Kogan Mobile is 100% prepay, meaning that you select and pay for the service that suits you most in advance.
This also means you don't need to worry about remembering to pay bills at the end of the month!
The total data amount in each Prepay Plan is split into 30-day blocks and has a 30-day expiry. If you run out of data on a Prepay Plan before the end of the 30-day block, you can add a Data Pack Add-On to tie you over to the next 30-day block. Data Pack Add-Ons for Prepay Plans will expire in 30-days, or when the allocated data has been exhausted.