What is an eSIM?
An eSIM is a SIM card that is built into your phone instead of being a piece of plastic you insert. It does the same job — it tells the phone which mobile network to use and lets it connect — but you add a plan by downloading it rather than swapping a card.
How an eSIM works
Every phone that supports eSIM has a small chip on its board that can hold one or more mobile plans. A plan arrives as a digital profile. Installing it is a download: your phone contacts the provider, receives the profile and adds it as a new line.
Because nothing is physically swapped, you can keep your normal SIM in place and add a travel plan next to it.
eSIM or a physical SIM card
A physical SIM is a card you buy, collect and insert. An eSIM is bought and installed on the phone itself, so there is no shop to find and no card to lose.
Phones that support eSIM can generally use two lines at once, so you can keep your own number active for calls and messages while your mobile data runs on the travel plan.
Why travellers use one
A travel eSIM gives you mobile data at your destination for a price you pay once, up front. You can install it at home and switch it on when you land.
Your home operator does not charge you for data abroad as long as data roaming is turned off on your home line — your phone uses the travel plan for data instead.
What you need
A phone that supports eSIM. iPhone XS, XS Max, XR and every iPhone after them do.
A phone that is not locked to one network by your home operator.
An internet connection to download the eSIM. Wi-Fi at home or at the airport is enough.
What a Voyafi eSIM is not
Voyafi plans are data-only. They give you mobile internet at your destination, not a local phone number, so they do not carry voice calls or SMS. Your usual number stays on your phone for that.
