There are certain benefits when you buy a smartphone from a carrier. It is definitely easier on the wallet but that also means that your phone will be locked to the carrier and while others do not mind having their smartphone locked other might find it a little inconvenient.
Of course, you can always get the carrier to unlock it for you when your contract ends but some of you might want to free it before the contact ends. The good news is that you can now do it on your own as well.
First, get the unlock SIM code from your carrier. You will need to dial #06# on your Samsung Galaxy S6 to get your IMEI number. Next, call your carrier and ask them for the SIM unlock code for the Samsung Galaxy S6.
You might need to say that you are going to travel and that you will need the phone unlocked. Provide them with your IMEI number and they will generate a code for you. Once you receive the code, use that to free your Samsung Galaxy S6.