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STOP, START and HELP: how text opt-outs work

A client who texts STOP is opted out of every text from your brand until they text START.

Updated September 24, 2026

The Texts screen in Purity, with example data
The Texts screen, with example data.

These are carrier-required keywords. Purity watches for them on every inbound text to your number, not just replies in an open conversation.

  • STOP (also STOPALL, UNSUBSCRIBE, CANCEL, END, QUIT, OPTOUT, REVOKE) opts that phone number out of every text from your brand, including order updates and automations. Purity sends one confirmation reply and adds the number to your do-not-message list.
  • START (also UNSTOP, SUBSCRIBE, YES) opts the number back in and sends a confirmation reply.
  • HELP sends your support email back to them, if you have one set in Settings.

The keyword and the confirmation reply both show up as messages in that conversation, so you can see it happened.

Once a number texts STOP, nothing can be sent to it from Purity, including replies typed in the conversation. The conversation shows "Texted STOP" and the message box is replaced with a note until they text START.

You can see every opted-out number, and why, on the do-not-message list in Signup and consent.