The Citroën C1 is a city car produced by the French manufacturer Citroën since June 2005. The C1 was developed as part of the B-Zero project by PSA Peugeot Citroën, in a joint venture with Toyota.

The Peugeot 107 is identical to the C1, other than the front bumper and front and rear lights, while the Toyota Aygo is slightly more differentiated, but still obviously similar like its Asian made facelifted Yaris hatchback and sedan and facelifted third generation Vios.

All of them are built at the new facilities of the TPCA joint venture (Toyota Peugeot Citroën Automobile) in the city of Kolín, Czech Republic. The project was presented for the first time at the 2005 Geneva Motor Show. The cars are four seater, three door or five door hatchbacks measuring 3.40 metres (133.9 in) in length. The body was designed by Donato Coco.