SMS API

SMS Messages

The SMS API can send SMS messages worldwide. SMS messages are text only and do not support media attachments. Use MMS if you want attachments.

To send an SMS, use the SendMessage method.

Message Length

The API will automatically split messages into fragments when longer than certain limits. The maximum SMS fragment length depends on the settings specified in the SendMessage request. Note that spaces are included in the character count.

  • If IsUnicode = False and Concatenate = True, the max message length is 153 characters.”)
  • If IsUnicode = False and Concatenate = False, the max message length is 160 characters.
  • If IsUnicode = True and Concatenate = True, the max message length is 67 characters.
  • If IsUnicode = True and Concatenate = False, the max message length is 70 characters.

Fragmentation is a standard part of SMS messaging. All U.S. carriers limit their text messages to 160 characters in length.

Messages from Canadian carriers vary from 136 to 160 characters in maximum length. Esendex sends to Canada the same way as the U.S. To ensure complete message delivery, Esendex advises that your application only send messages to Canadian recipients in 136-character increments. If the message is longer than 136 characters, the best practice is to split the message on your application side at the 136-character mark; this will prevent data loss that may occur from Canadian carriers that truncate anything over 136 characters.

Message Concatenation

A series of message fragments is not the best experience for your recipients. Use text message concatenation to reunite the fragments of long messages on your recipients’ devices. To send concatenated messages set the Concatenate parameter to true in the SendMessage method.

The number of concatenated messages a recipient can receive is dependent upon the recipient’s carrier. The API itself does not limit the number of concatenated messages.

Unicode Support

If your SMS message includes certain special characters (such as emoji), you should send your message using Unicode. By default, Unicode is disabled. With Unicode disabled, SMS API supports Latin-9 (ISO/IEC 8859-15) encoding.

To send Unicode messages set the IsUnicode parameter to true in the SendMessage method. SMS API supports UTF-16.

Let’s start sending, together.