Are all carrier models the same except for the sim card?

[LittlePixels]

I want to get an unlocked iPhone 6 Plus and use it on AT&T. As far as I can see, the only way to preorder an unlocked phone is to get the T-Mobile version. I know when I bought my cellular iPad last fall, I found out they were all the same, just that they came with a carrier specific sim that could be swapped for one from whatever carrier you wanted. Is this the case with the iPhones too? Can I use my AT&T sim in a T-Mobile iPhone? I tried chat help on Apple.com first, but they were unable to answer this for me.

 

[Danny Olivo]

Good question, I'll be watching for answers on this as I want to do the same.

 

[kellyp513]

Last year I bought the T-Mobile version of the 5S and used it with my AT&T SIM card.

 

[LittlePixels]

Does it get LTE speeds on AT&T? Any other issues?

 

[Danny Olivo]

What's the difference between the two phones ? Are they exactly the same depending on what sim you put in it ?

 

[iTechHead]

I had a T-Mobile 5s factory unlocked and everything worked fine with At&t. The guy at the store set me up with a new nano Sim and I was out the door with LTE working just fine.