T-Mobile will add a $5 monthly fee for iPhone Handoff, Apple’s new iOS 27 feature that lets customers share one phone number across two iPhones.
The carrier confirmed the pricing alongside its iPhone 18 Pro announcement, making it the first U.S. carrier to support the feature at launch.
iPhone Handoff works through eSIM technology. When enabled, one iPhone acts as the primary device and the other serves as a secondary that shares the same number.
Switching between them happens automatically when you unlock either device, and only one iPhone can have the number active at a time.
Calls, texts, data, mobile hotspot, Scam Shield, and T-Satellite all function on both devices under an eligible T-Mobile plan.
What it takes to use it
Both iPhones need to run iOS 27, be connected to Wi-Fi, and be signed into the same Apple Account with FaceTime, iMessage, and Messages in iCloud turned on. Setup happens either during new iPhone activation or through the Settings app.
Outside the U.S., Deutsche Telekom customers in Germany are the only other carrier subscribers who can use it at launch.
A few limitations are worth knowing before signing up. Payment cards and car keys in the Wallet app carry over to both iPhones, but Apple cautions that some Wallet items, including transit passes, government IDs, and corporate badges, may only function on one device at a time.
iPhone Handoff does not transfer an Apple Watch pairing from one iPhone to the other, so users who switch between devices will need to stay on their primary iPhone for watch functionality.
Dual SIM support and setup details
The feature is compatible with Dual SIM configurations, provided both eSIMs are from carriers that support iPhone Handoff.
In that case, both eSIMs switch simultaneously when you unlock an iPhone, though each eSIM must be configured individually.
Once activated, iPhone Handoff stays on until a customer contacts their carrier directly to disable it. Apple has published a support document with full setup instructions.
To try iPhone Handoff, you’ll need a pair of compatible iPhones on iOS 27 and T-Mobile’s $5 monthly add-on.
