In the cellular phone industry, mobile phones and their networks sometimes support concatenated short message service to overcome the limitation on the number of characters that can be sent in a single SMS text message transmission.

How do I send a concatenated SMS?

Sending a concatenated SMS using a User Data Header. One way of sending concatenated SMS (CSMS) is to split the message into 153 7-bit character parts (134 octets), and sending each part with a User Data Header (UDH) tacked onto the beginning.

What happens if you send a text over 160 characters?

When you send an SMS Message longer than 160 characters, the message will be concatenated and split into 153 character chunks. The 1st 7 characters of each message are used to instruct the carriers and your handset to concatenate the message and re-build it into one fluent long message upon delivery.