The STOP function cannot be changed but in certain circumstances the content of the message that is sent in response to a STOP request can be changed.
- The STOP function is a carrier-regulated command word that cannot be modified. Note that "QUIT" and "CANCEL" also function the same way for short codes.
- The STOP function cannot be controlled or modified by keyword.
- When multiple keywords are active for a number the mobile user will always receive the option to select which keyword they want to opt out of if they send "STOP." A typical response to a "STOP" message when the mobile number is opted into multiple keywords would be, "Multiple keywords active. Reply with one of NOTIFY STOP, OUTAGE STOP, OUTAGESTATUS STOP or with STOP ALL to quit all"
- If the user is opted into only one keyword and sends STOP they will be opted out of all messages on that keyword.
- If the user is opted into multiple keywords and sends "STOP ALL" they will always be opted out of all keywords on that short code.
- Senders using a shared short code cannot change the content of the reply message that is sent in response to the user. Senders who maintain their own dedicated short code or text-enabled toll-free number (TFN) can change the content of the message that is sent in reply to a STOP but cannot change the function.