| Grenchen Ramadan | Uzbekistan Time | -03:00 |
| Grenchen Wayville | Central Australia Time | -07:30 |
| Grenchen Ramanattukara | India Standard Time | -03:30 |
| Grenchen Wayzata | Central Time | 07:00 |
| Grenchen Ramanathapuram | India Standard Time | -03:30 |
| Grenchen Weaverville | Pacific Time | 09:00 |
| Grenchen Ramingstein | Central European Time | 00:00 |
| Grenchen Webbers Falls | Central Time | 07:00 |
| Grenchen Rambukkana | India Standard Time | -03:30 |
| Grenchen Webster | Central Time | 07:00 |
| Grenchen Xuchang | China Time | -06:00 |
| Grenchen Yermo | Pacific Time | 09:00 |
| Grenchen Xuzhou | China Time | -06:00 |
| Grenchen Yeroskipou | Eastern European Time | -01:00 |
| Grenchen Yaliyuru | India Standard Time | -03:30 |
| Grenchen Waverley | Eastern Australia Time | -08:00 |
| Grenchen Yallabatharra | Western Australia Time | -06:00 |
| Grenchen Waupaca | Central Time | 07:00 |
| Grenchen Yallambie | Eastern Australia Time | -08:00 |
| Grenchen Wauchope | Eastern Australia Time | -08:00 |
| Grenchen Wayne | Eastern Time | 06:00 |
| Grenchen Wavre | Central European Time | 00:00 |
| Grenchen Watkins Glen | Eastern Time | 06:00 |
| Grenchen Watkinsville | Eastern Time | 06:00 |
| Grenchen Watertown | Eastern Time | 06:00 |
| Grenchen Watson | Eastern Australia Time | -08:00 |
| Grenchen Wattwil | Central European Time | 00:00 |
| Grenchen Wasserburg am Inn | Central European Time | 00:00 |
| Grenchen Waterloo | United Kingdom Time | 01:00 |
| Grenchen Waterford | Eastern Australia Time | -08:00 |
| Grenchen Waterford Township | Eastern Time | 06:00 |
| Grenchen Warrenton | Central Time | 07:00 |
| Grenchen Warrington | Eastern Time | 06:00 |
| Grenchen Warsaw | Eastern Time | 06:00 |
| Grenchen Wasaga Beach | Eastern Time | 06:00 |
| Grenchen Washington | Eastern Time | 06:00 |
| Grenchen Washington | Eastern Time | 06:00 |
| Grenchen Wasilla | Alaska Time | 10:00 |