How-to·11 Aug 2026·6 min read

How to install an eSIM on an iPhone

It takes about a minute over wi-fi, and it's worth doing at home rather than at the airport. Here's every step, plus the three things that usually go wrong.

Installing an eSIM is genuinely simple, but the first time you do it there's a moment of doubt — you're adding a second phone line to a device you rely on, and it isn't obvious what happens to the one you already have. Nothing happens to it. Your existing SIM stays exactly where it is, and this adds a second line alongside it.

Do this before you fly

Installation needs an internet connection, and your home wi-fi is the easiest one you'll have. Once installed, the plan sits dormant until you land — installing early costs you nothing.

Before you start

An iPhone that supports eSIM — broadly the iPhone XS and later, though iPhones sold in Mainland China have no eSIM support at all, and Hong Kong and Macao models mostly don't either.
A carrier-unlocked phone. If your handset is locked to a network, it will refuse the profile.
A wi-fi connection.
Your QR code, which we show you right after purchase.

If you're unsure whether your model qualifies, the compatibility list on our homepage is searchable and covers every brand we support, not just Apple.

Installing, step by step

Open Settings, then tap Cellular — it's called Mobile Data in the UK, Ireland, Australia and several other regions.
Tap Add eSIM. On iOS 16 and earlier this reads Add Cellular Plan or Add Data Plan.
Choose Use QR Code. If your iPhone offers Transfer From Nearby iPhone first, ignore it — that's for moving an existing line between devices.
Point the camera at the QR code. If you're reading this on the same phone, tap Enter Details Manually and paste the activation code instead.
Tap Continue, then Add eSIM. The profile downloads in a few seconds.
Label the line when prompted. Choose something like Travel or Japan rather than accepting Secondary — you'll be picking between lines in menus for the rest of the trip.
Choose which line does what on the screens that follow. This is the important part, and the next section covers it properly.

Setting which line does what

After installing, iOS asks three questions in a row. Most people tap through them, then wonder later why something isn't working. Here's what each one means.

Default Line

This is the line used for calls and texts. Leave it as your usual number. Your travel eSIM is data-only — it can't make calls or send SMS, so setting it here would break your phone in a way that's confusing to diagnose.

iMessage & FaceTime

Leave this on your usual number too. Your contacts message the number they already have for you, and it works over whichever data connection is active.

Cellular Data

This is the one to change — but only once you land. Set it to your travel eSIM and all data goes through the plan you bought instead of your home carrier's roaming rates. If you switch it before you leave, you'll spend your travel data at home.

Turn off data roaming on your home line

In Settings → Cellular → your home line → Cellular Data Options, switch Data Roaming off. It's the single most effective thing you can do to guarantee no surprise bill: even with the eSIM carrying data, background services can otherwise reach for your home line.

When you land

Two things, both quick. Set Cellular Data to your travel eSIM if you haven't already, and make sure the travel line is switched on in the Cellular menu. Your phone finds a local network by itself within a minute or two — there's nothing to configure beyond that.

This is also the moment your plan starts. The clock runs from first use on a network at your destination, not from purchase or installation, so buying weeks ahead costs you no validity.

The three things that usually go wrong

The QR code won't scan

Almost always because you're reading it on the phone you're installing to. Use Enter Details Manually and paste the activation code, which we show alongside the QR code for exactly this reason. Failing that, display the code on a laptop and scan it from there.

"Unable to add cellular plan"

Three usual causes: the phone is carrier-locked, it's a Mainland China, Hong Kong or Macao model without eSIM support, or the profile was already installed once. An eSIM profile can generally only be installed a single time — if you deleted it, you'll need a replacement rather than a retry.

It installed but there's no signal

Check the travel line is enabled and selected for Cellular Data, then toggle Airplane Mode on and off to force a fresh network search. If it still won't attach after a few minutes, restart the phone. If nothing works, get in touch — a profile can occasionally fail on the provider's side, and that's on us to fix.

Installing more than one eSIM

Recent iPhones can store several eSIM profiles at once — typically eight or more — though only two lines can be active simultaneously. In practice that means you can keep last year's Japan eSIM installed while adding one for this year's trip to Italy, and simply switch which is active.

Where this becomes genuinely useful is a multi-country trip. Install each destination's eSIM before you leave, then enable each one as you arrive. There's no scrambling for wi-fi in an unfamiliar airport to buy the next one.

A regional plan often avoids the problem altogether. If you're crossing several borders in one region, one eSIM covering the whole area is simpler than four covering a country each — and usually cheaper.

After the trip

Set Cellular Data back to your home line. You can leave the travel eSIM installed — an expired one uses nothing and takes no space — or delete it from Settings → Cellular → the line → Remove eSIM. Delete it only when you're sure you're done, because a deleted profile can't be reinstalled from the same QR code.