We built this tool to remove guesswork. If you have ever wondered why a text might get blocked or flagged, this page explains our approach and how to get the most from the checker. For support, email support@10dlccheck.com.

Our mission

Make SMS compliance clear and practical for everyone. We focus on plain language, useful guidance, and fast checks that help you send with confidence.

What the tool does

  • Checks for brand identification, STOP and HELP language and opt out handling.
  • Flags risky words and patterns that carriers commonly filter.
  • Explains why something is a risk and offers safer wording you can copy.
  • Links to short guides in the Learn hub when you want more detail.

How we align with CTIA guidance

Our checks reflect widely adopted practices from the CTIA’s Messaging Principles & Best Practices and supporting materials. In plain terms, that means:

  • Consent comes first. Only message people who opted in. Keep records of when and how they opted in.
  • Identify your brand. State who you are in the message, especially in the first one.
  • Honor keywords. Process STOP requests immediately and return helpful info on HELP.
  • Mind high-risk content. Avoid prohibited or sensitive categories without proper safeguards and age gating where required.
  • Use trustworthy links. Prefer branded or first-party domains. Avoid suspicious redirects and public link shorteners in cold outreach.
  • Respect frequency and quiet hours. Send what you promised at opt-in and avoid disruptive timing.

For deeper reading, see CTIA’s Messaging Principles & Best Practices (PDF) and the Short Code Monitoring Handbook (PDF).

Major U.S. wireless providers

Most 10DLC compliance requirements in the U.S. are enforced across these large networks:

  • AT&T
  • T-Mobile
  • Verizon
  • UScellular (regional)
  • Boost Mobile (DISH / EchoStar group, operates through partner networks)

Many MVNOs (resellers) operate on the big networks listed above, so carrier rules still apply even if you use a smaller brand.

Who we serve

Marketers, sales teams, founders, compliance reviewers, and developers who need a quick pre-send check for U.S. A2P 10DLC messaging. If your brand texts customers, this gives you a faster path to clarity and better deliverability.

Learn and extensions

New to 10DLC? Start with What is 10DLC. Then try a few sample messages in the checker. You can also add the Chrome extension for quick checks while you work.

Try the checker

Run your message and get instant guidance before you hit send.

Check now →   Chrome extension

Contact

Questions or feedback? Email support@10dlccheck.com. Found a pattern we should flag? Open an issue on our repository: github.com/I4petranelle/10dlccheck.