How to Make and Take Calls on a Data-Only eSIM

Most travel eSIMs are data only. They give you an internet connection in the destination country and no phone number there, so nothing can dial the eSIM and the eSIM cannot dial out in the ordinary sense.

That sounds more limiting than it is. Anything that runs over the internet works normally, and your own number can keep working too — the piece most people are missing is free and takes one switch.

This is the answer for the calls that actually matter: the bank, the airline, the person who only has your real number.

Turn on Wi-Fi Calling before you leave. Calls and texts to your normal number then arrive over any wifi connection, billed as if you were at home, while the travel eSIM handles data everywhere else. Apple’s setup takes one screen, and on Android the toggle sits under Network & internet, SIMs, Wi-Fi calling — if it is not there, your carrier does not support it.

For everything else, the travel eSIM’s data is enough on its own:

• WhatsApp, Signal, FaceTime, Messenger and the rest place voice and video calls over data. Voice is cheap — roughly a tenth of what video costs.
• Both parties need the same app, which is the only real constraint and usually not one.
• A voice call runs at roughly 30 to 60 MB per hour, so even a small plan supports a lot of talking. Set against what the rest of a trip consumes, calling is rarely what sizes the plan.

When you need to reach a landline or someone with no messaging app — a restaurant, a taxi office, a hotel — a paid VoIP service places the call over data to a normal number, usually for a few cents a minute.

Worth setting up before you travel rather than while standing outside a closed restaurant, since most require an account and a small balance.

Being reachable on a local number. If you need one — for a delivery, a local booking, an app that insists on a local mobile — a data-only plan cannot provide it.

Not calls. Banks and login flows send codes by SMS to your registered number, and a data-only eSIM cannot receive them. Wi-Fi Calling closes that gap for most carriers, which is the strongest argument for switching it on before a trip — the full set of ways to get a bank code abroad is worth reading before you need one.

Where it does not, moving the account to an authenticator app before you travel is more reliable than hoping — and better practice regardless. NIST’s digital identity guidelines treat one-time codes sent over the phone network as a restricted authenticator, so you are moving with the grain rather than against it.

If your calling is app-based, a data-only plan is all you need and the cheapest per GB wins. If you genuinely need a local number, filter for it and expect to pay more. Plans by destination, ranked on price per GB.