10DLC Frequently Asked Questions

Answers to the most common 10DLC and SMS compliance questions — registration, consent, spam filtering, carrier rules, STOP/HELP and message examples.

By 10dlccheck Editorial · Published · Updated · ~4 min read

Overview

10DLC (ten-digit long code) is the US carrier-approved channel for application-to-person (A2P) texting using standard local numbers. To send A2P traffic on 10DLC, brands register with The Campaign Registry (TCR), then register a campaign and assign phone numbers before sending.

Carriers enforce policies on consent, brand identification, STOP/HELP support and restricted content. Non-compliance can result in filtering, blocking or account suspension.

New to 10DLC? See What Is 10DLC? on the hub page for a quick primer on how registration works.

Registration

Do all major US carriers require 10DLC registration?

Yes. AT&T, T-Mobile and Verizon all require brands and campaigns to be registered via TCR and enforce content and consent rules across A2P long-code messaging.

What are the core registration steps?

  1. Register your brand — legal entity name, EIN/Tax ID, address and website.
  2. Register a campaign — select your use case, document your opt-in method and provide three sample messages.
  3. Assign numbers — link long codes to your approved campaign before sending any traffic.
Example (AT&T): Admin Portal → Enhanced Business SMS → 10DLC Registration → create brand → create campaign → assign numbers.

Where do I complete registration?

Most businesses register inside their messaging platform's admin portal, which submits details to TCR on your behalf. Look for "Messaging", "Compliance" or "Trust Centre" sections. Keep screenshots and logs of your opt-in flow — timestamps, IP, form text and source — for audits and carrier reviews.

What consent elements do carriers expect?

  • Documented opt-in obtained before sending any messages
  • Sender identity disclosed at the start where practical
  • STOP and HELP keyword support
  • Clear programme terms: message frequency and "message and data rates may apply"
  • Risk-aware links — avoid public shorteners on first contact

Do I need STOP/HELP in every message?

Single-message programmes may not display STOP/HELP in that one message, but systems must still support those keywords. Ongoing programmes should include STOP instructions in the first message and respond to HELP with support contact information.

Content and restrictions

What content is restricted or prohibited?

  • Illegal content is never allowed
  • No SHAFT content (Sex, Hate, Alcohol, Firearms, Tobacco)
  • No scams, get-rich-quick schemes or high-pressure financial claims
  • High-risk finance and aggressive claims face strict scrutiny

Can I use public link shorteners like bit.ly?

Avoid public shorteners in first contact. Use branded or first-party links tied to your business to reduce carrier filtering risk. See the identity guidance in our CTIA checklist for more detail.

What sample messages should I provide to TCR?

Provide three unique, accurate examples that match your declared use case, clearly show brand identity and include opt-out language. Do not copy generic templates — carriers compare samples against actual sent traffic.

Channel comparison

How does 10DLC compare to short code and toll-free SMS?

Channel Best for Pros Considerations
10DLC Local presence & two-way Recognizable number; cost-effective Brand & campaign registration required; content rules apply
Short code High-volume national alerts Very high throughput More expensive; longer approval timelines
Toll-free SMS Support & notifications Nationwide reach Verification recommended; content rules still apply

Filtering and delivery

Will unregistered or non-compliant traffic be filtered?

Yes. Carriers use content and behaviour-based filtering including machine-learning systems. Unregistered traffic and deceptive content are more likely to be blocked or rate-limited. Keep messaging aligned with your registered campaign type and use consistent sending patterns.

What do carriers say about A2P channels?

Verizon lists short code, toll-free and 10DLC as recognised A2P channels. T-Mobile requires adherence to its Code of Conduct and CTIA Principles. AT&T publishes step-by-step TCR registration instructions for business products.

Message examples

Compliant first message

"BrandName: Thanks for joining delivery alerts. Up to 4 msgs/mo. Msg&data rates may apply. Reply STOP to opt out, HELP for help."

  • Brand identified
  • Frequency disclosed
  • STOP and HELP included
Risky first message

"You are pre-approved — claim now: bit.ly/xxxx"

  • No brand identity
  • Public link shortener
  • No opt-out instructions
  • Implied financial claim

Official references