A2P 10DLC
The US carrier registration system that lets businesses text from standard 10-digit numbers without being filtered.
A2P 10DLC (Application-to-Person 10-Digit Long Code) is the registration framework US carriers require for business texting from normal phone numbers. You register your brand (legal identity) and your campaign (use case + sample messages), and carriers assign throughput.
Unregistered traffic gets filtered, so registration is a prerequisite for reliable business SMS — not an optional step. Vague use-case descriptions and mismatched sample messages are the common causes of rejection.
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