How do I activate T-mobile sim?

[marcelo4527]

I'm thinking about buying a t-mobile sim just to check if my iphone 5 is now in fact unlocked, and I wanted to activate the sim card.
If I get an unactivated sim card from t-mobile, can I just go online and activate it without paying anything (or have to pay for any plans) or do I have to like purchase a prepaid card or sign into a plan that I will have to pay for it?

I'm not planing on using the sim, i just want to activate it

 

[Applejuiced]

You don't need to activate it at all.
Just stick it in and once you see Tmobile pop up on the top left corner you will know its unlocked.
That's what I did to test my unlocks.