These snappy little numbers are shared or dedicated 4 or 5 digit numbers that users text details to (classic example text 'vote' to 8861). They are used for larger campaigns, so if you have a larger volume of messages to deliver, this may be the option for you.

They are also used as a revenue generator (SMS reverse billing).

Your customers are charged a premium on top of their standard mobile charge for SMS; you receive a premium from their mobile phone network provider.

SMS reverse billing has traditionally been used as a convenient way to pay for information services and competition entries. Reverse billing is a viable alternative to credit cards when dealing with low value transactions. It allows for automated payment systems which can be integrated into a website or be operated in a completely remote location.