Virgin Mobile Unlimited Plan Not So Unlimited Anymore

Virgin Mobile’s unlimited 3G data service may not be as appealing to customers next month, as the service will be soft-capped at 5 GB per billing cycle starting February 15. PC Magazine received confirmation of the upcoming changes to Virgin Mobile’s Broadband2Go prepaid service which is currently available for use with either a MiFi mobile hotspot device or a USB data stick. Once users hit the 5 GB cap, Virgin Mobile will reduce speeds of the 3G data connection until the next billing cycle begins.

When Virgin Mobile rolled out its unlimited Broadband2Go service in August, we pointed out the value of the no-contract, $40 per month offering for unlimited service, which is provided on Sprint’s (s s) 3G network. At the time, the deal was half the price of comparable prepaid service from Verizon (s vz). And now, just six months later, the “unlimited” nature of the plan will be capped by speed throttling, the same method T-Mobile implemented last April for its data plans.

The Virgin Mobile plan change in the U.S. follows a modification from T-Mobile UK earlier today, which cut its “unlimited” 1 GB monthly plan in half. At this point 3 is the only mobile broadband provider in the UK testing the unlimited data plan waters while here in the U.S., only Sprint, and it’s WiMAX partner Clearwire (s clwr), offer all-you-can-use data plans among the largest carriers. With such unpredictable variances in data demand, combined with the number of mobile broadband subscribers about to surpass wired subscribers around the globe, it’s clearly becoming a challenge for any provider to offer truly unlimited mobile data.

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