Check your remaining data and text message usage
1. Dial *DATA# (*3282#) on your phone.
2. Press the Send key.
3. Within seconds, a breakdown of your remaining data usage will be delivered via text message to your phone screen. The remaining data usage will be broken down by type.
This will let you know the number of text messages that you have left, but it is important to be aware that this can be behind by a couple of days (and usually is). It is a useful tool to get a rough idea of where you are on your usage.