So I recently had a conversation with a T-Mobile Customer Service rep via live chat and was told that Unlocked AT&T iPhone 5's will support T-Mobiles LTE. Heres the chat convo below: You have been connected to Raymond A. Me: Will an Unlocked AT&T iPhone 5 work on T-Mobile's new LTE? Raymond A: Hi there! How are you today? Me: I'm fine, how are you? Raymond A: I'm doing great thanks for asking, let me go ahead and check on the compatibility of the iPhone 5 for you Me: Because I heard that you guys will be releasing the new iPhone on April 12, so I was wondering if an AT&T Unlocked iPhone 5 would work. Me: on LTE Raymond A: We have recently come up with an update that yes we'll be able to support iphones this coming April 12, 2013. We would be able to guarantee the functionality of iphones purchased from our T-mobile stores/website however I'm sure your phone should work fine Me: I was reading a blog online and it said that Apple will be releasing a different model for T-Mobile Raymond A: According to our systems I found this message: "To enable LTE for customers using an officially unlocked AT&T iPhone 5 will need to accept an iOS software update, which will enable LTE on the device." Me: different hardware. Raymond A: So its just a matter of software , other than that everything should be great. Me: would I get the same speed as a regular purchased tmobile iphone? Raymond A: The iPhone 5 is equipped with an LTE modem capable of theoretical download speeds up to 100 Mbps Me: I seen 21mbps (AT&T) and 42 Me: for tmobile Raymond A: Yes you would be able to get the said speeds on our largest 4G network. Raymond A: The iPhone 5 will be available online at www.T-Mobile.com, at T-Mobile retail stores and through select dealers and national retail stores for $99.99 down with 24 equal monthly payments of $20 Me: So it totals out to be $579, but if I updated this iPhone via a software update LTE should work fine Raymond A: Correct. Me: and if I upgraded a data plan on this AT&T unlocked iphone 5 Me: it will work on LTE Raymond A: Yes our data plans are now unlimited for the lowest prices available on the market Me: I will have to wait, I'm waiting until the LTE software update is out Me: once it's out, I will call and talk data with you guys. Raymond A: Okay thats definitely understandable. Would there be other inquiries I could answer for you today? Me: no thank you very much raymond. Raymond A: You're welcome I was glad to be of service to you today. Thank you for choosing T-mobile we appreciate your business and have a blessed week. Me: thank you, good bye. Just thought i'd share with you guys wondering. Since I've read blogs / forums saying that LTE for T-Mobile won't work on AT&T models.