Poissy is located in Paris city, France at the 48.929, 2.0495 coordinates. Distance from Poissy to other cities. are listed below, click on the city name to find distance between. Distance from Poissy to Cergy-Pontoise 12 km, to Saint-Quentin-en-Yvelines 18 km, to Boulogne-Billancourt 18 km. The green marker indicates the location of Poissy.