10DLC registration guide for cold SMS (US carriers in 2026)

Short answer: to send cold/business SMS to US numbers in 2026 you must register a 10DLC brand (your company) and at least one campaign (your use case) with The Campaign Registry via your carrier. Unregistered A2P traffic is now filtered by 90%+ at the carrier.

The registration path

1. Register your brand — legal entity, EIN, address. Takes minutes; vetting is near-instant for most.
2. Register a campaign — describe the message flow, opt-in method, and sample messages.
3. Get your SID — the campaign SID is attached to your sending number.

What gets you filtered

• No opt-in language / no clear sender identity.
• "SHOP" / loan / high-risk content on a low-trust campaign tier.
• Sending before registration completes.

Autocloz won't let you send unregistered

Autocloz refuses to dispatch SMS through an account whose 10DLC brand + campaign SIDs aren't present, and auto-honours STOP as a cross-channel DNC. That keeps your numbers off the carrier blocklist.

> Start free — connect a Twilio/Telnyx/Bandwidth number and Autocloz checks 10DLC before the first send.