The way we buy mobile data is pretty unusual, if you think about it. Unlike other utilities, like water and electricity, we're asked to estimate our usage in advance, and what we don't use, we lose. Worse still, if we underestimate our usage we might get slugged $10 for an auto data top-up.
It's no wonder that data rollover is a feature we're often asked about. In Australia it's difficult to find plans that let you carry unused data from one month into the next month, but it's not impossible. Here are some of the best.