How Does an eSIM Work? A Plain-English Guide for Travellers

An eSIM works by downloading a mobile plan onto a secure chip that is already built into your phone, instead of loading it from a removable plastic card. You scan a QR code, the phone fetches an encrypted profile from the provider’s server, and a new line appears in your settings, ready to connect to a local network.

For travellers, that means you can buy data for your destination from home, install it on Wi-Fi in a couple of minutes and switch it on when the plane lands. This guide explains what an eSIM is, how the download really works, how it compares with a physical SIM, and what to check before you rely on one abroad.

What is an eSIM?

An eSIM (embedded SIM) does the same job as the SIM card you have known for years: it proves to a mobile network that your phone is allowed to connect, and it tells the network which account to bill. The difference is physical. A classic SIM is a removable card; an eSIM is a small secure chip soldered into the phone, technically called an eUICC.

The rules for how eSIMs work come from the GSMA’s eSIM whitepaper, published by the association that represents mobile operators worldwide. The GSMA describes the eSIM as a way to download a SIM securely into a secure element that is permanently embedded in a device. Because phone makers and operators follow the same specification, a travel eSIM from one provider installs on an iPhone, a Samsung Galaxy or a Google Pixel in the same basic way.

The chip itself never changes. What changes is the profile: the package of data that represents one mobile plan. According to the GSMA, one eUICC can hold several profiles, and each profile remains the property of the operator that issued it.

How does an eSIM work, step by step?

When people ask how an eSIM works, they usually mean: what actually happens between buying a plan and seeing bars on the screen? The GSMA’s consumer system is built from a few parts, and these are the ones you meet as a traveller.

Part	What it is	What it does for you
eUICC	The secure chip inside your phone	Stores one or more eSIM profiles
SM-DP+	The provider’s secure server	Prepares, encrypts and sends your profile
LPA	Software built into your phone’s settings	Downloads the profile and lets you switch lines on and off
Activation code	Usually shown as a QR code	Tells your phone which server to contact and which profile to collect

Here is the sequence, in plain English:

1. You receive an activation code. In most cases it arrives as a QR code by email. With ArriGo, the QR code reaches your inbox within about a minute of ordering.
2. You scan it on the phone. The GSMA explains that the QR code contains the address of the provider’s SM-DP+ server.
3. The phone connects to that server over Wi-Fi or another internet connection and proves its identity.
4. The server sends an encrypted profile that is made for your phone’s specific chip. The LPA installs it on the eUICC.
5. A new line appears in your mobile settings. You can label it, switch it on or off, and choose whether it carries your mobile data.

The whole exchange takes seconds once the scan is done. Most of the two minutes people spend on an eSIM install goes into reading the prompts and naming the line.

What is inside an eSIM profile?

A profile is a small encrypted file, not an app. The GSMA lists what it holds: the subscriber identity the network recognises (the IMSI), the SIM’s serial number (the ICCID) and the security algorithms and keys used to sign in to the network.

That is exactly what a plastic SIM contains. An eSIM is not a different kind of connection; it is a different way of delivering the same credentials.

eSIM vs physical SIM: what is the difference?

For everyday use at home, you would struggle to tell an eSIM and a physical SIM apart. The comparison changes when you travel, because swapping cards abroad is where most of the friction is.

	eSIM	Physical SIM
How you get it	Download, usually from a QR code	Card from a shop, kiosk or mail
When you can set it up for a trip	At home, before you leave	Usually after you land, at a store or kiosk
What happens to your home SIM	Stays installed alongside the travel line	Often removed to make room, then easy to lose
Plans stored on the phone	Several profiles at once	One per SIM tray slot
If the phone is lost or stolen	Cannot be pulled out and used in another phone	Can be removed and inserted elsewhere
Local phone number	Travel eSIMs are often data only	Local SIMs often include a number

Apple’s guide to using eSIM while travelling internationally makes the same points: an eSIM cannot be removed if your iPhone is lost or stolen, and you do not need to find, carry or mail physical cards.

The one thing a local physical SIM can give you that a data-only travel eSIM does not is a local phone number. For most trips that matters less than it used to, because calls and messages go through WhatsApp, iMessage, FaceTime and similar apps over data.

How does an eSIM work when you travel abroad?

The practical magic of an eSIM for travellers is that your phone can hold your home line and a travel line at once. You keep your Canadian number installed, and the travel eSIM supplies data on a local network.

Apple’s Dual SIM guide explains how this works on iPhone: two lines can be active, but only one line at a time uses cellular data. You decide which one in Settings → Cellular → Cellular Data (on some iPhones the menu is called Mobile Data). Android phones have the same choice under their SIM settings.

What happens when you land

When you switch on your phone at your destination, it sees the local networks and connects to one that your plan is allowed to use. Many travel plans can use more than one network in a country; ArriGo plans list them on each plan page, and our mobile networks page shows every operator we connect to.

Your phone treats any foreign network as roaming, so data roaming must be on for the travel line. That is normal and does not mean you are paying roaming fees: you are using the plan you already bought. On the other hand, leave data roaming off on your home line, or your Canadian carrier’s day pass could kick in. Apple notes that if you keep both lines active, your home line may still incur roaming charges from your carrier.

Apple also confirms that if you use only the travel eSIM for data, iMessage and FaceTime keep working with your home number. That is why most travellers barely notice the switch.

Tip: Install your travel eSIM at home on Wi-Fi a day or two before you fly. ArriGo plans only start counting days when the eSIM first connects at your destination, so installing early does not cost you any of your plan. Our guide to installing an eSIM before you fly has the steps for each phone.

Watch: setting up an eSIM on iPhone

Apple’s own video walks through the setup screens on iPhone. For written steps, Apple’s eSIM setup guide covers every method, including scanning a QR code.

Which phones support eSIM?

Most phones sold in Canada in the last several years support eSIM, but not every model does, and some phones sold in other regions leave it out. These are the official minimums from each manufacturer:

Brand	eSIM support starts with	Official source
Apple iPhone	iPhone XS, XS Max and XR	Apple’s eSIM setup guide
Google Pixel	Pixel 3a (physical SIM plus eSIM)	Google’s dual SIM help page
Samsung Galaxy	Galaxy S20 family, Z Fold and Z Flip lines, selected A models	Samsung Canada’s eSIM support page

A few details are worth knowing. Apple says iPhone 13 and later can run two eSIMs at the same time. Google says Pixel 7 and later can use two eSIM profiles if the carrier allows it. Samsung warns that a listed Galaxy model may still lack eSIM depending on the country it was made for, so a phone bought abroad is worth checking.

Our eSIM compatibility checker lists supported models by brand.

How to check your own phone in a minute

1. Look for an EID. The EID is the identifier of the eSIM chip. Apple’s guide to finding your iPhone’s serial number, EID and IMEI shows it under Settings → General → About (scroll down). If there is an EID, the phone has an eSIM chip.
2. Check the carrier lock. On iPhone, Apple says to open Settings → General → About and look for “No SIM Restrictions” next to Carrier Lock. If your phone is locked to Bell, Rogers, Telus or another carrier, ask them to unlock it before you travel.

Is an eSIM secure?

Yes. The GSMA states that an eSIM offers an equivalent level of security to a removable SIM card. Profiles are encrypted for one specific chip during download, and the servers that prepare them must pass the GSMA’s security accreditation before they can take part in the system.

There is also a physical security gain. A thief cannot slide an eSIM out of your phone and put it in another device, as Apple points out. On a Pixel, Google even lets you require your screen lock before anyone can delete an eSIM.

The one thing to protect is the QR code itself before you use it. Treat it like a gift card: anyone who scans it first could install your plan on their phone. Once it is installed on your phone, the code has done its job.

What a travel eSIM can and cannot do

Knowing the limits saves surprises on the trip. Here is what to expect from a prepaid travel eSIM like ArriGo’s:

• It is data only. You get mobile internet, not a local phone number or call minutes. Messaging and calling apps work over data.
• It installs on one phone. Each eSIM is made for one device. If two people are travelling, buy one eSIM per phone. ArriGo lets you buy up to 10 eSIMs in one order and send every QR code to yourself or each one to its own email address, which helps with sharing data across a family.
• It can usually share data. Most ArriGo plans allow hotspot, so a laptop or tablet can use your connection. The plan page shows this under “Coverage & networks”.
• It needs a compatible, unlocked phone. No eSIM chip, or a carrier lock, means no install.
• Do not delete it mid-trip. Erasing an eSIM removes the profile from the phone, and reinstalling may not be possible from the same code. Switch the line off instead, and only delete it once you are home.

How does an eSIM compare with roaming on your Canadian plan?

Roaming on your home plan is the simplest option, but in Canada it is billed by the day. As of October 2026, Bell’s Roam Better costs $13 a day in the US and $16 a day internationally, Rogers Roam Like Home costs $16 a day in the US and $18 internationally, and Telus Easy Roam costs $16 in the US and $18 internationally (all in Canadian dollars). Rogers also sells Travel Passes for 3 to 30 days.

A travel eSIM replaces that daily charge with a prepaid data plan that you choose in advance. Our Bell, Rogers and Telus roaming comparison breaks down when each option makes sense for your trip length.

Getting started with your first eSIM

An eSIM is a downloadable SIM: the plan arrives as a QR code, installs on a chip that is already in your phone, and connects to a local network when you land. Your home number stays where it is.

If you are new to it, the usual order is simple. Check that your phone is on our compatibility list, pick your destination, such as the United States, Mexico or Europe, install the eSIM at home, and switch it on after landing. If anything goes wrong, our help centre covers the most common fixes. When you are ready, find your destination and compare plans.