Unfortunately, not. Your iPhone and Apple Watch must use the same carrier. If you change carriers on your iPhone, you need to remove the previous service plan on your Apple Watch and sign up for a new plan. With Virgin Mobile, enjoy a 6-month free cellular subscription and go without your iPhone. All you need is an active data plan of your choice. Keep in mind; you will need to buy roaming data separately to be able to use your Apple Watch abroad.
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