T-Mobile continues to push other carriers to innovate services.
As we often see, the companies who respond to original creations come up with slightly different offers and in this case the AT&T plan at first appears to be the better deal. T-Mobile requires that you subscribe to at least a 3GB data plan while AT&T is offering rollover data for all subscribers with a Mobile Share Value plan.
However, AT&T's rollover data expires after one billing cycle while T-Mobile's data stash can be used at any time in the next 12 months.
Rollover data is a nice benefit for existing AT&T subscribers, but isn't a benefit worth switching carriers for.
T-Mobile doesn't have shareable data as it focuses on individual data allocations so there is a major difference in how data is managed and consumed. AT&T's offering lets you rollover any leftover data in your shared plan and that rollover data can be used by anyone on that shared plan.
Qualified AT&T Mobile Share Value plan customers don't have to do anything to get this offering, it will appear automatically starting 25 January.
Just like their previous rollover minute plan (prior to unlimited calling plans), your plan allotment is consumed first, followed by your unused rollover data.