| Nagano Cimadolmo | Central European Time | 07:00 |
| Nagano Ciney | Central European Time | 07:00 |
| Nagano Chuo | Japan Time | 00:00 |
| Nagano Cifuentes | Central European Time | 07:00 |
| Nagano Cidade Ocidental | Brasilia Time | 12:00 |
| Nagano Cetona | Central European Time | 07:00 |
| Nagano Český Krumlov | Central European Time | 07:00 |
| Nagano Cervantes | Western Australia Time | 01:00 |
| Nagano Cerovlje | Central European Time | 07:00 |
| Nagano Choudrant | Central Time | 14:00 |
| Nagano Christies Beach | Central Australia Time | -00:30 |
| Nagano Chukai | Malaysia Time | 01:00 |
| Nagano Chryston | United Kingdom Time | 08:00 |
| Nagano Chotebor | Central European Time | 07:00 |
| Nagano Cala Ferrera | Central European Time | 07:00 |
| Nagano Cala Millor | Central European Time | 07:00 |
| Nagano Calaf | Central European Time | 07:00 |
| Nagano Calvi | Central European Time | 07:00 |
| Nagano Calolziocorte | Central European Time | 07:00 |
| Nagano Caloocan | Philippine Time | 01:00 |
| Nagano Calistoga | Pacific Time | 16:00 |
| Nagano Califon | Eastern Time | 13:00 |
| Nagano California | Eastern Time | 13:00 |
| Nagano Calimesa | Pacific Time | 16:00 |
| Nagano Caldes d'Estrac | Central European Time | 07:00 |
| Nagano Calbe | Central European Time | 07:00 |
| Nagano Cene | Central European Time | 07:00 |
| Nagano Central City | Mountain Time | 15:00 |
| Nagano Centralia | Eastern Time | 13:00 |
| Nagano Central Jakarta | Western Indonesia Time | 02:00 |
| Nagano Céret | Central European Time | 07:00 |
| Nagano Cercedilla | Central European Time | 07:00 |
| Nagano Celano | Central European Time | 07:00 |
| Nagano Cedar Springs | Eastern Time | 13:00 |
| Nagano Ceelbuur | East Africa Time | 06:00 |
| Nagano Celebration | Eastern Time | 13:00 |
| Nagano Celina | Central Time | 14:00 |
| Nagano Cellefrouin | Central European Time | 07:00 |