Change Time Zone on iPhone is easiest when you use the iPhone feature that directly controls the task instead of changing several unrelated settings.
- Open Settings > General > Date & Time.
- Turn off Set Automatically if you need to choose a time zone manually and the control is available.
- Tap Time Zone.
- Search for and select the desired city or time zone.
- Check the displayed time and calendar after the change.
If Set Automatically is unavailable, Screen Time restrictions, carrier settings, location settings, or device management may control it. Automatic time is usually the safest choice for normal use.
Time zone changes affect displayed local times for calendars and clocks, but calendar events can also have their own time-zone behavior. After traveling or changing the setting manually, verify upcoming appointments rather than assuming every event shifted as intended.
When finished, verify the result in the app or setting you changed before making additional adjustments.