To stop receiving new SMS messages, recipients can use the STOP, STOPALL, UNSUBSCRIBE, CANCEL, END, or QUIT keywords.
When recipients opt-out, they will receive the default reply:
You have successfully been unsubscribed. You will not receive any more messages from this number. Reply START to resubscribe.
Any future attempts to send an SMS to the recipient will fail with a Failed - not delivered message.
Only single-word messages will trigger the block or unblock. So, for example, replying STOP will stop the recipient from receiving messages, but STOP PLEASE or PLEASE CANCEL will not.
Please note that these keywords only apply to the most recent number that messaged the recipient.
Recipients can resume receiving messages with the START, YES, or UNSTOP keywords.
When recipients opt in, they will receive the default reply:
You have successfully been re-subscribed to messages from this number. Reply HELP for help. Reply STOP to unsubscribe. Msg&Data Rates May Apply.
