In some devices the message type gets converted from SMS text message to MMS multimedia message if the message length exceeds the device-specific setting which is typically 5 - 10 SMS submessages (around 760-1520 characters). If the message is longer, it is converted to MMS to avoid potential issues in handling long text messages in the recipient device. The cost of a SMS message consisting of several concatenated submessages may also be higher than the cost of a single MMS message.
The conversion from SMS text message to MMS multimedia message occurs when the automatic message type is selected in the message options. This is the default mode where the device tries to automatically select the best mode for the message.
The conversion from SMS to MMS can be avoided by selecting Options > Sending options > Message type > Textwhen in the Text message window writing the message. The message is then always sent as SMS text message and no conversion to MMS occurs.
The maximum number of concatenated SMS submessages can be up to 10 (around 1520 characters). In multimedia mode the message length can be longer.
