Concatenated SMS messaging
When you need to say more than 160 characters allow
Standard SMS (short message service) messages are 160 characters in length. For most purposes this is sufficient, but occasionally you may need to send a longer message, which is where concatenation comes in.
Concatenated SMS allows the length of an SMS to be extended by combining multiple SMS together so that they are displayed as a single message on the recipient's phone.
Sign-Up.to supports concatenation of up to 3 SMS messages, allowing a maximum message length of 459 characters. This is done automatically when you create a message that exceeds 160 characters - an on screen warning will notify you when this happens.
When concatenation is used a small part of each SMS is used to facilitate the process, so the actual number of characters per part is reduced from 160 to 153. As multiple SMS are used to create a concatenated message the cost of delivering the message is multiplied by the same amount, so a message which is 2 SMS long costs twice as much to send as a message which is only a single SMS in length.