What Is an eSIM and How Does It Work?

Wondering what all the buzz is about with eSIMs? You might have heard that Apple started making their latest iPhones eSIMs only for specific countries or you might have seen an ad for it while planning a trip. Well, don’t fret - keep reading our full guide on what eSIMs are, the difference from traditional SIMs, how to set them up and where to buy them from.

What is an eSIM?

An eSIM is basically short for ‘embedded SIM’. It’s a digital version of the physical SIM card that’s been used for the past two decades. Instead of having a removable plastic chip that stores network credentials, an eSIM is soldered directly into your device during manufacturing. It’s mostly activated either through a QR code or manual inputs in settings.

The History of eSIM as a Defining Tech

eSIM tech was introduced into consumer smartphones in 2018 when Apple included it in the iPhone XR and XS. Since then, it has started becoming the standard feature across flagship devices from other brands like Samsung, Google, Xiaomi, etc. In 2022, Apple went further - they launched the iPhone 14 in the US as eSIM only with no physical tray at all. This was a signal that confirmed eSIM as the future of connectivity. 

eSIM vs. Physical SIM: What's the Difference?

Understanding what an eSIM is becomes much clearer when you put it side by side with what most people already know. 

A physical SIM is a removable card that fits into a tray on the side of your phone which stores the carrier's network credentials. If you travel internationally and want a local number, you need to physically swap cards. Lose it, damage it, or leave it at home, and you're out of luck.

An eSIM does everything a physical SIM does, but digitally. The credentials are downloaded rather than inserted. You can store multiple carrier profiles on a single eSIM chip simultaneously, switch between them and add a new plan from anywhere in the world. Most modern devices support having both a physical SIM and an eSIM active at the same time - known as dual SIM mode.

Here's a quick comparison:

Feature	Physical SIM	eSIM
Installation	Manual	Digital
Switching carriers	New SIM required	Download new profile
Travel flexibility	Swap cards abroad	Download travel plan instantly
Multiple numbers	Dual SIM tray needed	One chip, multiple profiles
Risk of loss/damage	Yes	No
Setup time	Minutes (if you have the SIM)	Under 2 minutes

The physical SIM is not going anywhere overnight - billions of devices still use them and will for years. But for anyone who travels, uses two numbers, or simply wants less friction in their connected life, the eSIM is a meaningful upgrade.

How Does an eSIM Work?

The mechanics of an eSIM are surprisingly straightforward once you understand the moving parts. Here's how the whole system functions from chip to connection.
The chip

It is a small piece of hardware embedded into your device's motherboard during manufacturing. It's compliant with a global standard set by the GSMA (the international body that governs mobile networks), which means it can work with any compatible carrier worldwide.

The profile 

This is the digital equivalent of what was stored on your physical SIM. Think your carrier's network credentials, your phone number, your plan details. When you purchase an eSIM plan, your provider generates a unique profile and delivers it to you, usually as a QR code or an activation code.

The Download Process

This is how the profile gets onto your chip. You scan the QR code through your device's settings and the profile downloads and installs - typically in under two minutes. Once installed, your phone registers on that carrier's network exactly as it would with a physical SIM.

Profile Switching

This is where eSIM really earns its place. If you have multiple plans stored - say, your home carrier and a travel eSIM - you can toggle between them in Settings without any physical action. Some devices allow two profiles to be active simultaneously, meaning you can receive calls on your home number while browsing data on your travel plan.

Data Roaming 

It works the same way as with a physical SIM, but with more control. When you're abroad, you can switch to a local eSIM plan specifically purchased for that destination, avoiding the roaming charges your home carrier would otherwise apply.

Understanding data roaming and how it interacts with your eSIM line is one of the most important things to get right before you travel.

What Phones Are Compatible With an eSIM?

eSIM compatibility has expanded dramatically since 2018. The short answer is that most flagship and mid-range smartphones released in the last four years support eSIM.
 
iPhones: Every iPhone from the XR and XS (2018) onwards supports eSIM. From iPhone 13 onwards, two eSIMs can be active simultaneously. iPhone 14, 15, 16, and 17 models purchased in the United States are eSIM-only - no physical SIM tray at all.

Samsung: eSIM support arrived with the Galaxy S20 series and has been standard across the S, Z Fold, and Z Flip lines since. Selected mid-range models including the A54, A55, A35, and A56 also support it.

Google Pixel: Google has supported eSIM since the Pixel 2 XL and includes it across every Pixel model from the 3 series onwards.

Other brands: Xiaomi, Motorola, Oppo, OnePlus, Sony, Honor, Vivo, and Nothing all have growing lists of eSIM-compatible devices across their current lineups.

Compatibility limitations: Hardware support alone isn't enough. Your device also needs to be carrier-unlocked. A phone purchased on a contract through a specific carrier may be locked to that network, blocking third-party eSIM profiles entirely. 

Tip: To check eSIM compatibility, dial *#06# and if an EID pops up, your phone supports eSIM.

How to Set Up an eSIM

Wondering how to install eSIM and set it up? up an eSIM is genuinely one of the more painless things you can do with your phone. The process differs slightly between iOS and Android, but the principle is identical across both.

On iPhone (iOS):

• Go to Settings > Cellular > Add eSIM
• Choose "Use QR Code" and scan the QR code
• Alternatively, tap "Enter Details Manually" and input the activation code
• Follow the on-screen prompts to label the line (e.g., "Travel" or "Work")
• Set the new line as your data line under Settings > Cellular > Cellular Data
• Enable Data Roaming on that line if you're using it abroad

Related: Check our data usage iPhone guide for an in-depth analysis on how to check usage, save data and cut costs.

On Android:

• Go to Settings > Connections > SIM Manager > Add eSIM
• Scan the QR code or enter the activation code manually
• Follow the prompts to download and install the profile
• Set it as your preferred data SIM under SIM Manager

The process for Android varies slightly by manufacturer - Samsung, Google Pixel, and Xiaomi each have slightly different menu paths. 

A few things to remember:

• eSIM installation requires an internet connection
• Most QR codes are single-use.
• Toggle airplane mode on and off to force your device to register on the new network
• Make sure data roaming is enabled on the eSIM line 

eSIM Benefits: Why Make the Switch?

The case for eSIM isn't just about convenience, though it is a significant part of it. Here are the benefits of eSIM and why the technology genuinely improves the experience of staying connected.

• Instant connectivity, anywhere.

With a physical SIM, getting connected in a new country means finding a store, buying a card, and hoping the staff can help you set it up. With an eSIM, you can buy eSIM online before you even board the plane, scan the QR code on arrival, and have local data working in under two minutes. 

• Travel without roaming charges.

One of the strongest arguments for eSIM is the ability to use a local data plan in your destination country without touching your physical SIM or buying a roaming package. The savings compared to international roaming packages from most home carriers are significant - often 60-80% cheaper per GB.

• Dual SIM without dual hardware. 

Before eSIM, using two numbers on one phone required a physical dual-SIM tray. But with eSIM, any compatible single-tray device can run two active lines simultaneously. 

• No physical SIM to lose or damage. 

It sounds minor until it happens to you - a lost SIM, a damaged tray, a card that got wet. The eSIM eliminates all of that. Your plan is stored digitally and can be redownloaded to a new device if yours is lost or replaced.

• Better for the environment

Physical SIM cards are small pieces of plastic that get discarded every time you switch carriers or travel. eSIM eliminates that waste entirely - no plastic, no packaging, no shipping.

Who Uses eSIMs?

The honest answer is: more people than you'd expect, across a wider range of use cases than most assume.

International travellers: They are the most obvious use case - and arguably the group that benefits most. Rather than paying roaming fees or hunting for a local SIM on arrival, they download a travel eSIM for their destination before they leave home.
 
Frequent business travellers: To maintain a local data presence in multiple countries without carrying a wallet full of SIM cards. A single eSIM-compatible phone can hold profiles for different regions and switch between them as needed.

Digital nomads: Those working remotely across different countries rely on eSIM for consistent, affordable connectivity without being tied to a single carrier's international plan.

Students studying abroad use short-term travel eSIMs to avoid eye-watering roaming charges from their home networks for the duration of their programme.

Everyday users who simply want to switch carriers without visiting a store -  eSIM makes that a settings menu action rather than a trip to the high street.

Travel Hack: Planning on traveling to the UK or just need data for everyday use? Grab a UK eSIM from dedicated provider like eSIM Cards and enjoy reliable connectivity.

Where Can I Buy an eSIM?

eSIMs are available from three main sources: your existing mobile carrier, device manufacturers through built-in plan stores, and dedicated eSIM providers.

Your existing carrier 

They may offer eSIM activation for your current plan - useful if you're simply converting your physical SIM to eSIM on the same network. This doesn't help with travel or getting a second number.

Built-in plan stores 

Like Apple's eSIM carrier search or Google's plan store let you browse and purchase plans directly from your device. Convenient, but limited in terms of plan variety and international options.

Dedicated eSIM providers 

They offer the widest range of plans - particularly for travel. These are where you'll find destination-specific plans, and unlimited data options at competitive rates. When choosing a provider, look for: clear data allowances, network transparency, instant QR code delivery, and responsive customer support. 

eSIM Cards offers plans across major networks with instant activation. You can download the eSIM cards app available for both iOS and Android and browse available plans from the comfort of your home.

eSIM Is the Future of Mobile Connectivity 

We hope this guide was able to answer the “what is an eSIM?” question. Remember - eSIM is not a niche technology for early adopters anymore. It's in the majority of new smartphones, supported by carriers all over the world, and it solves real problems - roaming costs, SIM logistics, device flexibility that have frustrated mobile users for years. 

If your device supports it and you haven't made the switch yet, the barrier to entry is genuinely low. Scan a QR code. eSIM is the most easiest way to do stay connected.

FAQs

Q1. What is an eSIM and how is it different from a regular SIM?

Ans. eSIM is a digital SIM card embedded directly into your device's hardware. Unlike a physical SIM, it doesn't need to be inserted or swapped - carrier profiles are downloaded and managed through your device's settings. 

Q2. Can I use an eSIM if I still have a physical SIM?

Ans. Yes, most modern smartphones support dual SIM mode, meaning a physical SIM and an eSIM can both be active simultaneously. You can receive calls on your regular number while using your eSIM for data, or assign different functions to each line. 

Q3. Is an eSIM more expensive than a physical SIM?

Ans. Not inherently. eSIM plans are priced comparably to physical SIM plans for everyday use, and for travel specifically they are often significantly cheaper than roaming packages from home carriers. The cost depends on the provider, the destination, and the data allowance.

Q4. What happens to my eSIM if I lose my phone or upgrade to a new device?

Ans. If you lose your phone, your eSIM plan can typically be reissued by your provider to a replacement device. Always check with your provider before assuming a transfer is automatic, as policies vary.