SMS Parts and Character Counts

7-bit or GSM encoding 

7-bit or GSM encoding is the most commonly used encoding for SMS. 

You can view the basic character set for GSM 7-bit default alphabet here. The characters in the basic character set are counted as 1 character when sent in an SMS. 

The following characters are part of the basic character set extension, and are counted as 2 characters each when sent in an SMS.

| ^ € { } [ ] ~

If a message has more than 160 characters, it becomes a multi-part SMS message in 7-bit (GSM) and the maximum length per SMS part will change. See What are multi-part SMS messages?

Unicode Encoding

Unicode (UCS-2) encoding supports more set of characters and languages compared to 7-bit or GSM encoding.

When your message has at least one character that is not listed in the 7-bit or GSM encoding, UCS-2 encoding is automatically used. In this case, each message takes more space, and the maximum length of 1 SMS message is reduced to 70 characters.

If a message has more than 70 characters, it becomes a multi-part SMS message in unicode encoding and the maximum length per SMS part will change. See What are multi-part SMS messages?

What are multi-part SMS messages?

When the message length exceeds the SMS character limit of 160 characters for GSM encoding or 70 characters for UCS encoding, the message is split up into multiple separate SMS parts. 

Each SMS part is sent to the recipient device separately. 

For multi-part SMS messages, each SMS part has a different maximum character count calculation than regular SMS.