T-Mobile announced new data plan add-ons that will give subscribers access to unlimited data without speed caps for the first time on the carrier's networks.

T-Mobile began offering "truly unlimited" data plans for UK customers in January, but despite the carrier claiming otherwise, rumors persisted that data speeds were being throttled once users reached a certain level.

Now T-Mobile promises to eliminate data speed caps for users willing to pay a little more with its "Unlimited Nationwide 4G Data" scheme, set to become available on Sept. 5.

Truly a good deal?

With the new unlimited 4G data add-on, T-Mobile customers will have access to 4G speeds of up to 42MB per second, no matter how much they download on their devices.

The new "Unlimited Nationwide 4G Data" comes in the form of an add-on to T-Mobile subscribers' existing plans, at $20 per month for "Value" plan users without a phone subsidized directly from the carrier, and $30 for everyone else.

That brings the cost up to $89.99 for unlimited voice, text and data, which, as T-Mobile pointed out, compares favorably with Sprint's similar $109.99 unlimited, no-caps plan.

And T-Mobile's rates seem especially nice when compared with the direction other carriers are going, like AT&T's new "data bucket" plans, which rack up costs the more data subscribers want to use.

Fool us once...

The introduction of "truly" unlimited data plans leaves only one catch, though it's a big one for anyone hoping to take advantage of their newly unthrottled T-Mobile plan with a connected laptop or other device: tethering still won't be supported.

T-Mobile users who rely on mobile hotspot capabilities will have to subscribe to a more traditional plan, as the new Unlimited Nationwide 4G Data add-on will not allow for tethering.

At least the unlimited data plans aren't likely to go away once T-Mobile's 4G LTE network heats up - a spokesperson was quoted in a published report that they're not "promotional," implying that they're here to stay.

Via The Verge