How does STOP work on a Toll-Free number?

When a mobile subscriber texts in the keyword STOP to a toll-free number (TFN), the STOP response is enforced by the network. This means that the end user will receive a network message in reply that says ""NETWORK MSG: You replied with the word "stop" which blocks all texts sent from this number. Text back "unstop" or "start" to receive messages again." 

Any further messages to the subscriber from the TFN will be automatically blocked at the network level, until the end user texts in START or UNSTOP. Network-managed opt-in/out is also supported in the French language (i.e. ARRET/NONARRET).

We will pass on the inbound STOP message from the end user to you, so you can take action to update your subscriber lists and stop messaging the subscriber. If you send a message from a TFN to a subscriber that has opted out, you will receive error code 257 "User opted out (STOP)" from Sinch. 

All TFN error codes can be found here.

Product Information

Learn more about Toll-Free Numbers from Sinch.