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Sync an Apple Watch (GPS + Cellular) to a new iPhone with NumberSync

Want to sync your watch to a different iPhone? Learn how to sync your Apple Watch Series 3 or Series 4 (GPS + Cellular).

Use NumberSync on a different iPhone

You can sync an Apple Watch Series 3 or Series 4 (GPS+ Cellular) to:
  • A different iPhone® with a different wireless number on your account.
  • A different iPhone on a different billing account than your Apple Watch. Make sure you have the user ID and password for that account.
  • A new iPhone that you upgraded to and that has your current mobile number.

Already synced your Apple Watch Series 3 or Series 4 (GPS + Cellular) to an iPhone? First, un-sync the watch from that device. Then, use NumberSyncSM1 to connect it to a new iPhone.

Unsync your watch from your current iPhone
  1. Select the Watch app.
  2. Once you see the My watch screen, press the picture of the watch to remove.
  3. Select the information icon.
  4. Select Unpair Apple Watch.
  5. Select Keep Plan.

Wait for the process to complete before you sync your new iPhone.

Sync your new iPhone

If you’ve upgraded to a new iPhone, make sure to complete the activation process before syncing it to your Apple Watch Series 3 or Series 4.
  1. Go to the Watch app on your iPhone and follow the prompts to start pairing.
  2. Select Set up Cellular. Syncing to another iPhone with a different mobile number? Select OK when you see a message asking if you want to sync with another phone. (If you upgraded to a new iPhone you won’t see this message.)
  3. Enter the Emergency 911 address. This is the address where you’ll use the watch most often. 
  4. Make sure to check the box and read the Important Information for NumberSync on the 911 screen. 
  5. Select Ok on the Sync requested screen when you see a message that NumberSync should be available shortly. 
  6. Follow the prompts to finish setting up your watch.

Good to know: When you place a 911 call using your watch, the call goes over the mobile network when possible. If a mobile network isn’t available, emergency services use device location data from nearby Wi-Fi networks to locate you. If that data isn’t available, they’ll come to the address you provide.

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Last updated: December 7, 2022

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