Nokia Lumia 521 Quick Manual page 18

If you change to a new Windows Phone device,
you can get your messages to your new phone
during the setup.
You can send text messages that are longer
than the character limit for a single message.
Longer messages are sent as two or more
messages. Your service provider may charge
accordingly. Characters with accents, other
marks, or some language options, take more
space, and limit the number of characters that
can be sent in a single message.
Using services or downloading content may
cause the transfer of large amounts of data,
which may result in data costs.
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