Over the weekend, AT&T announced a promotion on its biggest and priciest family plans for data: during October, they will double the amount of data that users on most expensive plans, starting at the 15 GB tier, get with their monthly plan. “Oh, yeah?” said competitor Sprint. “We’ll DOUBLE their double data!”

The root of this data one-upmanship is Sprint’s normal goal to offer customers twice as much data for the same price that AT&T or Verizon charges for a shared data pack.

If you sign up for AT&T between now and October 31, the promotion starts with the plan that would normally give you 15 GB of data per month for $130. Now customers get 30, which AT&T says will last for as long as you want to keep that plan. Over at Sprint, $130 gets you 60 GB of data, and so on up the line.

There is, of course, always a catch. Over at AT&T, the catch is that you either bring your own device, pay full price for your device, buy your phone on installments using the Next program, or pay an extra $15 per device per month bought with a carrier subsidy for access to the Mobile Share plan.

At Sprint…we can’t see any glaring issues with the promotion, but at this point Sprint is desperate to regain customers, especially the high-value, data-slorping customers who are willing to pay for big plans that start at $130.

Sprint doubles AT&T’s double-the-data wireless promotion [CNET]

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