The fastest way depends on your phone type

On most phones, the time updates automatically from your carrier or internet connection. If you need to change it manually — because you've crossed time zones, your phone is stuck on the wrong time, or you're setting up a new device — the steps differ between iPhone and Android.

For an iPhone, go to Settings, tap General, then Date & Time. Toggle off "Set Automatically" if it's on, then tap the time display to change the hour and minute. For Android, the path is Settings, then System (or About Phone on some models), then Date & Time. Turn off "Automatic Date & Time" and tap "Set Time" to enter the correct time manually.

Both systems will let you change the time zone separately from the clock time itself, which matters if you've moved to a different region. The time zone setting is usually just below the time adjustment option on the same screen.

Key Takeaways

  • Most phones set the time automatically and do not need manual adjustment unless the automatic setting fails or you cross time zones.
  • On iPhone, open Settings > General > Date & Time and toggle off "Set Automatically" before you can change the time.
  • On Android, go to Settings > System > Date & Time and turn off "Automatic Date & Time" to adjust the clock manually.
  • If your phone keeps reverting to the wrong time after you change it, turn off automatic updates and check that your time zone setting matches your location.

Why your phone might show the wrong time

If your phone's time is wrong even though you haven't touched the settings, the automatic update feature is usually the culprit. Your phone pulls the time from your cellular network or Wi-Fi connection, and if that source is incorrect, your clock will be too. Restarting your phone or toggling airplane mode on and off for a few seconds often forces a fresh time sync.

A phone that's been off for weeks or months may also have drifted. Older batteries that no longer hold a charge can cause the internal clock to lose time, especially if the phone powered down completely. Plugging in and restarting usually fixes this within a minute or two.

If you've recently crossed time zones and your phone didn't update automatically, check that Location Services is turned on. Your phone uses location data to figure out which time zone you're in. On iPhone, go to Settings > Privacy > Location Services; on Android, check Settings > Location.

Changing the time zone without changing the clock time

Sometimes you need to adjust your time zone but keep the actual clock time the same — for example, if you're traveling but want your calendar and alarms to stay on your home schedule. On iPhone, you can change the time zone by going to Settings > General > Date & Time and adjusting the time zone field while leaving "Set Automatically" on. This updates which zone your phone thinks it's in without changing what the clock displays.

On Android, the process is similar: go to Settings > System > Date & Time, turn off "Automatic Date & Time," and then adjust only the time zone field while leaving the clock time alone. Be aware that some apps — especially calendar and email — may recalculate their times based on the new zone, so check those after you make the change.

What to do if your phone won't hold the time you set

If you change the time and it reverts within minutes or hours, your phone is likely re-syncing with an automatic time source. First, make sure "Set Automatically" (iPhone) or "Automatic Date & Time" (Android) is actually turned off — toggle it off, wait a few seconds, and toggle it back on to reset the connection. Then turn it off again and set your time manually.

If the time still won't stick, restart your phone completely. Power it all the way down, wait 10 seconds, and turn it back on. Then go back to the date and time settings and make your change. If it still reverts, your phone may be having trouble with its internal clock hardware, and you may need to contact the manufacturer or a repair service.

On rare occasions, a software update can reset your date and time settings. After any major update, check your clock to make sure it's still correct and that automatic updates are set the way you want them.

Using 12-hour versus 24-hour time format

Changing between 12-hour (with AM/PM) and 24-hour format is separate from changing the actual time. On iPhone, go to Settings > General > Date & Time and scroll down to find "24-Hour Time." Toggle it on or off depending on your preference. On Android, the option is usually in Settings > System > Date & Time under "Time Format" or "Use 24-hour Format."

This setting affects how the time displays on your lock screen, in notifications, and in most apps, but it does not change what time your phone actually thinks it is. If you switch formats and your clock suddenly looks wrong, you've only changed how it's displayed, not the time itself.

Syncing time across multiple devices

If you have an iPhone and an Apple Watch, or an Android phone and a Wear OS watch, the watch usually syncs its time automatically from the phone. If your watch shows a different time than your phone, restart the watch first. If that doesn't work, go into the companion app on your phone (Watch app for iPhone, Wear OS app for Android) and look for a time sync or restart option.

For other devices like tablets or computers, each one pulls time from the internet independently, so they should all match if they're connected to Wi-Fi or cellular. If one device is consistently off, check its individual date and time settings rather than trying to sync them manually.

Frequently Asked Questions

Can I set a custom time that's not the actual current time?

Yes, but only if you turn off automatic time updates first. Once automatic is off, you can set any time you want. Be aware that this will affect alarms, reminders, and any app that relies on the correct time, so most people only do this temporarily for testing or troubleshooting.

Why does my phone change the time when I cross time zones?

If "Set Automatically" or "Automatic Date & Time" is on, your phone detects your location through GPS, cellular data, or Wi-Fi and adjusts the time zone automatically. This keeps your clock accurate without you having to do anything. You can turn this off if you want to stay on one time zone while traveling.

Does changing the time on my phone affect my alarm or calendar?

Yes. If you change the time backward, an alarm set for later today may go off immediately or not at all. Calendar events will display at the new time relative to your clock. For this reason, only change the time when necessary, and check your alarms and calendar afterward to make sure they're still set correctly.

What if my phone shows the right time but the wrong time zone?

Go to your date and time settings and look for a separate time zone field. Adjust that without touching the clock time itself. This is useful if you're traveling but want to keep your phone on your home time zone, or if your phone guessed wrong about where you are.