Questions, answered.

A SIM that is built into your phone instead of a plastic card. onesim sends you a data profile to install; once it is on your phone, it connects to local networks the same way a regular SIM would — no swapping, nothing to lose.

Most phones from 2019 on support eSIM, and the phone needs to be carrier-unlocked. The quickest way to be sure is to check your model in the compatibility guide before you buy. Check compatibility

Yes. onesim is data-only, so your regular SIM stays in your phone for calls, texts and your WhatsApp number. Keep in mind your regular carrier may still charge roaming fees for calls, texts or data on that SIM — turning off its data roaming avoids surprises.

No — onesim provides mobile data only. Calls and messages through apps like WhatsApp, FaceTime or Telegram work over that data. Standard phone calls and SMS still go through your regular SIM at your carrier’s rates.

Search for your destination and we show the package that covers it — onesim sells regional packages, so Spain is covered by the Europe plan, Thailand by the Asia plan, and so on. If your trip crosses several countries in the same region, one regional package covers all of them. Then pick the data amount and validity that fit your trip.

Choose a regional package whose coverage list includes every stop on your route. One eSIM and one package then work across all of them — no switching between countries. Open Coverage on any package to see the full country list. Explore regional packages

Yes. One allowance for the whole package — use it in any mix of the included countries. It is not per country and does not reset when you cross a border.

The package will not connect there. Check whether another onesim package covers that stop, or plan on Wi-Fi for it.

Maps, messaging and browsing use roughly 1–2 GB a week for most people. Video calls and streaming use far more. When in doubt, start smaller — you can add a package during your trip. Choosing a package

Installing the eSIM does not start the clock. Your package starts the first time the eSIM connects to a network in a country it covers, even while mobile data is off. Install at home over Wi-Fi and keep the onesim line switched off until you arrive; if your home country is covered too, the package would start the moment the line connects there.

Install while you still have internet. Open the “Access your eSIM” link from your email or use the onesim app, then follow the steps for your phone. Keep data roaming off for the onesim line until you arrive. Installation guide

No. Validity runs from your first connection in any included country and continues for the plan’s full duration wherever you are on the list.

Turn the onesim line on, enable data roaming for that line only, and select it for mobile data. Keep your usual SIM for calls. If nothing happens after a few minutes, toggle airplane mode. Connecting when you arrive

Yes. Personal hotspot and tethering are allowed on every onesim package, so you can share your data with a laptop, a tablet or a travel companion. Shared data counts against the same allowance.

No. You can buy on the website and receive an email with a link to access your eSIM. The app is optional — it makes installation easier and lets you check remaining data and top up.

Yes. Your account has one onesim eSIM, and you refill it with any regional package from anywhere in the world — from the website or the app. The new package is added to the eSIM already on your phone; there is nothing to install again.

Website purchases come with an “Access your eSIM” link by email; request a fresh one from the recovery page if it expired. In the app, sign in with the same email address you used at purchase. Can’t find your purchase?

Yes. Every account has one eSIM for good: keep it on your phone and buy a package for the next destination — it is added to that eSIM. Each package has its own coverage, allowance and validity.

Yes. With no active package, you transfer the eSIM yourself in the onesim app: the new phone gets your eSIM and the old one is deactivated. With an active package, contact support and we move it for you. Only one transfer is possible within a short period, so start it once the new phone is set up.

Check the onesim line is on with data roaming enabled and selected for mobile data, then confirm the country is on your package’s list. Toggle airplane mode or restart. Don’t delete the eSIM — contact support instead. Troubleshooting steps

Common causes: a carrier-locked phone, unstable Wi-Fi, or a profile that is already installed under another name. Check your list of lines before trying again. What to check

If a package cannot be installed or used, the refund policy explains what applies. Contact support with your order reference and we’ll check it with you. Read the refund policy

Message the onesim support team from the app or the website. Have your order reference handy, and never share your QR or activation code in a public channel. Contact