A regular SMS may contain up to 160 characters. With the add-on Linked SMS you will be able to write
longer text messages than that. Technically speaking you will be able to write a long text message that
during the send process is split up and sent as several text messages, later on to be recombined in the
recipient’s phone where it will appear as one single long SMS. Each concatenated message will be charged
separately.
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Please note that each concatenated text message in a linked SMS is limited to 153 characters due to user-
data headers (UDHs) information that need to be included. Mobile phones use UDH information to enable
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them to link long messages together so that the linked SMS will appear as one single SMS message in the
recipient's phone inbox.

If the linked SMS should contain one or more special characters that are not included in the GSM character
set (03.38), the number of characters per SMS will be limited to 67 (not 153). This is due to the encoding of
the special characters.

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