What Senders (Originators, Numbers) are supported in the US for A2P SMS/MMS Services?
All A2P Senders in the US are Dedicated 2-way Products. They all require some level of registration for the Brand (Sender) to the number(s). They all must support/respond accordingly to mandatory Keywords for STOP (Opt-out) and HELP (Customer Support). Supported Originators are Short Code, 10DLC (Local Numbers) and Toll Free Numbers (TFN). Alpha is not supported today.