HomeFranceÎle-de-FranceGuyancourtGuyancourtÎle-de-France, FranceGuyancourt, Île-de-France, France: 18 postal codes.Postal codes of Guyancourt78041 CEDEX78042 CEDEX78043 CEDEX78044 CEDEX78045 CEDEX78046 CEDEX78047 CEDEX78048 CEDEX78049 CEDEX7828078282 CEDEX78283 CEDEX78284 CEDEX78285 CEDEX78286 CEDEX78287 CEDEX78288 CEDEX78289 CEDEX