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Multi Part Messages & Concatenation

Message Length - Introduction

Each SMS has a message length of 160 characters. If the character limit is exceeded then the following limits for messages are considered.

Standard GSM 03.38 Character Set

Single text messages are limited to 160 characters, including spaces.

The maximum length of two-part or three-part multi-part text messages is 306 (2 x 153) and 459 (3 x 153) characters, respectively.

One can send up to 1000 characters as multi-part message which will be split into 7 messages internally. This refers only to messages that contain the standard GSM 03.38-character set.

Each multi-part text message is limited to 153 characters rather than 160 due to the need for user-data headers (UDHs) information.

Mobile phones use UDH information to enable them to link long messages together so that they appear as single SMS messages in recipient’s phone inbox.

Number of SMS
Number of characters in the linked SMS


160 characters


306 (2x153 characters)


459 characters (3 x 153)




3978 characters (26 x 153)

Concatenate 4000 characters

After 26th SMS, the 27th SMS is concatenated to 4000 characters. An addition of 22 characters can be accommodated post the 26th SMS.

Unicode Characters

Using Unicode, for languages such as Hindi, restricts your message to a maximum of 70 characters per SMS. You can, however, send longer text messages, with our system splitting them into two or at the three separate text messages.

The maximum lengths of two-part and three-part multi-part Unicode text messages are 134 (2 x 67) and 201 (3 x 67) characters, respectively. You could send up to 500 characters as multi-part message which will be split into 8 messages internally.

Number of SMS
Number of characters in the linked SMS


70 characters


134 characters (2 x 67)


201 characters (3 x 67)




2010 characters (29 x 67)