Buying an unlocked AT&T iPhone 6s - do I need a SIM card?

[macrumorsuser10]

Hi, I have an iPhone 5 with AT&T grandfathered unlimited. I currently pay $63/month from my last 2-year contract, which expired around January of this year (2015). I live in California.

Question:

I want to buy an unlocked AT&T iPhone 6s. Will I need a new SIM card, or do I just put my current iPhone 5 phone's SIM card into the new 6s?

Thanks.

 

[Shadowbech]

No you will not need a new sim, and you can just put your sim from your iPhone 5 into your new 6S as it will still be nano.