Should there be any issue with this?

[Kauai]

Wasn't really sure where to post this, but any way.

My Mom is going to sign up for a new T-Mobile account soon and planned to get an iPhone. Since she isn't big on tech I'll be giving her my like-new condition iPhone 5 and she'll be getting a Note 3 at T-Mobile for me, since I really like the screen size and phone overall from having used it before.

My iPhone 5 is AT&T. Should there be an issue with her getting the Note and us swapping out the sim cards between the phones?

Thanks!

 

[LIVEFRMNYC]

Well you'll need to unlock both phones.

 

[Lloydbm41]

Well you'll need to unlock both phones.

On top of this, the OP should read this: http://www.cnet.com/8301-17918_1-57576459-85/bringing-phones-to-t-mobiles-lte-network-the-devils-in-the-details/