Glossary
What is Opt-In Consent (SMS)?
SMS opt-in consent is the customer's explicit, recorded permission to receive text messages from a business — required by TCPA law and enforced by US carriers via 10DLC.
In depth
Sending business SMS without explicit prior consent violates the Telephone Consumer Protection Act (TCPA) and can result in $500-1,500 in statutory damages per unauthorized message. It also gets your sender number flagged by carriers and dropped into spam.
Proper opt-in consent has four requirements: (1) explicit affirmative action by the customer (checkbox, "reply YES," etc.), (2) clear disclosure of what they're consenting to, (3) recorded proof (timestamp, IP address, opt-in source), and (4) honored opt-outs (STOP keyword must work, and the unsubscribe is immediate).
Common ways to collect opt-in consent: checkbox during booking ("Yes, send me appointment reminders by SMS"), reply-YES double-opt-in to a confirmation message ("Reply YES to confirm reminders"), or customer-initiated conversation (customer texts your business first — that's implied consent).
Real examples
- 1.Booking form checkbox: "☑ I agree to receive SMS appointment reminders. Reply STOP to opt out anytime."
- 2.Double opt-in: customer is added to reminder list, gets a confirmation SMS asking "Reply YES to confirm reminders," only added if they reply YES.
- 3.Customer-initiated: customer texts your business asking to book — replying to them with reminders falls under implied consent.
BookIt records every opt-in consent (timestamp, IP, source) and handles STOP/HELP/START keywords automatically. Audit-ready out of the box.
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