How do I tell if there is a Sim lock on my Samsung note 3

[AC Question]

Imy not sure if another carrier Sim card will work or if it has to be t-mobile

 

[Count Chokula]

Here you go:
http://visihow.com/Know_if_an_Android_Phone_Has_Been_Unlocked

You might also want to consider unlocking your phone. There are a host of unlocking services on the internet to choose from. It's a great way to "free up" your phone so that you can use it with any provider.

 

[hallux]

There shouldn't be a need for an unlocking service. If the device is paid off and the account in good standing, T-Mobile should be able to help with unlocking the device if it's needed.