How to transfer data from another iPhone to iPhone Duo

You can move your old iPhone's data to iPhone Duo in three Apple-supported ways: Quick Start, which copies everything straight from phone to phone, a restore from an iCloud backup, or a restore from a computer backup. This guide focuses on Quick Start and iCloud. Both happen during setup, and both leave a few things behind that you'll need to redo by hand, starting with your fingerprints.

This guide covers the data move only. For the rest of the first-run screens, see the guide to setting up a new iPhone Duo, and for your phone number, see how to move your eSIM.

Before you start

Apple's Quick Start support document says the old phone needs iOS 11, iPadOS 13 or later, and it recommends updating both devices to the latest version of iOS before you begin. Quick Start ties up both phones, so Apple suggests picking a time when you won't need the old one for several minutes.

Plan to keep both phones close together and plugged in until the transfer finishes, which is Apple's own instruction.

Expect a software update somewhere in setup. MacRumors reported that iPhone Duo ships with iOS 27.1 and that users need to install a newer iOS 27.1 build, while Apple's spec page lists the phone in the box only as coming with "iOS 27." An earlier MacRumors report said the update is required during iPhone Duo setup, but neither Apple nor MacRumors says exactly where in setup it appears. That same report cautioned that Apple could release another build before launch, so the version offered on your screen may be newer than the one MacRumors named.

One hardware note: iPhone Duo doesn't take physical SIM cards. Apple's iPhone Duo spec page lists dual eSIM and says the phone won't work with a physical SIM, so if your old iPhone uses one, read the eSIM guide before you start.

Quick Start or iCloud backup: which should you use?

Use Quick Start if your old iPhone is working and in front of you. If you pick the direct-transfer option, Quick Start copies from the old phone itself, so it doesn't depend on your iCloud storage or on when your last backup ran.

Quick Start itself gives you two choices once the phones are paired. According to Apple, if you choose to download from iCloud, you can use the new phone right away while apps and data download in the background; if you transfer directly from your previous device, you wait for the transfer to finish on both phones.

Quick Start can also run over a cable. Apple's wired transfer document says moving from an iPhone 15 or later to an iPhone 15 or later uses a USB-C Charge Cable between the two charging ports, while an iPhone 14 or earlier needs a USB-C to Lightning Cable. iPhone Duo has a USB-C port and ships with a 1 m USB-C charge cable, per Apple's spec page, so it likely falls in the USB-C group, though the wired document doesn't name iPhone Duo.

The catch for Lightning owners: Apple's spec page lists only the phone and the USB-C charge cable in the box, so a USB-C to Lightning Cable is on you. More on that in what's in the iPhone Duo box.

Apple doesn't publish transfer speeds for either method, only that times depend on network conditions and how much data you're moving.

When an iCloud backup makes more sense

Restore from iCloud if the old phone is lost, broken or already traded in, or if you'd rather not tie up two phones at once. Apple's restore document has you tap From iCloud Backup on the Transfer Your Apps & Data screen, sign in, and pick the most recent backup after checking its date and size.

Apple says restore time depends on the size of the backup and your network speed. Photos, music and apps keep downloading after setup, so stay on Wi-Fi and power for a while afterward.

Make the backup as fresh as possible. Apple's iCloud backup instructions are Settings, then your name, then iCloud, then iCloud Backup, then Back Up Now, and the time of your last backup shows under that button.

A computer backup is the third option. Apple says Finder on a Mac with macOS Catalina 10.15 or later, or the Apple Devices app on a Windows 10 or later PC, can restore a backup over USB, and only an encrypted computer backup includes Activity, Health and Keychain data.

What doesn't transfer automatically

Biometrics and payment cards are the big ones. Apple's backup methods document says iCloud backups don't include Face ID or Touch ID settings or Apple Pay information and settings.

That matters more on iPhone Duo than on most iPhones. Apple's spec page lists Touch ID built into the side button and no Face ID, so you'll be enrolling fingerprints from scratch. Apple's Touch ID document puts this under Settings, Touch ID & Passcode, Add a Fingerprint, and you can enroll up to five fingerprints.

For Apple Pay, open Wallet, tap the Add Card button, and look for Cards Found For You, which Apple's Apple Pay setup document says lists cards you used previously.

Some data skips the backup because it already lives in iCloud. Apple says iCloud backups leave out Notes stored in iCloud, photos when iCloud Photos is on, and Messages when you sync them with iCloud, plus mail from services like Gmail and Exchange. It appears these return through iCloud sync and your account sign-ins rather than the backup, so expect to sign back in to non-Apple mail accounts.

Third-party apps vary: some may need a fresh login or their own restore step, so check important apps' help pages before you wipe the old phone.

If it doesn't work

The Quick Start prompt disappears or never shows. Apple's fix is to restart both devices and try again. If Quick Start keeps stalling, Apple points to a wired connection or a backup restore as the alternatives. Quick Start also won't work if the new phone is enrolled in Apple School Manager or Apple Business, per Apple.

Not enough iCloud storage for a backup. Apple offers free temporary iCloud storage when you buy a new iPhone and can't back up your current one. On the old phone, go to Settings, General, Transfer or Reset iPhone, then tap Get Started under Prepare for New iPhone. Apple gives you 21 days to restore that backup, another 21 days if you tap Keep My Backup Longer, and keeps it for seven days after you restore. Apple hasn't said how much storage the offer includes.

The restore asks for newer software. Apple says to update when prompted, then continue.

You bought apps with more than one Apple Account. Apple says you'll be asked to sign in to each; tap Skip this Step if you've forgotten a password and sign in later.

Bottom line

Quick Start is the easier route for most people moving to iPhone Duo, and an iCloud backup is the fallback when the old phone isn't available. Either way, budget time for the required update, then make sure your fingerprints are enrolled and your Wallet cards are re-added before you leave the house. More on what comes next: extending iPhone Duo battery life.

Which route did you take, and did anything fail to come across?