How to Install an eSIM

Installing an eSIM takes about two minutes on wifi. Almost everything that goes wrong is one of three things: scanning the code in the wrong place, installing it too late, or forgetting which line the phone is meant to use once you land.

• A wifi connection. Downloading the profile needs internet, and you will not have mobile data yet.
• A phone that supports eSIM and is not carrier-locked. Dial *#06# — if an EID appears next to the IMEI, the hardware is there. A locked phone can still refuse other networks.
• The QR code from your provider, on a screen you can point the phone at, or ready to install directly.

1. 1Open the eSIM screen. iPhone: Settings → Cellular → Add eSIM. Android: Settings → Network & internet → SIMs → Add SIM → Set up an eSIM, which is the path Google gives for setting up a new eSIM. Scanning the code with the camera app sometimes works — Apple supports it explicitly — but going through settings always does.
2. 2Scan the code and let the profile download. This is the only step that needs wifi, and it takes a few seconds.
3. 3Label the line. The phone will offer names like "Secondary" — change it to the country or provider. When you are standing in an airport deciding which line to switch on, "Japan" is a great deal clearer than "Secondary".
4. 4Leave it turned off until you arrive, unless the provider says otherwise. Then turn it on, set it as the data line, and enable data roaming for it.

Three toggles account for nearly every "it does not work" message providers receive, and all three are on your phone rather than their end.

Data roaming, on the travel line

This one catches nearly everyone. A travel eSIM is roaming from its home network’s point of view even though you are paying local rates, so with data roaming off it will not connect. Turn it on for the travel line specifically.

Data roaming, off on your home line

The mirror image, and the expensive one. Your home SIM should stay active to receive calls and texts, but its data roaming should be off, or the phone can quietly bill you your carrier’s roaming rate for background traffic while the eSIM sits unused.

Which line sends messages

Set the travel line for cellular data and leave your home line as the default for calls and SMS. Most travel eSIMs are data only and have no number, so texts sent from that line would simply fail. Apple walks through the per-line defaults in its guide to using Dual SIM with an eSIM, including the automatic data switching that can quietly move you back to the wrong line during a call.

• The QR code will not scan: ask the provider for the manual details — an SM-DP+ address and activation code — and enter them by hand on the same screen. Same result.
• "Unable to add eSIM": usually the code has already been used. A profile can generally be installed once, so if you scanned it on another phone you need it reissued.
• Installed but no signal after landing: check data roaming is on for the travel line, then select the network manually in settings rather than waiting for automatic selection.
• Connected but nothing loads: turn airplane mode on and off. If that fails, restart. Between them these fix most first-connection problems.

Two things worth checking, because they decide whether you are doing this again mid-trip: whether the plan can be topped up on the same eSIM, and — for anything sold as unlimited — the daily cap after which speeds drop. We show both alongside price per GB for every plan we track, by destination.