SMS Opt-Outs: STOP, HELP, and the 10DLC Registration Trap
Since February 2025, the major US carriers block unregistered business texts outright. Not throttled, not delayed: blocked. The registration is a brand record, a campaign record, and a privacy policy that says one specific sentence, and missing any piece costs the fee anyway.
10DLC registration is mandatory for sending application-to-person SMS from a 10-digit long code in the United States. You register a brand, your legal business identity checked against IRS and state records, and one campaign per messaging use case, through The Campaign Registry. The brand record needs your exact legal name matching your EIN, a physical address matching your Secretary of State filing, and a live website with a privacy policy stating that SMS opt-in data is not shared with third parties. The campaign needs a description of the use case, the opt-in method, and two to five sample messages carrying your business name and STOP language.
Unregistered traffic does not get delivered
As of February 2025, every major US carrier, AT&T, T-Mobile, and Verizon, stopped delivering unregistered A2P business SMS. The messages do not arrive late or land in a spam folder. They are blocked. A store that has been texting customers from a long code without registering a brand and a campaign is not texting customers at all, and the first sign is usually a customer asking why the shipping updates stopped. The registration is not a best practice or a deliverability tip. It is the condition of delivery, and the carriers enforce it at the network level.
The Campaign Registry, known as TCR, is the system the carriers use to vet senders. Your messaging provider submits the registration on your behalf, but the record is yours: the brand is your legal identity, and the campaign is your use case. Registration is not optional for any business sending automated texts from a 10-digit number, and there is no grace period left to use. The stores still sending unregistered traffic are paying for messages nobody receives.
Related reading on this site: PrefEngine and Preference Center Placement: Footer Link, Checkout Checkbox, or Post-Purchase Ask cover the neighbouring problems in more depth.
The brand record is where most rejections start
The brand registration asks for the exact legal business name, matching the EIN records character for character, punctuation included. Sole proprietors without an EIN use a separate sole prop path, and get lower trust scores for it. The physical business address must match the Secretary of State filing, and the website must be live, on your own domain, with a visible privacy policy that covers SMS data and states you do not share opt-in data with third parties. Reviewers look for that specific sentence, and a privacy policy without it is a rejection.
The campaign registration is one campaign per use case, and the use cases are specific: customer care, two-factor authentication, account notifications, marketing, mixed, low-volume mixed, or a special category such as charity or political. A campaign needs a description naming the use case, the audience, and the consent method, plus two to five sample messages that include the business name and STOP language, and links only on the registered domain, with no public shorteners. Sending both promotional and transactional content means registering a mixed use case, because stretching a transactional campaign to cover marketing is an automatic rejection. Since March 23 2026, TCR returns granular error codes instead of generic rejection reasons, so each rejection points at the exact fix, but you still pay the campaign fee either way.
What it costs, and what STOP and HELP actually do
The fees are small and the stakes are not. Brand registration runs a few dollars, standard vetting runs around $40 and enhanced vetting around $100, campaign vetting runs roughly $15 per attempt, and a standard campaign runs around $10 a month. Processing typically takes one to seven business days, with most straightforward registrations approved within 24 to 48 hours. A registered brand with a high trust score can send 75 to 225 or more messages per second. An unregistered number is limited to about one message per second, when it is delivered at all.
STOP, HELP, and UNSUBSCRIBE must work on every number, on every message, automatically, with no human in the loop. Every marketing message should include reply STOP to opt out, reply HELP for help, and a note that message and data rates may apply, plus a link to terms and privacy policy at minimum on the first message and periodically after that. A single TCPA violation carries statutory damages of $500 to $1,500 per message, which is why the opt-out handling is not a courtesy. It is the part of the system that keeps a marketing program from becoming a legal problem.
Frequently asked questions
What is 10DLC registration?
It is the mandatory process for sending application-to-person SMS from a 10-digit long code in the United States. You register a brand, your legal business identity, and one campaign per messaging use case, through The Campaign Registry, and carriers block unregistered traffic outright.
What does a 10DLC brand registration need?
Your exact legal business name matching your EIN records, a physical address matching your Secretary of State filing, and a live website with a privacy policy stating that SMS opt-in data is not shared with third parties for marketing.
How many sample messages does a campaign need?
Two to five, each carrying your business name and matching the declared use case, with at least one carrying opt-out instructions, and links only on your registered domain. A campaign for each use case is required, and a mixed use case covers both promotional and transactional content.
Do STOP and HELP have to work automatically?
Yes. Your platform must process STOP, HELP, and UNSUBSCRIBE without human intervention, on every number and every message. A single TCPA violation carries statutory damages of $500 to $1,500 per message.