That is actually quite easy to check if you have transferable free supercharging and there are 2 flavors there:
1. Call Tesla support and ask them for the SC code for your car. If it is SC01 you have transferable lifetime free supercharging, SC05 is free SC for the current owner and not transferable, SC02 to SC04 are not transferable and not free.
or 2:
Go to your Tesla account and to your vehicle page. Then click on details (below the VIN number), which will give you a pop-up screen with your car details. It will probably say free supercharging there or something else.
To find out if you have SC01 (free transferable lifetime supercharging) or another SC code you need to see the html source code of the page with the pop-up (there are good guides for this depending on which browser you use). Do a search in the source code for SC0 and you will see which SC code you have, hidden between all the other options for your car.
1. Call Tesla support and ask them for the SC code for your car. If it is SC01 you have transferable lifetime free supercharging, SC05 is free SC for the current owner and not transferable, SC02 to SC04 are not transferable and not free.
or 2:
Go to your Tesla account and to your vehicle page. Then click on details (below the VIN number), which will give you a pop-up screen with your car details. It will probably say free supercharging there or something else.
To find out if you have SC01 (free transferable lifetime supercharging) or another SC code you need to see the html source code of the page with the pop-up (there are good guides for this depending on which browser you use). Do a search in the source code for SC0 and you will see which SC code you have, hidden between all the other options for your car.