What Is an eSIM and How Does It Work?
An eSIM is a digital SIM built into your phone. Learn how it works, how it differs from a physical SIM, and how travellers use one for data abroad.
An eSIM is a digital SIM that is built into your phone, so you can add a mobile plan without inserting a plastic SIM card. Apple describes it as "an industry-standard digital SIM built into your iPhone". This guide explains what an eSIM is, how it works and why travellers use one for mobile data abroad.
What is an eSIM?
An eSIM ("embedded SIM") is a SIM chip that is soldered inside your phone instead of being a removable card. You add a mobile plan to it by downloading a profile, usually by scanning a QR code.
The profile holds the same information a physical SIM card holds. It tells your phone which network to connect to and which plan you are using. The only difference is that it arrives as a download instead of in the post.
How does an eSIM work?
You buy a plan, receive a QR code or activation details, and your phone downloads the plan onto its built-in eSIM chip. When the plan is active, your phone connects to the mobile network named in that plan.
The steps are usually the same on every phone:
- Check that your phone supports eSIM and is carrier-unlocked.
- Buy an eSIM plan.
- Scan the QR code, or enter the activation details by hand.
- Choose which line your phone uses for mobile data.
Your phone needs an internet connection for the download. Apple notes that your iPhone "must be connected to a Wi-Fi network or hotspot" to set up eSIM in most cases. Our step-by-step install guide covers iPhone and Android.
What is the difference between an eSIM and a physical SIM?
A physical SIM is a removable card that you swap by hand, while an eSIM is built in and you add plans by download. Both connect you to a mobile network in the same way.
Physical SIM | eSIM | |
|---|---|---|
How you get it | In a shop or by post | Download, usually by QR code |
Swapping plans | Remove and insert a card | Change the active line in Settings |
Plans on one phone | One per SIM slot | Several stored; supported iPhones run two active at once |
If the phone is lost | The card can be removed | It can't be removed from the phone |
Phone support needed | Any phone with a SIM slot | eSIM-compatible, unlocked phone |
Why do travellers use an eSIM?
Travellers use an eSIM to get local mobile data abroad without looking for a SIM shop at the airport. You can buy and install the plan before you leave home.
It also lets you keep your normal SIM in the phone. Apple says that if your iPhone has a SIM tray, you can "use both a physical SIM and an eSIM while travelling internationally". Your home number stays on your physical SIM, and the travel eSIM handles data.
Simnetic tip: Every Simnetic plan shows its data, validity and price before you pay, so you can compare plans for your destination before you install anything.
Does an eSIM work in every phone?
No. Your phone must support eSIM and be carrier-unlocked. iPhone XS, XS Max, XR and later models support eSIM, but phones sold in some countries or locked to one network may not.
On Android, support depends on the exact model and where it was sold. For example, Google says some Pixel 3 phones bought in Australia, Taiwan and Japan don't work with eSIM. Our guide on checking if your phone supports eSIM shows how to check.
Does a travel eSIM come with a phone number?
Most travel eSIMs are data-only, so they do not include a phone number. Simnetic eSIMs are data plans, and there are no phone numbers included with them.
You can still use apps for calls and messages over data. If you need a separate number, that is a different product, a virtual phone number.
Is an eSIM safe?
An eSIM is at least as secure as a physical SIM. Apple says eSIM "can't be removed if your iPhone is lost or stolen", so a thief cannot pull it out and put it in another phone.
As with any SIM, protect your phone with a passcode. Only install eSIM profiles from providers you trust.
How do I get an eSIM for my next trip?
Choose your destination, pick a plan with enough data for your trip, then install it before you travel. You can see every plan's data, validity and price before you pay.
Browse eSIM plans for 217 countries on Simnetic.
About the author: Written by the Simnetic team at Domaxit LTD, a London-based provider of prepaid travel eSIM data plans for 217 countries and virtual phone numbers. We check every price and plan detail in our articles against the live Simnetic catalogue before publishing.