T-Mobile introduces a brilliant new data rollover program

T-Mobile may be an “Un-carrier” but it’s not a charity, it’s here to make money. So while its new Data Stash plans that let customers on capped plans roll over unused data to the next month are good deals for some subscribers, they also come with a side benefit for T-Mobile: They give wireless subscribers an incentive to sign up for more expensive monthly plans.

Remember cell phone plans that “roll over” unused minutes to the next month? T-Mobile US is reviving that strategy for data, but with restrictions. With a new “Data Stash” program announced today, smartphone customers with postpaid Simple Choice plans can keep unused high-speed data after the month is over if they pay for at least 3GB per month. Tablet users get the same perk if they buy at least 1GB of data per month. The offer is not available for T-Mobile’s $50-per-month 1GB Simple Choice plan. Smartphone users who subscribe to that plan will continue to be throttled after they exceed 1GB in any given month, under T-Mobile’s policy of slowing data speeds down instead of charging overage fees. The 3GB plan costs $60 per month.