| Siheung-si Higashihiroshima | Japan Time | 00:00 |
| Siheung-si Hidalgo | Central Time | 15:00 |
| Siheung-si Hillsville | Eastern Time | 14:00 |
| Siheung-si Hilmar | Pacific Time | 17:00 |
| Siheung-si Hill City | Mountain Time | 16:00 |
| Siheung-si Hillarys | Western Australia Time | 01:00 |
| Siheung-si Hijrat Al Harah | Arabian Time | 06:00 |
| Siheung-si Hikkaduwa | India Standard Time | 03:30 |
| Siheung-si Highland Heights | Eastern Time | 14:00 |
| Siheung-si Highnam | United Kingdom Time | 09:00 |
| Siheung-si Highton | Eastern Australia Time | -02:00 |
| Siheung-si Hérémence | Central European Time | 08:00 |
| Siheung-si Heringsdorf | Central European Time | 08:00 |
| Siheung-si Henrico | Eastern Time | 14:00 |
| Siheung-si Hepburn Springs | Eastern Australia Time | -02:00 |
| Siheung-si Hephzibah | Eastern Time | 14:00 |
| Siheung-si Henndorf am Wallersee | Central European Time | 08:00 |
| Siheung-si Herodsfoot | United Kingdom Time | 09:00 |
| Siheung-si Hessle | United Kingdom Time | 09:00 |
| Siheung-si Herve | Central European Time | 08:00 |
| Siheung-si Herrin | Central Time | 15:00 |
| Siheung-si Hershey | Eastern Time | 14:00 |
| Siheung-si Herrera de Pisuerga | Central European Time | 08:00 |
| Siheung-si Heguri | Japan Time | 00:00 |
| Siheung-si Heftziba | Israel Time | 07:00 |
| Siheung-si Heidenheim | Central European Time | 08:00 |
| Siheung-si Heimenkirch | Central European Time | 08:00 |
| Siheung-si Hendersonville | Eastern Time | 14:00 |
| Siheung-si Hemmadi | India Standard Time | 03:30 |
| Siheung-si Helen | Eastern Time | 14:00 |
| Siheung-si Helmsley | United Kingdom Time | 09:00 |
| Siheung-si Haymarket | Eastern Australia Time | -02:00 |
| Siheung-si Haymarket | Eastern Time | 14:00 |
| Siheung-si Hayti | Central Time | 15:00 |
| Siheung-si Hazelwood Park | Central Australia Time | -01:30 |
| Siheung-si Hazlehurst | Eastern Time | 14:00 |
| Siheung-si Headingley | Central Time | 15:00 |
| Siheung-si Headland | Central Time | 15:00 |
| Siheung-si Healdsburg | Pacific Time | 17:00 |
| Siheung-si Hebden Bridge | United Kingdom Time | 09:00 |
| Siheung-si Heber Springs | Central Time | 15:00 |
| Siheung-si Heath | Central Time | 15:00 |
| Siheung-si Heathmont | Eastern Australia Time | -02:00 |
| Siheung-si Heathridge | Western Australia Time | 01:00 |
| Siheung-si Hayden | Pacific Time | 17:00 |
| Siheung-si Hawthorn | Eastern Australia Time | -02:00 |
| Siheung-si Hawthorn East | Eastern Australia Time | -02:00 |
| Siheung-si Hawaiian Paradise Park | Hawaii-Aleutian Time | 19:00 |
| Siheung-si Hawera | New Zealand Time | -04:00 |
| Siheung-si Hawes | United Kingdom Time | 09:00 |