There are more than a few reasons why people choose to get their devices from a carrier but then again, that means you device will be bound to them unless you figure out how to unlock it on your own. If you still own a Samsung Galaxy Note 3 that is still locked, here is how you can unlock your device with the help of the leaked code.
Start by putting in a new SIM card in the Samsung Galaxy Note 3. Restart the device and key in the code *#197328640#. Now select  UMTS >  Debug Screen >  Phone Control >  Network Lock > Options  Perso SHA256 OFF.
You will need to wait for 30 seconds before selecting back to enter the main menu. From there, you should see “Network Lock”, select  NW Lock NV Data INITIALLIZ. Your Samsung Galaxy Note 3 should be unlocked now.
There were reports that the code also worked on some of the other Samsung smartphones as well.