This works on iPhone XS, XR, SE (2020) and later, running a recent version of iOS. Do the install at home on Wi‑Fi a day or two before you fly.
1. Check your iPhone is unlocked
Settings → General → About → look for Carrier Lock. It should say “No SIM restrictions”. If it says anything else, contact your home carrier before buying an eSIM.
2. Install the eSIM profile
With a QR code (from the provider’s confirmation email):
- Settings → Cellular (or Mobile Service) → Add eSIM.
- Choose Use QR Code and scan it. If you’re reading the email on the same phone, choose the option to enter details manually or open the provider’s app instead.
- When prompted, label the plan — e.g. “Japan trip”.
With the provider’s app: many providers (Airalo, Saily, Nomad, aloSIM) can install the eSIM directly. Install the app, buy or open your plan, and tap Install eSIM — it hands the profile to iOS for you.
3. Set your lines up correctly
After install, iOS asks how to use each line. Set:
- Default Line / Voice: your home SIM (keeps your number for calls and 2FA).
- Cellular Data: the travel eSIM.
- Turn OFF “Allow Cellular Data Switching” so your iPhone can’t fall back to your home SIM’s expensive roaming.
4. On arrival: turn on roaming for the travel eSIM
- Settings → Cellular → tap the travel eSIM.
- Turn on Turn On This Line.
- Turn on Data Roaming (this is required — the eSIM’s “home” network is abroad, so it’s technically always roaming). It only affects this line.
- Make sure Cellular Data is set to the travel eSIM.
Give it a minute to find a network. If nothing happens, toggle Airplane Mode on and off, or restart.
5. When the plan ends
Top up in the provider’s app if supported, or remove the profile: Settings → Cellular → tap the eSIM → Delete eSIM. Deleting it frees a slot for your next trip.
Common problems
- No signal after landing: Data Roaming is off, or the wrong line is set for Cellular Data.
- Can’t scan the QR code: it’s on the screen you’re scanning with. Use the app, or open the email on a laptop.
- Messages/iMessage not sending: set iMessage and FaceTime to use your home number under Settings → Messages → Send & Receive.