Unlock with Apple Watch not working on iPhone? Fixes that follow Apple's rules

You are wearing a mask, you raise your iPhone, and it still asks for a passcode. Your watch is right there. This feature has rules that most guides skip, and one of them explains a lot of cases: it was built for times when Face ID cannot see your face. This guide starts with that rule, gives Apple's checklist, and then walks through the fixes in order.

What is Unlock with Apple Watch actually for?

Apple's Watch guide says the feature lets your watch unlock your iPhone for Siri requests, or when something stops Face ID from recognizing your face. Apple's support page says you need to wear a mask that covers your mouth and nose, or sunglasses or ski goggles that cover your eyes. If nothing blocks your face, Face ID does the work and the watch is not used. So if you try it with a bare face and it does nothing, that can be normal.

It also does not use Face ID to check who you are. Apple says it works only for unlocking your iPhone, and it doesn't verify your identity for Apple Pay, passwords stored in Keychain, or password-protected apps. For those, you still enter your passcode.

Apple's requirements, as a checklist

The hidden conditions in Apple's security guide

Apple's Platform Security guide lists more conditions. Based on an excerpt of that page, the iPhone must have been unlocked by another method at least once after the watch was put on your wrist and unlocked, and within the past 6.5 hours. The sensors must detect that your nose and mouth are covered. The iPhone and watch must be within about 2 to 3 meters. The watch can't be in bedtime mode. Check the guide yourself if the exact numbers matter to you.

In practice this means a phone that has just restarted may refuse to use the watch until you unlock it once the normal way, with your passcode. That surprises many people, but it is a safety rule, not a fault.

How to turn it on

How to use it

Unlock with Apple Watch not working: fixes in order

Steps 4 to 7 are common fixes, not instructions on Apple's page, which has no troubleshooting section. If the watch will not connect at all, read our guide to an Apple Watch that won't connect. If it needs an update first, see what to do when an Apple Watch won't update, and check which Apple Watches work with watchOS 27.

How to check wrist detection and the watch passcode

Two of Apple's requirements live on the watch side, and people often forget them. Apple says the watch needs a passcode, and wrist detection must be on. On most versions you can check both in the Watch app on your iPhone. Open the Watch app, tap My Watch, then tap Passcode, and look for Wrist Detection. Menu names can differ by version, so use the search bar in the Watch app if you cannot find it. If wrist detection is off, Apple says you will be asked to turn it on when you enable the unlock setting.

Also check the watch itself. If it is on a charger, off your wrist, or showing the passcode screen, the iPhone cannot use it. Apple says the watch must be on your wrist and unlocked. A loose band can make the watch lose its wrist detection, so wear it snug enough that the sensor stays against your skin.

Why does my iPhone ask for the passcode after the watch unlocked it?

If you did not mean to unlock the phone, you can tap the Lock iPhone button on the watch screen. Apple says the next time you unlock your iPhone after tapping that button, it requires your passcode. If you tapped it by accident, that is why you are being asked. Use your passcode once and the watch can work again.

Face ID with a mask on iPhone 12 and later

On iPhone 12 and later with iOS 15.4 or later, Apple says Face ID can work while you wear a mask, without an Apple Watch. Apple says you can combine it with Unlock with Apple Watch. If you wear the mask too high or too close to your eyes, Face ID may fail, and Apple says it does not work in landscape mode with a mask. So if your iPhone is new, Face ID may do the job and the watch becomes a backup. If your Face ID has trouble, see our page on Face ID not working.

What about iPhone Duo?

Apple's wake and unlock guide says that iPhone Duo uses Touch ID in the side button, and that you can also use your Apple Watch to unlock your iPhone Duo. If you own one, the same watch requirements apply. For more on the phone, see what Apple has confirmed about the iPhone Duo.

Common mistakes

• Testing it without a mask. Face ID handles that case, so the watch is not needed.
• Forgetting wrist detection. Apple says it must be on.
• Skipping the first passcode unlock. After a restart, unlock with your passcode first.
• Forgetting to unlock the watch. The watch must be on your wrist and unlocked.
• Expecting it to approve payments. It does not work for Apple Pay.

Which devices does this cover?

The feature needs an iPhone with Face ID (iPhone X or later) and an Apple Watch Series 3 or later, with the software versions in the table above. Apple's pages name iOS 14.5 and watchOS 7.4 as the minimums, and your devices will normally be far past that. Menu names can change between versions, so use the search bar in Settings for Face ID & Passcode if you cannot find it.

When to contact Apple

If you have checked every requirement, updated both devices and paired the watch again, and it still will not work, contact Apple Support. Tell them your iPhone and watch models and versions, and say whether Face ID works on its own.

The short version

Wear a mask or sunglasses, keep the watch unlocked on your wrist and close, check wrist detection and the passcode, and unlock the iPhone once by passcode after a restart. Then turn the setting off and on.