Apple Watch won't unlock your Mac: check Bluetooth, Wi-Fi and the watch switch

Why it happens

Your Mac and watch use Bluetooth and Wi-Fi together to check that the watch is right next to the Mac. If either is off on the Mac, the watch can't do it, even when the switch is on. The watch also needs a passcode and must be on your wrist and unlocked, and your Apple Account needs two-factor authentication.

How to fix it

1. Open Control Center in the menu bar and check that Wi-Fi and Bluetooth are both on. If Bluetooth is off, turn it on in Bluetooth settings.

   Bluetooth

2. Check Wi-Fi in System Settings too. The switch must be on, though the Mac doesn't need to be connected to a network.

   Wi-Fi

3. Click Touch ID & Password in the sidebar. Under Apple Watch, turn on the switch next to your watch's name and type your Mac password if asked. On a Mac without Touch ID, the page is called Login Password instead.

   Touch ID & Password

4. Put the watch on, unlock it with its passcode, then lock the Mac with Control-Command-Q. Wake it with the watch close by: it should tap your wrist and open your Mac.

Still not fixed?

1. Turn off Internet Sharing on the Mac. While it's on, the watch can't sign you in.

   General›Sharing›Internet Sharing

2. On your iPhone, open the Watch app and check that the watch has a passcode and Wrist Detection is on. Without them, the watch can't stay unlocked on your wrist.

3. Make sure the Mac and the iPhone paired with your watch use the same Apple Account, with two-factor authentication on.

4. After a restart, your Mac always wants the password once. Type it, and the watch works again after that.

5. Turn the watch switch off, restart both the Mac and the watch, then turn it on again. Also turn Bluetooth off and on in Bluetooth settings.

   Bluetooth

6. If Bluetooth won't turn on, or your watch never appears under Apple Watch, contact Apple Support. Bluetooth that won't switch on can be a hardware fault.