Following rumors earlier this week that they would do so, Virgin Mobile has announced this morning that they will begin offering Apple’s iPhone 4S on their prepaid wireless network. The iPhone 4S and iPhone 4 will be available to Virgin Mobile customers on June 29. There will be a variety of rate plans available to Virgin Mobile iPhone customers, all with unlimited texting and unlimited data (though their “fair use policy” means that “unlimited” actually means 2.5GB). Plans start at $30 for 300 voice minutes per month, $40 for 1,200 minuutes, and $50 for unlimited minutes (though that price includes a discount that you get when you let Virgin bill your credit card monthly).

Virgin Mobile is the second prepaid wireless carrier to announce that they would be offering the iPhone. Cricket Wireless announced last week that they would begin offering the iPhone on June 22. Rumors that Boost Mobile would do the same have not been confirmed.

Just like Cricket, Virgin Mobile will be offering the iPhone without contract or activations fees. That, of course, means no carrier subsidies, which means that an iPhone 4S will cost you $649 up front. Savings on the rate plan, though, more than make up for the heftier iPhone price tag.

For more information, you can check out Virgin Mobile’s website.