What is an eSIM and how does it work?

What is an eSIM?

eSIM is short for embedded SIM. It's a small chip fixed inside the phone that does the same job as a SIM card: it holds the details that let a mobile network recognise your phone and connect it. The difference is that nothing is inserted. Your mobile plan arrives as a download, which is why an eSIM is sometimes called a digital SIM.

The downloaded plan is called a profile. A plastic SIM card carries one operator's profile, fixed at the factory. An eSIM can store several profiles at once, and you add or remove them in your phone's settings. That's what makes it handy for travel: your home plan stays on the phone, and a travel plan sits beside it.

You may also see the term virtual SIM. The chip is real enough; it's the plan that comes over the internet rather than in the post. eSIM is an industry standard, so the same eSIM works with operators all over the world, as long as your phone supports it and isn't locked to one carrier.

How does an eSIM work?

When you buy an eSIM plan, the seller sends you a QR code. The code holds two things: the address of the server that stores your profile and a one-time activation code. When you scan it, your phone contacts that server over the internet, downloads the profile and installs it as a new line, listed in settings next to your usual SIM.

From then on the phone treats the eSIM like any other SIM. When you arrive at your destination, the travel eSIM connects to a local network there. A travel eSIM normally does this by roaming, so the eSIM line's own data roaming setting needs to be on. On a prepaid travel plan that costs nothing extra: you've already paid for the data. What you want to avoid is your home SIM roaming, so you set the eSIM as the line for mobile data.

Two practical points follow. Installing needs an internet connection, so it's easiest at home on Wi-Fi before you travel. And the activation code normally works once, so don't delete an installed eSIM to make room for another; phones keep several side by side.

eSIM vs physical SIM card

What is a travel eSIM?

A travel eSIM is a prepaid data plan for the country or region you're visiting, delivered as an eSIM. You buy it before you go, install it at home, and use it for mobile data while you're away. Your usual SIM stays in the phone, so you can still take calls and texts on your own number if you want to (your home provider's roaming rates apply to those).

Plans come in three shapes. A country plan covers one country. A regional plan covers several on one eSIM, such as our Europe and Asia plans. A global eSIM covers well over a hundred countries, for trips that cross several regions. Our plans are data only: there's no local phone number, and messaging and calling apps such as WhatsApp work over the data. Most of our plans start when you first connect at your destination, not when you buy them, and each plan card says when its days start.

Does my phone support eSIM?

Most recent smartphones do. On iPhone that's the XS, XS Max and XR onward; on Google Pixel, the Pixel 3 onward, with a few early exceptions; on Samsung, the Galaxy S20 series onward and the foldables. Many other Android phones support it too, but it varies by model and by the country it was sold in.

The quickest check is to dial *#06#. If the screen shows an EID number, your phone has an eSIM. The phone also needs to be carrier-unlocked, which matters if you bought it on contract. Our list of eSIM compatible phones goes model by model.

How to install an eSIM

1. Connect to Wi-Fi you trust. The phone needs the internet to download the eSIM.
2. Open the QR code from your order email on another screen, or print it. On iPhone go to Settings, then Mobile Service (Cellular), then Add eSIM. On Android open your SIM settings and choose to add an eSIM. Then scan the code.
3. Give the new line a name you'll recognise, such as “Travel”.
4. Set the travel eSIM as the line for mobile data, and keep your usual line for calls and texts if you want them.
5. When you land, turn on data roaming for the travel eSIM line only.

Can't scan the code? Most phones also let you type in the details by hand. Our install troubleshooting walks through each step for iPhone, Samsung and Pixel.

How to top up an eSIM

With many travel eSIMs you can add data to the eSIM you already have instead of buying a new one. On ours, open your order page from the link in your order email, or log in to your account, and tap Top up on the eSIM. You choose more data, or more days on a daily plan, pay, and it's added to the same eSIM within a minute or two. There's nothing new to install. Each plan card says whether that plan can be topped up. See how to top up for the steps.

Is an eSIM cheaper than roaming?

It depends on your home provider, so check what they charge for data in the country you're visiting: some include it, some sell a daily pass, and some charge by the megabyte. Then compare that with the price of a travel eSIM for the same trip.

For a sense of our prices: our plans start at $1.03, card fees included. Here's what 5 GB for 30 days costs today:

• Japan: $4.32
• United States: $4.80
• Mexico: $10.11
• Italy: $3.81
• Thailand: $4.32

Every country and size is on our price list, updated hourly, with the cost per GB for each plan.

How to choose the best travel eSIM

There isn't one best eSIM for everyone. These are the things worth checking on any plan, ours included:

• Coverage. Does it cover every country on your route? Regional plans vary in their country lists.
• Networks. Which local networks does it use, and at what speed? Plans that can use more than one network help where coverage is patchy.
• 5G. Only matters if the plan lists 5G and your phone supports it.
• Data and days. Pick an allowance that fits how you use your phone, and a validity at least as long as the trip.
• When it starts. Most plans start on first connection at your destination, some on install.
• Top-ups. Being able to add data to the same eSIM lets you start small.
• Price per GB. The cheapest plan is rarely the best value; compare the cost per GB.

Our price comparisons put our plans next to other sellers', including where they're cheaper, and the plan list filters by data, days and price.

eSIM FAQ

Can I keep my WhatsApp number with a travel eSIM?

Yes. WhatsApp is tied to your account, not to the line carrying your data, so it keeps your usual number while the travel eSIM provides the data.

Can I have more than one eSIM on my phone?

Yes. Most eSIM phones can store several eSIM profiles and switch between them in settings. How many can be active at the same time depends on the phone; many recent phones run two lines at once.

Can I use an eSIM and a physical SIM at the same time?

On a dual-SIM phone, yes. A common setup for travel is your usual SIM card for calls and texts and a travel eSIM for mobile data.

Does installing an eSIM need Wi-Fi?

Installing needs an internet connection, because the phone downloads the eSIM. Wi-Fi at home is the easy option. After that the eSIM uses mobile networks and doesn't need Wi-Fi.

What happens if I delete my eSIM?

An eSIM's activation code normally works only once, so a deleted eSIM usually can't be reinstalled from the same QR code. Don't delete one to make room for another; phones hold several side by side. If it happens, contact the seller.

What is the best eSIM for international travel?

The one that fits your trip, judged on a few things: whether it covers every country on your route, which networks it uses there, whether the data and days fit how you'll use it, when the days start, whether you can top it up, and the price per GB. A plan for one country is usually cheaper than a regional or global one if you're staying put.

Can I use an eSIM in a tablet?

Yes, if the tablet has mobile data and supports eSIM, as many Wi-Fi + Cellular iPads and some Android tablets do. A Wi-Fi-only tablet can't use one.

Does a travel eSIM give me a local phone number?

Ours don't: they are data only, with no phone number, calls or regular texts. Some providers sell plans with a number; check before you buy if you need one.