How to unpair and erase your Apple Watch for sale
These are the steps you need to take when you need to sell or give away an Apple Watch you’ve been using. You must take these steps to disconnect your watch from your iCloud account and erase personal data, including Apple Pay (if you have enabled it).
It’s essential you unpair your device in order that the next person to use the Apple Watch can fully configure it for their needs.
Keep your Apple Watch and paired iPhone close together during all these steps.
Where’s the serial number?
It will be useful to find the serial number for your Apple Watch. On a Series one watch, you’ll find this on the back of the device, while on a Series Two you’ll find the serial number written very small on the space revealed when you remove the strap from its connection near the Digital Crown.
Alternatively, you’ll find the number in Settings>General>About on your watch or in the Apple Watch app (MyWatch>General>About) on your iPhone. You may need this serial number for some of the following steps.
To unpair the Apple Watch you open the Apple Watch app on your iPhone, tap My Watch>Apple Watch>Unpair Apple Watch. Now you should choose the watch you want to unpair and tap Unpair. This process usually takes a few minutes to complete, as unpairing also deletes content.
Hint: If you use multiple Apple Watches and find that you need to unpair them you’ll probably need to use the serial number to identify the correct watch. To make this a little easier you can give each watch a name, which makes them much easier to recognize in future. To do so open the Apple Watch app on your iPhone, tap on My Watch, choose the appropriate watch, tap General>About>Name, delete the current name and give it a new one.
Remove Payment Cards
If you lose or sell a Watch that’s equipped with Apple Pay you will need to remove the payment details from your old watch.
Sign-in to your Apple ID at iCloud.com.
Open Settings>My Devices
Select the device you want to remove and click the X by its name in the list.
Unpair Apple Watch without an iPhone
To erase all the content on your watch you should:
Open Settings on the Home screen.
Go to General>Reset and tap the Erase All Content and Settings option. This will reset your Apple Watch to factory settings.