If your Apple Watch locks unexpectedly
Make sure Apple Watch can detect that it’s on your wrist to avoid unexpected locking and other issues.
Apple Watch uses a sensor to detect when you’re wearing it. If you set a passcode on your watch, the watch locks automatically when you take it off to keep your information secure.
If Apple Watch can’t detect that it’s on your wrist
You might notice these issues:
Apple Watch locks unexpectedly and requests the passcode while you’re wearing it.
Apple Watch doesn’t display notifications.
The Workout app pauses unexpectedly while you’re exercising.
Apple Watch doesn’t provide reminders to stand.
Apple Watch doesn’t record your heart rate automatically.
Identify factors affecting wrist detection
Wearing your Apple Watch too loosely or too tightly. Your watch should lie flat on the top of your wrist so that the sensor on the back of the watch makes contact with your skin.
Something between Apple Watch and your wrist, like a bracelet or shirt sleeve.
Permanent or temporary changes to skin, like scars or tattoos. The ink, pattern and saturation of some tattoos can block light from the sensor, making it difficult for your watch to detect when it's on your wrist.
Make sure your Apple Watch can detect your wrist
Adjust your Apple Watch band so that your watch stays in contact with your skin. The fit should be snug but comfortable.
Make sure nothing is between your Apple Watch and your wrist.
If you have a scar or tattoo on the wrist where you wear your Apple Watch, try switching to your other wrist. Make sure to update your watch’s orientation: open the Settings app on your watch, tap General, tap Orientation, then choose Left or Right.
Turn off wrist detection
If you think wrist detection is still causing issues, you can try turning it off:
Open Settings on your Apple Watch.
Tap Passcode.
Tap Wrist Detection to turn the feature off.
Enter your passcode.
Tap Turn Off to confirm.
Note the features that become unavailable
When you turn off wrist detection, a screen appears with these important notes:
Your Apple Watch will not lock or unlock automatically.
Fall Detection will not automatically start Emergency SOS.
Heart rate tracking and notifications will be turned off.
Blood Oxygen background measurements will be turned off.
Respiratory rate background measurements will be turned off.
Sleep tracking will be unavailable.
Some Activity measurements will be unavailable.
Noise measurements and notifications will be turned off.
Tap gestures and wrist flick will be turned off.
Additionally, when you use Apple Pay on your Apple Watch, you’ll be prompted to enter your passcode when you double-click the side button to authorise the payment.