iOS 27 can put one phone number on two iPhones at once. Pick up either handset, unlock it, and your calls and texts follow you. It is one of the better ideas in the update, and in the United States you can only get it from one carrier, which wants $5 a month for it.
AT&T, meanwhile, has told CNET it sees “potential” in the idea and then pointed at the eSIM transfer tools it already has. If you are on AT&T, that reads as a no for now.
What iPhone Handoff Does
The name is confusing, because Apple already has a feature called Handoff that passes an open email or a Safari tab from your iPhone to your Mac. iPhone Handoff is a different thing. It is a carrier feature built on eSIM, and it lets two iPhones share a single number.
Only one phone holds the number at any moment. When you unlock the other one, your calls, voicemail, iMessage, RCS, SMS and MMS move across, along with your Find My location, and the screen shows “Switched to this iPhone” to confirm it. Everything you keep in iCloud stays in sync on both phones anyway, and third-party apps run on either, although some will make you sign in again and banking apps may ask you to approve the second device.
The obvious buyer is anyone who took the plunge on the iPhone Duo and does not want to carry a $1,999 folding phone to the gym, the beach or a five-year-old’s birthday party. Keep an older iPhone as the knockabout phone, unlock whichever one you grabbed, and nobody ringing you notices the difference. T-Mobile is pitching it at exactly that crowd: its statement says the feature is “ready to use from day one on the new iPhone 18 Pro lineup and iPhone Duo.”
Which Carriers Support It, and What It Costs
| Carrier | Status | Price |
|---|---|---|
| T-Mobile (US) | Live now | $5 a month |
| Telekom (Germany) | Live now | €6.95 a month, unless your plan already includes multi-SIM |
| Verizon (US) | Coming later this year | Not announced |
| EE (UK) | Coming later this year | Not announced |
| AT&T (US) | No commitment | n/a |
The German pricing has a wrinkle worth knowing if you are on Telekom. MagentaMobil L already includes one multi-SIM and XL includes two, and Telekom only charges the €6.95 on plans that lack one.
Verizon and EE customers will have to wait for Apple’s “later this year”, with no price attached yet. No other UK network has said anything.
What AT&T Said
The full quote from the AT&T spokesperson: “While we see that there could be potential in capabilities like iPhone Handoff, our focus remains on delivering innovations that make life simpler and keep customers connected with confidence.” The statement then pointed to “existing eSIM activation and transfer options across compatible devices.”
Those transfer options exist, and they solve a different problem. Moving an eSIM from one iPhone to another is a setup job you do once when you upgrade. iPhone Handoff switches the number every time you pick up the other phone, with no menus involved. Offering one in place of the other misses what people want from the feature.
AT&T has not ruled it out, so this could change. With T-Mobile live and Verizon on the way, AT&T will be the only one of the big three without it by Christmas.
What You Need to Use It
Both phones need iOS 27 or later, which covers anything on Apple’s supported list back to the iPhone 11. On top of that, both phones must be:
- Connected to Wi-Fi
- Signed in to the same Apple Account
- Using Messages in iCloud
- Signed in to FaceTime and iMessage with that same account
It works alongside Dual SIM, as long as both eSIMs come from carriers that support it. You set each one up separately, and after that both switch together when you unlock the phone.
Setup lives in Settings, then Cellular. Tap Set Up Cellular or Add eSIM, choose Use Number on This iPhone and Another, and follow the prompts on both phones. You also pick which one is your main iPhone. Choose the one you use most, because a few things stay tied to it. On a brand new iPhone the same option appears on the Set Up Cellular screen during setup.
The Catches
Know these four things before you switch it on:
- Your Apple Watch stays paired to one iPhone. It does not follow the number.
- Some Wallet items, including certain transit passes and IDs, only work on one device at a time.
- Call Forwarding, Caller ID and carrier account management remain tied to the main iPhone.
- To stop paying, you have to contact your carrier. Deleting the eSIM from the phone may not stop the charge.
That last one is worth writing down. Removing a line from Settings feels like cancelling it, and on T-Mobile it may leave you paying $5 a month for a feature you no longer use.
If you replace one of the two phones, you transfer the eSIM to the new handset while it sits next to the others. The old phone loses the eSIM when the transfer completes.
Is $5 a Month Worth It?
For the right person, yes. $60 a year is a fraction of what a second line costs on any major US carrier, and a second line would give you a second number, which is the opposite of what most people want here.
It is harder to justify if you only switch phones now and then. An occasional swap is already possible with the eSIM transfer tools AT&T keeps pointing at, and those cost nothing. The monthly fee earns its keep when you switch every day, which is what a Duo owner with a spare phone will do.
The charge itself bothers me. Apple wrote the software that does the switching, and T-Mobile is billing you for access to it. Telekom bundling it into the bigger plans looks like the fairer model. Verizon and EE have yet to pick one. If you want a cheap hedge for the days your carrier falls over, as T-Mobile did in July, a spare data eSIM is still the better buy.
Will You Pay for It?
Are you using iPhone Handoff on T-Mobile yet, and does the $5 feel fair? And if you are on AT&T, is this enough to make you think about moving? Tell us in the comments.
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