Apple's iOS 27 introduces iPhone Handoff, an eSIM feature that lets you use the same phone number on two iPhones and switch the active device by unlocking it. The number remains active on only one iPhone at a time, so the feature does not create two independently usable lines.

iPhone Handoff is separate from Apple's existing Handoff feature, which lets users continue app activities across Apple devices. Instead, the new cellular feature moves core phone services, including calls, voicemail, messages and Find My location, to whichever iPhone is active.

What iPhone Handoff transfers

When the number switches, calls, voicemail and messages move to the newly active iPhone. That includes iMessage, RCS, SMS and MMS. A message reading “Switched to this iPhone” confirms the change.

Other information stored in iCloud continues syncing between the two devices. Third-party apps remain available on both iPhones, although some may require another sign-in or take time to synchronize. Banking apps can also ask users to approve access on the second device.

Apple Watch pairing does not move automatically with the phone number. Users should pair the watch with the iPhone they expect to use most often. Some Wallet items, including certain transit passes and IDs, may also work on only one device at a time. Carrier account management, Call Forwarding and Caller ID remain associated with the main iPhone.

Compatible iPhones and carrier support

Both iPhones must run iOS 27 or later, connect to Wi-Fi and use the same Apple Account. Messages in iCloud must be enabled, and both devices must use the same Apple Account for FaceTime and iMessage.

Dual SIM is supported when both eSIMs come from carriers that offer iPhone Handoff. Each eSIM must be enrolled separately, but the paired eSIMs switch together when either iPhone is unlocked.

In the United States, T-Mobile currently supports the feature. Telekom supports it in Germany. Verizon in the US and EE in the UK are expected to add support later in 2026. AT&T has not committed to supporting iPhone Handoff and has instead pointed to its existing eSIM activation and transfer options.

How much does iPhone Handoff cost?

T-Mobile charges $5 per month for iPhone Handoff. Deutsche Telekom charges €6.95 per month in Germany on plans that do not already include multi-SIM service. The carrier includes one multi-SIM connection with its current MagentaMobil L plan and two with the XL plan. Other carriers have not announced pricing.

How to set up or remove the feature

During new iPhone setup, select Use Number on This iPhone and Another at the Set Up Cellular screen, then follow the instructions on both phones. On already configured devices, open Settings, choose Cellular, select Set Up Cellular or Add eSIM, and choose the same option. Setup then asks users to identify a main and secondary iPhone.

To replace one of the paired phones, add the eSIM on the replacement iPhone through Cellular settings, select the existing iPhone and choose Transfer. The eSIM on the transferred-from iPhone will deactivate. If the carrier does not support that transfer route, iPhone Handoff must be enrolled again.

Stopping the service requires contacting the carrier. Deleting an eSIM alone may not end the carrier's charges.