You are trying to use a Twilio number as an RCS test device. Twilio numbers cannot be used as RCS test devices.
• The RCS sender has not been approved for messaging to that number yet. Before you message phone numbers that are not added as test devices, carrier approval is required.

• Send to a number tied to an RCS-capable device. Twilio supports RCS on Android devices and iOS devices running iOS 18 or later.
• Add the destination as a test device during RCS onboarding, or test with an Android device that you allowlist for onboarding.
• Configure RCS plus SMS fallback with a Sender Pool when you want Twilio to deliver via RCS first and switch to SMS when RCS is unavailable.

• RCS Business Messaging
• Get started with branded RCS messaging
• Channel Fallback