If you are leaving Switzerland to take your residence abroad with your car, you have to return your Swiss number plates (licence plates) as well as your Swiss vehicle registration document to the road traffic office of your previous Swiss place of residence immediately after your arrival abroad. You can also hand them over to the Swiss representation that covers your new place of residence abroad.
Certificate of nationality and registration in the register of the Swiss Abroad
You must send your application for a local vehicle registration document and number plates directly to the competent authority in your new country of residence.