How to set up iPhone Handoff on iOS 27, step by step

What you need: two iPhones running iOS 27 or later, both signed into the same Apple Account, Wi-Fi on both devices, and an eSIM from a carrier that actually supports the feature. Time: about 5 to 10 minutes if everything above is already true, longer if you need to update software or wait for your carrier to provision the eSIM.

What iPhone Handoff actually does

Confusingly, Apple has reused a name it already had. The name is separate from Apple’s older Handoff feature for continuing activities across devices. That older feature, the one that lets you pick up a Safari tab on your Mac after starting it on your iPhone, still exists and still works the same way it always has.

The new iPhone Handoff, added in iOS 27, operates at the cellular level. iOS 27 introduces iPhone Handoff, an eSIM feature that lets the same phone number work across two iPhones and automatically switches cellular service between them. Only one iPhone is active on the network at a time, and unlocking the other device moves the number to it. Calls, voicemail, iMessage, RCS, SMS and MMS messages, and Find My location follow the active iPhone.

It’s aimed at anyone juggling two iPhones on purpose, a work phone and a personal one, a big Pro Max for the desk and a smaller phone for a run, or now, a foldable and a backup. Verizon’s own framing is explicit about this: the feature lets you switch between the pocketable iPhone Duo on the go or iPhone 18 Pro for work while keeping the same number active.

What you need before you start

Apple’s requirements are stricter than a normal eSIM transfer. Apple’s iPhone Handoff documentation says both devices must run iOS 27 or later, share the same Apple Account, use Messages in iCloud, and be signed into FaceTime and iMessage with the same account. Both devices also need Wi-Fi access during setup and an eSIM from a participating carrier.

That last part matters more than it sounds. This isn’t a feature you can just turn on if your phones meet the software requirements. Your carrier has to have switched it on for your account, and a physical SIM card is not sufficient, you need an eSIM specifically.

Before you touch either phone, check both are updated to iOS 27 or later (Settings > General > Software Update), confirm both are signed into the same Apple Account (Settings > [your name]), and turn on Messages in iCloud (Settings > Messages > Messages in iCloud). Then check with your carrier that Handoff is live on your plan, because several carriers are still rolling it out.

How to set up iPhone Handoff on two iPhones you already own

If both iPhones are already set up and in daily use, here’s the path, verified against Apple’s own support documentation as cited by MacRumors:

On the iPhone you want to add, open Settings, then tap Cellular. (If both iPhones are already set up, open Settings ➝ Cellular on the phone you want to add.)
Tap Set Up Cellular or Add eSIM. Tap “Set Up Cellular” or “Add eSIM.” If a number is already active on that device, the menu instead reads “iPhone Handoff.”
Choose Use Number on This iPhone and Another, then tap Continue. Tap Set Up Cellular or Add eSIM, choose Use Number on This iPhone and Another, and follow the prompts.
Follow the on-screen prompts on both phones. You then get to choose which device is your main iPhone (ideally, the one you use most often) and which is your secondary iPhone.
Once both devices confirm setup, unlock the second iPhone. Once both devices confirm setup, unlock the second iPhone. You should see the “Switched to this iPhone” message or the Dynamic Island indicator appear after the switch.
Place a test call before you rely on the secondary phone for anything important. Place a test call from that phone before relying on it for anything important; the confirmation message tells you setup finished, but an actual call is a better check that the carrier side is working.

Setting it up while activating a new iPhone

If you’re setting up a brand new iPhone, Handoff can be configured during the initial activation screens instead. During activation, when you reach the “Set Up Cellular” screen, select “Use Number on This iPhone and Another.” Follow the prompts on the new iPhone, then switch to your existing iPhone to complete the matching prompts when they appear there too.

In this flow the new iPhone becomes the main device by default, and your old phone becomes the secondary one, though you can confirm or change that during setup. Keep both phones next to each other and on the same Wi-Fi network while you do this; the prompts bounce back and forth between the two screens and it’s easy to miss one if the phones are in different rooms.

Once it’s working: switching between the two phones

After setup, switching is passive. The feature assigns a phone number to two iPhones, but only one is active at a time. Lock the phone you’re moving away from and unlock the one you want to use instead; the network side follows automatically. Some carrier settings remain tied to the main iPhone, including Caller ID, Call Forwarding, and carrier account management, so if you need to change those, you’ll need the main device in hand.

Third-party apps carry over too, with one caveat. Third-party apps work on both phones; however, some sensitive apps, such as banking apps, may require you to sign in again or grant access from your other device as a security precaution. That’s expected behaviour, not a bug.

What it costs, by carrier

This is the part that’s drawn the most attention. Apple built the feature, but carriers get to decide whether it’s free or a recurring charge, and so far the prices vary a lot.

Carrier	Country	Monthly price	Status
T-Mobile	US	$5	Available now
Verizon	US	$10	Coming soon, no launch date given
AT&T	US	Not supported	Noncommittal on the feature
EE	UK	Free on Full Works Plus, otherwise £5	Coming soon
Deutsche Telekom	Germany	€6.95, free on top two MagentaMobil plans	Live, only German carrier supporting it so far

iPhone Handoff will be available from Verizon for $10/month on compatible iPhones models running iOS 27. T-Mobile says iPhone Handoff costs $5 per month and works with compatible iPhones running iOS 27. T-Mobile and Deutsche Telekom are the first carriers to offer iPhone Handoff, and Apple said Verizon and EE will add support later this year, but AT&T is noncommittal about the feature.

In the UK, iPhone Handoff will be available for free as part of its Full Works Plus plan, and available for £5/month on its other plans… iPhone Handoff is coming soon. In Germany, the function runs via Telekom’s MultiSIM, which costs €6.95 per month without a suitable tariff, though Germany’s Deutsche Telekom charges €6.95 a month but includes it free on its two highest MagentaMobil plans. Austria and Switzerland don’t have it yet at all, since it is not currently available in Austria or Switzerland.

Common problems and how to fix them

Because this touches both software and carrier provisioning, most issues trace back to one side or the other not being ready. Work through these before assuming something is broken.

Problem	Likely cause	Fix
“Use Number on This iPhone and Another” option never appears	One phone isn’t on iOS 27, or isn’t signed into the same Apple Account	Update both phones in Settings > General > Software Update, confirm the Apple Account matches on both
Cellular menu only shows “Add eSIM,” no Handoff wording	Your carrier hasn’t turned the feature on for your account yet, or doesn’t support it (like AT&T currently)	Check with your carrier directly; confirm you’re on a plan and SIM type they list as eligible
Setup completes but the second iPhone never gets signal	Wi-Fi dropped on one device mid-setup, or the carrier eSIM is still provisioning	Reconnect both phones to Wi-Fi, wait a few minutes, then restart the secondary iPhone
No “Switched to this iPhone” message or Dynamic Island indicator after unlocking	The switch didn’t register properly	Lock and unlock the phone again, then place a test call to confirm which device actually has service
Banking or payment app asks you to log in again on the new device	Expected security behaviour, not a fault	Just sign back in; it’s by design for sensitive apps
Unexpected line item on your bill	Monthly Handoff fee (Verizon $10, EE £5, Deutsche Telekom €6.95 unless on a qualifying plan)	Check whether your plan includes it free (EE Full Works Plus, Deutsche Telekom’s top two MagentaMobil tiers) or whether it’s worth cancelling if you rarely switch

What this means for you

If you already own two iPhones and your carrier supports Handoff, setup takes a few minutes and the menu path is straightforward: Settings, Cellular, Set Up Cellular or Add eSIM, then Use Number on This iPhone and Another. The harder part is checking your carrier actually offers it and deciding whether the monthly fee is worth it.

On a US plan, that’s the difference between T-Mobile’s $5 and Verizon’s $10 for the identical function. In the UK, EE customers already on Full Works Plus get it free; everyone else pays £5. In Germany, it only runs on Deutsche Telekom for now, and the fee disappears if you’re on one of its top two plans. If you only occasionally hand your number between two phones, weigh that monthly charge against how often you’d actually use it before switching it on.