It seems unlimited data offering plans are a prized commodity these days. T-Mobile, whose spot is at the bottom when it comes to mobile plan comparisons, just announced its new unlimited data plan – but it comes with some, well, limits.

As part of its new “Value” plans, T-Mobile is offering what they call “flexible pricing,” meaning customers pay for the high-speed data that they need. While it’s technically unlimited in the sense that you’re only using what you need, there are some data caps. While you’ll never pay for an overage (thank goodness), you will get bumped to a slower data rate. It’s kind of good, but it’s kind of not the idea behind an unlimited data plan.

Value plans from T-Mobile will offer 2 GB, 5 GB or 10 GB of high-speed data — with no data overage charges. Customers can choose from a variety of monthly plans and only pay for the high-speed data they need.

“T-Mobile is committed to making the always-on benefits of smartphones and tablets more accessible and worry-free for all Americans,” said John Clelland, senior vice president of marketing at T-Mobile USA in a press release. “Customers want to enjoy all that the mobile Web has to offer, but they don’t want to pay for more than they need or worry about bill shock. Our incredible value comes from the combination of our nationwide 4G network, exceptional device portfolio and affordable plans that offer unlimited data access without overages.”

T-Mobile’s new Value family plan with unlimited talk, unlimited text and unlimited data with 2 GB of high-speed data is just $49.99 per line for two lines.

This bit of strategic marketing makes companies like Verizon Wireless look bad. Big Red recently retired its unlimited data plans for new customers, its cheapest plan starts at $30 USD/month for 2 GB of data.

Verizon charged $30 for unlimited data, but now 5GB will run you $50, 10GB $80 and anything over will run $10 per GB. The closest one could get to unlimited would be the hefty 10GB plan and, even then, it will cost three times as much.

Since unlimited minute plans can be rather costly, using data and texts to communicate became the primary method for many to communicate. As a result, there has been slight decline in the price of calling plans and a move away from unlimited data. By placing data caps each month and charging more for each greater tier, carriers make more money and relieve some of the pressure from their network.

By comparison, Verizon Wireless’ tiered data plans will be the most expensive and there are no smaller plan offerings, which might mean less new customers.

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