Not only is it a best practice to offer an opt-out option to your members, but it is law in some countries. Twilio offers default opt-out keywords like STOP, UNSUBSCRIBE, STOPALL, CANCEL, END, and QUIT, but you can customize this list of opt-out keywords. You can also offer an option to opt back in to your messages with custom keywords.

Opt-out applies to two-way messaging because your members can reply back to your number. For one-way messaging where they can't reply to your message, offer another way for your members to opt out, such as contacting your church or texting a different phone number.