Apple requires you to create a PIN during the initial Apple Watch setup process. You are then asked to enter the code to unlock the watch each time you take it off your wrist. But what happens if you ever forget the code? There's no need to worry, it can be reset in a few short steps. Here's what you need to know:
Reset it from an iPhone
To reset the watch from a paired, click the app on the phone's home screen and select General. Then, scroll down to the bottom of the page, tap Reset and choose Erase All Content and Settings.
This will return the watch to its original out-of-box state, unfortunately that means everything on it will also be deleted. The good news is that your iPhone automatically creates a backup of the watch when it's unpaired using this method. When you're ready to re-pair it, simply select the restore from backup option during the setup process.
Reset it on the watch
You can still reset the watch even if your iPhone isn't with you, but you will need the watch's magnetic charging cable close by. To start, hold and press the side power button on the watch. Then perform a Force Touch, which is a hard press, on the Power Off option and select Erase All Content and Settings. At this time you must connect the watch to the charger, and then confirm that you want to reset it.
Prevent this from happening
I try to use a passcode that I won't forget, such as a date for an anniversary or birthday. It would also help to make a note of the code on your iPhone or in another secure location. But really the easiest way to ensure that you aren't locked out of the Apple Watch is to enable the Unlock with iPhone feature. This will let you unlock the Apple Watch with your iPhone, instead of entering the PIN.
To enable this feature, open the Apple Watch app on your iPhone, select Passcode and toggle the Unlock with iPhone switch from off to on. It can also be enabled directly on the Apple Watch by going to Settings, tapping Privacy and sliding the switch from off to on.