Missed-call text-back looks like the easiest automation to switch on. Someone calls, nobody picks up, and a text goes out seconds later. Then you notice it went to a person who never typed a word to you.
The rules around that text matter more than the speed. This article covers what the primary sources say and the decisions they leave to you. It is not legal advice, so run your setup past your own counsel.
A missed call is not a text opt-in by itself
CTIA is the wireless industry trade group. Its [Messaging Principles and Best Practices](https://api.ctia.org/wp-content/uploads/2023/05/230523-CTIA-Messaging-Principles-and-Best-Practices-FINAL.pdf) sort business texts into three kinds. In a conversational exchange the consumer texts first and the business only responds with relevant information, and CTIA expects no additional permission. Informational texts follow a consumer who gave their number and asked to be contacted. Promotional texts push a sale, and CTIA says the consumer should agree to those in writing.
A missed-call reply fits none of them cleanly. The caller dialed you. They did not text, and may not have asked for one. Whether that is enough consent is a legal question, and nobody should guess, including a vendor.
You can ask before the call goes unanswered. CTIA lists opting in by phone, through interactive voice response, as one way to show consent. A menu that says "press 1 and we'll text you" is closer to that than a greeting that only announces it. Whether either is enough is a question for counsel.
Keep records either way. CTIA suggests retaining the timestamp, the medium, the wording, and the number. Store the call time and the greeting version live then.
Register before you send
Business texts from a normal 10-digit local number are A2P 10DLC. [The Campaign Registry](https://www.campaignregistry.com/) is the registry the carriers use. It describes 10DLC as a channel where brands and campaign service providers are verified before they send. It also says a business cannot register directly. Your texting provider registers you as a brand, then each campaign.
Ask your provider whether each sending number must be attached to an approved campaign, and what happens if it is not. Carriers set their own enforcement, so test on phones from different carriers. "Sent" in a dashboard means the provider accepted it, not that the caller got it.
Describe the campaign as it runs. If you register replies to inbound callers, do not send a seasonal promotion from the same number. Register what you send, and send what you registered.
Treat STOP as a system rule
The FCC's [TCPA consent order](https://docs.fcc.gov/public/attachments/FCC-24-24A1.pdf) says any reasonable method revokes consent. Replying "stop," "quit," "end," "revoke," "opt out," "cancel," or "unsubscribe" counts as reasonable without argument. [47 CFR 64.1200(a)(10)](https://www.law.cornell.edu/cfr/text/47/64.1200) requires honoring a request within a reasonable time, no more than ten business days, and allows one confirmation text with no marketing.
CTIA asks for more. Opt-out instructions should use standard "STOP" wording, and plain requests like "please opt me out" should also be acted on, whatever the capitalization. Senders should support more than one way out, including phone and email. After one confirmation message, nothing else goes out. Ten business days is a ceiling, so process STOP on arrival.
One piece is pending. The rule would treat a revocation sent in reply to one kind of message as covering all later robotexts from that sender, even on unrelated topics. The FCC [extended the date for that part to January 31, 2027](https://docs.fcc.gov/public/attachments/DA-26-12A1.pdf) while it reviews comments, and it may change the rule. Do not build around the delay. Keep one suppression list per number that every tool reads.
Test before launch:
- "STOP," "stop.", "Unsubscribe," and "please opt me out" all suppress the number. - A caller who texted STOP and then calls again gets no automatic text-back. - The opt-out reaches every tool that texts, not only the sender.
Keep service texts and marketing texts apart
CTIA notes that adding a call to action, such as a coupon code, to an informational text may move it into the promotional category. So the missed-call reply carries no discount, financing offer, or promo link.
Hypothetically, a roofer's text-back reads "Sorry we missed you. Ask about our fall discount." The caller only phoned. That is a promotional text to someone who gave no marketing consent. CTIA says an opt-in applies only to the campaign it was obtained for, and someone who calls about a leak has not joined your newsletter. To market to them later, collect separate written consent.
What the first text should say
Short and about the call. A hypothetical roofer's version:
> Hi, this is Example Roofing. Sorry we missed your call. What can we help with? Reply here and a person will answer during business hours. Reply STOP to opt out.
And a hypothetical freight brokerage's:
> This is Example Freight. We missed your call. Is this about a new quote or a load already moving? Reply with which one and we'll route it. Reply STOP to opt out.
Rules for yours:
- Name the business first. - Say you are texting about the missed call. - Ask one question. - Say who will answer and when. If software handles replies, say so. - Include how to stop. - Leave out prices and offers. - Skip links. CTIA says a URL shortener, if used, should be dedicated to your business alone, which rules out public ones. - Send one text per missed call, and set a wait before the same number can trigger another.
Landlines cannot receive texts. Have the system skip them and flag the call for a person.
If you want help planning missed-call text-back for your roofing or freight business, [book a call with Chosen AI Solutions](https://chosenai.co/book).
Sources
- CTIA. [Messaging Principles and Best Practices](https://api.ctia.org/wp-content/uploads/2023/05/230523-CTIA-Messaging-Principles-and-Best-Practices-FINAL.pdf), May 2023. - The Campaign Registry. [10DLC overview](https://www.campaignregistry.com/). - FCC. [Report and Order, FCC 24-24](https://docs.fcc.gov/public/attachments/FCC-24-24A1.pdf), February 2024. - FCC. [Order, DA 26-12](https://docs.fcc.gov/public/attachments/DA-26-12A1.pdf), January 2026. - [47 CFR 64.1200](https://www.law.cornell.edu/cfr/text/47/64.1200), Cornell LII.