SIM Card, working Overseas?

[WhitePhoenix5]

I have a Samsung Galaxy SIII, By US Cellular. I have been reading online, about this device being almost impossible to unlock to work with GSM networks within the United States.
Thing is I'm more interested, that it will work Overseas, Using a SIM card from a foreign country.
Will this be automatic? or I have to "unlock" it? Thanks, in advance : )

 

[grumpycompuprof]

If your device is locked to your carrier, then you need to unlock it before you can use another SIM card. If you ask and explain customer service your dile-mma, they may be understanding and give you the unlock code. I had the same issues with ATT and they understood and gave me the unlock code for my htc One. I tried it with a T-Mobile SIM and it works nicely. Overseas here I come.

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