Based on official announcements from Shanghai Telecom, Nanjing Telecom, and other branches, China Telecom has reinstated its nationwide "One Number, Two Terminals" eSIM service for Apple Watch on November 4, 2025. The resumption of eSIM services for watches from other brands remains pending further updates. The "One Number, Two Terminals" service enables users to add an Apple Watch as an eSIM secondary device (secondary SIM) under their existing mobile phone number (primary number) account and plan. This allows both the phone and the watch to share the same number, as well as the voice calls and data included in the plan. Users can make calls and access the internet independently on each device. To qualify for this service, the following requirements must be met: the watch must run on watchOS 10.3 or later, the iPhone must be updated to iOS 26.1 or later, and the watch model must be an Apple Watch Series 7 (A2476/A2478) or a newer model that supports eSIM functionality. Users who signed up for the service on or after June 1, 2021, are required to pay a monthly fee of 10 yuan for the service. For users with primary and secondary SIM plans, the voice and data allowances specified in the plan are shared between the devices, with additional charges applying for any usage beyond the plan limits. For users without such a plan, the "One Number, Two Terminals" secondary device comes with 500MB of data and 60 minutes of voice calls, with separate charges for any usage exceeding these limits.