| Postal Code Place Name | Élancourt |
| Region | Île-de-France |
| Department | Yvelines |
| Arrondissement | Rambouillet |
| Canton | Trappes |
| Current Time: | CET |
| Time Zone: | Central European Time |
| IANA Time Zone: | Europe/Paris |
| Dialing Code: | 01 |
| 78190 Trappes |
| 78310 Maurepas |
| 78320 La Verrière |
| 78370 Plaisir |
| 78760 Jouars-Pontchartrain |