Eleven questions people ask before buying their first travel eSIM

1. Will it work on my phone?

Your phone needs eSIM hardware and it needs to be carrier-unlocked. Almost every flagship from the last five years has the hardware; the lock is the more common problem.

The quick test: dial *#06# in the phone app. If the screen shows an EID — a 32-digit number — the hardware is there. It does not tell you whether the phone is locked.

Worth knowing: some models ship differently by market. iPhones sold in mainland China have two physical SIM slots and no eSIM, and a few Samsung and OnePlus regional variants leave it out.

2. Do I lose my own number?

No. The travel eSIM is a second line. Your existing SIM stays in the phone and keeps receiving calls and texts on your usual number — you simply choose the travel line for mobile data.

That is the arrangement most travellers want: your number reachable for the bank's two-factor code, the data running over something that does not cost £3 a day.

3. When does the clock start?

Installing the eSIM does not start it. A package starts the first time the eSIM connects to a network in a country that package covers — even if mobile data is switched off on that line.

So: install at home over Wi-Fi, leave the line switched off, and turn it on when you land. The one exception is if your home country happens to be covered by the package you bought, in which case it will start the moment the line connects at home.

4. Can I share it — hotspot, tethering, a laptop?

Yes. Personal hotspot and tethering work on every onesim package. What you share comes out of the same allowance, so a laptop pulling a software update through your phone counts like any other use.

5. Can two phones share one eSIM?

No. An eSIM profile lives on one device. Two phones need two lines.

What you can do is hotspot from the phone that has it, which is how most couples and families do it: one package, one phone as the hub, everyone else connected to it.

6. What happens when I get a new phone?

You transfer it. With no active package, you move the eSIM yourself in the app — the new phone gets the eSIM and the old one is deactivated. With an active package running, contact support and they move it for you.

7. Do I need a new eSIM for every trip?

No, and this is the part people find genuinely surprising. Your account has one eSIM. Keep it on the phone, and when you go somewhere else, buy a package for that destination — it attaches to the eSIM you already have. Nothing to install again.

Each package carries its own coverage, allowance and validity.

8. What if I run out of data?

It stops. It does not continue at a roaming rate and it does not generate a bill. Buy another package from the website or the app and it attaches to the same eSIM.

This is the practical reason to buy the smaller package when you are unsure: being wrong costs two minutes.

9. Does Wi-Fi use my package?

No. Only traffic over the mobile network counts. Hotel and café Wi-Fi is free as far as your allowance is concerned, which is why most people use much less than they expect.

10. What about several countries in one trip?

That is what a regional package is for — one package, one allowance, a list of countries it covers. The data is shared across all of them and crossing a border does not restart anything.

The thing to check is the list. "Europe" is a list of specific countries, and the ones people assume are on it — Switzerland, the UK, Türkiye, the Balkans — are not always on everyone's.

11. Can I call and text?

Travel data packages like ours are data only: no local number, no SMS. Calls go over WhatsApp, FaceTime, Signal or any other app, which is what most people use anyway.

For SMS two-factor codes, keep your own line on to receive texts. That costs nothing as long as its data roaming is off.

What to check before you pay