How do I activate cellular service on Apple Watch Series 5 or Apple Watch Series 4? How does it work?

Good news—your iPhone and Apple Watch Series 5 or Apple Watch Series 4 will share the same phone number. So you won’t have to get or remember another phone number. Apple Watch Series 5 or Apple Watch Series 4 has an embedded SIM (eSIM) in it, so there’s no need to get a SIM card or transfer the SIM from another device. When you pair your Apple Watch to your iPhone, you will be prompted to set up cellular service and guided through a few simple steps. If you don't see a plan during setup, contact us and we can help you find one that works for you. If you choose not to set up cellular service during the initial Apple Watch setup process, you can always go back later to the Apple Watch app on your iPhone and select Cellular under My Watch to sign up.