Data banking allows you to keep your unused data each month! Let’s say you are on our 40GB mobile plan - in this case, you would start your monthly cycle with 40GB of data. At the end of the month, you’ve only used 20GB of your allocated data. Instead of losing the remaining 20GB of mobile data, it will effectively get added to your "bank" for when you need it. You would now have a total of 60GB of data (40GB for this month + 20GB of "banked" data from last month). The amount of data you can bank varies depending on your plan.