Glossary
What is STOP keyword?
A STOP keyword is a reply word, usually STOP, that a texting platform treats as a request to opt out and acts on without anyone needing to read it.
'Reply STOP to opt out' became the UK habit because it's short, people recognise it and it fits on the end of a text. The ICO's PECR guidance uses the same idea in its example of good practice, 'To opt out text STOP to 12345'. Other words get used too, and a good system listens for them.
A customer of a Liverpool takeaway who replies 'Stop' to a Friday offer shouldn't hear from that takeaway's marketing again unless they ask to.
CaptiFi Connect treats STOP, STOPALL, STOP ALL, UNSUBSCRIBE, CANCEL, END, QUIT, OPTOUT and OPT OUT as opt-outs, and START or UNSTOP as opting back in, in any mix of capitals and ignoring punctuation. The reply has to be the keyword on its own, so 'please stop texting me' goes to your inbox and you add the number to the opt-out list yourself. A keyword reply triggers the opt_out.created webhook; numbers you add by hand, by import or through the API don't. No automatic reply goes back to the person.