The Citroën C6 is an executive car produced by the French car maker Citroën since 2005. The Citroën C6 was inspired by the Citroën C6 Lignage concept car with a fastback saloon like styling.

Executive car is a British term for a large car which is equivalent to the European E-segment and American full-size classifications. Executive cars are larger than compact executive cars, and smaller than luxury saloons / full-size luxury sedans.