Which lumia 830 will work on both AT&T LTE AND T-mobile LTE?

[Windows Central Question]

The 830 is a phone that I've wanted for awhile. Given that new phones are coming out, dishing out money for a flagship is too much. I have AT&T now but will be switching to t-mobile. Which one of the 830s needs to be purchased so that I can seamlessly change from one carrier to the other without losing LTE if possible? I apologize if this question has already been asked but I've been searching for days and cannot get a straight answer.

 

[libra89]

Do you have the AT&T variant of 830? If you do, you have to unlock that one first before using it on t-mobile, but it looks like you can use it on T-mobile according to their website.

If you are looking to buy an unlocked device altogether, I believe it should if you buy one from bhphotovideo.com since comments have said that they have the bands that work with both AT&T and T-mobile. Nokia Lumia 830 RM-985 16GB Smartphone A00021288 B&H Photo Video