A2P 10DLC registration (US SMS)

US carriers require application-to-person (A2P) registration on the 10-digit long code (10DLC) protocol. Unregistered SMS is blocked or massively throttled.

Two registration steps

1. 1
   Register the brand

   Business legal name, EIN, address, website. 1-3 days to approve.
2. 2
   Register a campaign

   Use case (marketing, mixed, customer care, etc.), sample messages, opt-in method. 1-2 days to approve.
3. 3
   Attach campaign to numbers

   Your existing numbers migrate to the campaign. New numbers auto-attach.

Get approved first time

• Provide a live URL that shows your SMS opt-in method.
• Include "Msg & data rates may apply. Reply STOP to opt out." in your sample messages.
• Match the use case to your actual sending patterns — do not register Marketing and then send service reminders only.