Sixt Car Rental Discount Codes, Voucher Codes SE is a European multinational car rental company with about 4,000 locations in over 105 countries. Sixt SE acts as a parent and holding company of the Sixt Group. Sixt is the leading mobility service provider in Germany that aims to provide car rental services throughout Europe. Choose Sixt for renting a car, van or limousine with first-class and innovative mobility service. Enjoy savings on a cheap Sixt rent a car from CarRentals.com. Find quality reviews and Sixt car rental deals for your next trip today.