Question about IPhone 6s T-mobile

[Fahadthelionheart]

Hi, I just want to know if the iPhone 6s t-mobile is fully unlocked? Additionally, i wanna ask u if i can use AT&T SIM card on this tmobile unlocked iPhone.

Thnxx

 

[Bigeric23]

1) Yes, it should be fully unlocked.

2) No, I don't think so.

 

[EmceeGeek]

Yes to both questions.

 

[EricandSuebee]

I thought the iPhones came with a "apple" sim already in them so technically if this is true and you are not on a carrier and you buy the Unlocked T-mobile version you can go with t-mobile or AT&T?