10DLC and A2P for voice agents

What is 10DLC / A2P?

10DLC (10-Digit Long Code) is how US carriers let businesses send application-to-person (A2P) SMS from a normal 10-digit phone number. To send that traffic, you register your business and your use case through The Campaign Registry (TCR). Unregistered A2P messages get filtered, throttled, or blocked.

Does my voice agent need it?

If your agent sends any SMS (appointment confirmations, callback texts, lead follow-ups), yes. Voice-only calling has its own rules (STIR/SHAKEN caller ID attestation), but most voice products also text, so most builders hit 10DLC. If you never send SMS, you can defer it, but plan for it before you scale.

The two registrations

• Brand: your business identity (legal name, EIN, address). Carriers vet it and assign a trust score that sets your throughput.
• Campaign: the specific use case (for example "appointment reminders"), with sample messages and opt-in details.

Timeline

The wait is the carrier / TCR review queue, not your code. No boilerplate can remove it, so start the registration early and build in parallel.

Costs and gotchas

• A one-time brand vetting fee, monthly campaign fees, and per-message carrier fees. Amounts vary by provider and trust score.
• Sole proprietor brands have much lower throughput than standard (EIN-backed) brands.
• Opt-in language and sample messages must match what you actually send, or the campaign is rejected.
• Unregistered traffic is increasingly hard-blocked, not just filtered.