(Note- Samsung GS3 can’t be used for GSM service as its CDMA only)
Sprint will generally unlock phones if you specify you are traveling outside the US for a significant period of time. They are against unlocking phones for use with other US companies (regionally unlocking the phone).
What do you need to get your phone internationally unlocked?
– The device can be unlocked
– The account holder is requesting the unlock
– The account has been active for 90+ days
– You have not unlocked another device in the past year
– There is no balance on the phone purchase
Contact international customer care via chat oremail from sprint.com/wwwsupport or call 888-226-7212.