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Mobile phone eSims explained: what is an eSim and how does it work?
Adam covers home improvements and mobile networks, splitting his time investigating topics from bathrooms to phone contracts. He was shortlisted at the BSME Talent Awards 2024.
A Sim is an essential part of your mobile contract: it tells your phone which mobile network it is connected to and what your phone number is. Since the early 1990s, Sim cards have been a physical object you insert into a phone.
However, there is an alternative: eSims launched in 2016 to little fanfare and have struggled to really take off, but are gaining popularity.
The GSMA, a trade association for mobile networks across the world, predicts that by 2030, 6.9 billion smartphones and 76% of mobile connections will use them, so what are the benefits, and is it worth replacing a physical Sim card? Read on for more.
- eSims are a virtual alternative to physical Sim cards, allowing users to switch easily between networks without physically changing a card. They are activated using an app or QR code.
- eSims offer convenience, flexibility and better coverage options for travellers or those frequently switching networks. They’re also useful if you need different profiles for work and personal use.
- Security advantages include the fact that there's no physical Sim card to remove, and the ability to disable an eSim on a lost device remotely, thereby preventing unauthorised access.
- eSims are offered by major mobile networks in the UK, such as EE, Vodafone, and O2, alongside smaller networks like Lebara, Giffgaff and iD Mobile. Phone compatibility has expanded across major brands such as Apple, Samsung and Google.
- As device manufacturers increasingly support eSims, and as consumer awareness grows, eSim adoption is expected to significantly increase, with predictions of 76% of smartphones using them by 2030.
What is an eSim?
Sim cards have got slimmer over the years, from the Mini Sim in 1996 and the Micro Sim in 2003 to the Nano Sim in 2012. Then, in 2016, the first eSim was launched in a Samsung Gear S2 smartwatch.
An eSim effectively acts as a virtual Sim card that's built into the phone; it's occasionally referred to by its technical name, an embedded universal integrated circuit card (eUICC). An eSim can be connected to any mobile network that offers eSim services.
New smartphones, tablets and laptops increasingly come with eSim capabilities.
An eSim shouldn’t have any different impact on network performance or signal strength compared to a physical Sim, but it’s good to know which provider has good coverage. You can find the mobile networks with the best signal in your area by reading our mobile coverage guide.
How does an eSim work?
Instead of removing a physical Sim card and inserting a new one when you want to change mobile network, you download an eSim profile, by either using an app or scanning a QR code.
You then pick an eSim plan and can start using it immediately, as the relevant information from the network will be installed directly to your phone. It’s possible to have both a physical Sim and an eSim. You can swap between the different networks on each Sim by going to your phone settings:
- Apple devices: Mobile data – Data Plans.
- Samsung devices: Connections – Sim Card Manager.
It’s also possible to store more than one eSim profile at the same time, but you can only be actively using one at any one time.
We spoke to Kathiravan Kandasamy, VP of product management at Syniverse, a company that produces software and systems for mobile networks. He explained why an eSim being installed directly to your phone brings additional security benefits: 'As a digital version of a physical Sim integrated into your phone, an eSIM cannot be physically removed from your device and used in another device. If the device is lost, the eSim can be disabled remotely, ensuring your device is not accessed by unauthorised users.'
Changing your mobile provider is easier than ever. Find out more in our guide on how to switch mobile provider. Or if you're in the market for a new handset, our mobile phone reviews highlight great value models for under £200.
What are the benefits of an eSim?
There are a variety of benefits to using an eSim, particularly if you travel a lot or use different Sim plans:
- Convenience There's no need to go to a store or wait for a Sim card to be sent to you when you want to change network.
- Flexibility You can maintain multiple eSim profiles, each with different numbers, and switch to the appropriate Sim for different contexts, such as for work or travel abroad. This could be particularly useful while roaming, allowing you to switch to a local network, or a provider that offers better roaming fees at your destination.
- Coverage Swap to a network with better coverage if you are often in different areas with variable signal strengths.
There are minor downsides to eSims for mobile customers, depending on how you use your Sim plan. An eSim makes it more difficult to swap one plan between multiple devices, as it’s not like a physical Sim card where you can just remove it from a phone and insert it into a different one. If you often need to do this, you'll have to go through the eSim activation process each time you want to swap your plan between different phones.
Overall though, eSims are likely to become increasingly common and provide a better option for consumers than a physical Sim card.
Kandasamy said: 'Customers can shop online for the eSim options before visiting a holiday or business destination, and purchase the plan online without the need or hassle to look for a physical SIM upon arrival at the destination. Typically, many devices allows for multiple eSims to be used – so you can have multiple networks loaded on your phone, such as my home phone number as well as a travel plan. This allows users to receive phone calls or SMS messages as normal when travelling. It can also allow you to use the travel eSim for data and browsing so you won’t have to pay expensive roaming charges when abroad.'
Read our guide on five ways to save while roaming to see how picking the right network could help you cut your bills.
Which UK mobile networks offer eSims?
An eSim won't cost you any more or less than a physical Sim card plan, but it can be more flexible. Most UK networks now offer eSims, including:
- 1p Mobile
- EE
- Giffgaff
- Honest Mobile
- iD Mobile
- Lebara
- Lycamobile
- Mozillion
- O2
- Sky Mobile
- Smarty
- Spusu
- Talkmobile
- Tesco Mobile
- Three
- Vodafone
- Voxi
For detailed reviews of all aspects of mobile provider performance, read our mobile phone provider reviews.
Is my phone eSim compatible?
You'll need to make sure your mobile phone is compatible with an eSim. The Google Pixel range has had eSim capabilities since 2017 (Pixel 3a and later), the Apple iPhone range since 2018 (iPhone XS and later) and Samsung Galaxy range since 2020 (S20 series and later).
Every iPhone from the iPhone 11 to the iPhone 14, including, Pro, Pro Max and Mini versions, can use eSims. Similarly, the Samsung Galaxy range from S20 and S23, including Note and Z Flip versions, are able to use eSims.
The first eSim-only device was the Motorola Razr, which does not support a physical Sim card at all.
More recently, the iPhone 17 Air launched worldwide as eSim-only. Standard iPhone 17 and iPhone 17 Pro/Pro Max continue to have space for a physical Sim card in most countries, but are e-Sim only in the US, Canada and Japan.
For advice on what phone to purchase to suit your needs, read our guide to the best smartphones.
How to activate an eSim
Downloading and activating an eSim is much easier than the days of waiting for a physical Sim card to arrive in the post, and then fiddling around with opening your phone and inserting it. Follow these simple steps to get your eSim ready to go:
- Apple iPhones: Settings > Mobile Data > Add eSim > Scan QR code, then your chosen plan will be downloaded and activated.
- Samsung phones: Settings > Connections > Sim card manager > Add mobile plan > Add using QR code > Scan the QR code and your plan will be activated.
- Google Pixel phones: Settings > Network and Internet > Mobile Network > Operator > Add Operator > Don’t have a Sim card? > Next > Scan QR code > Start and your eSim will be activated.
If you didn’t receive a QR code, or scanning it didn’t work, there should be an option to manually add the details of your plan.
Are eSims easy to use?
We surveyed 2,027 UK adults in August and September 2025 about their use of eSims and found they are used in a variety of ways; most people are positive about the experience.
A third switched from a physical Sim to an eSim for regular use at home, 26% used it for travel in Europe and 20% for travel outside Europe, while 22% used it to connect a tablet and 17% to connect a smartwatch.
Generally, eSim users found they worked well, with good ratings for reception (73%), ease of setup (72%), value for money (70%), customer service (64%) and ease of topping up (64%).
How do eSims impact battery life?
An eSim does not use more battery than a physical Sim and is designed to try and minimise battery usage when connecting to a network.
Having multiple active (not just stored) eSim profiles at the same time may use more battery as you are connected to multiple networks simultaneously, but this would be the same for dual physical Sims.
In some eSim-only devices, the battery capacity is larger as the space inside the phone that was previously used to hold a Sim card can instead be used to house a bigger battery.
What is the future of eSims?
eSims have been available since 2016, but consumer usage and awareness isn’t particularly strong, but uptake should increase over the coming years. Kandasamy shared his industry insight on why: 'The adoption of eSims by all major device manufacturers, as well as the recent move to only support eSim form on their devices, will be a catalyst for consumers. Starting with flagship phones, this form will be rolled out to all devices and coupled with eSim management platforms, and the return to travel, will increase eSIM adoption as well.'
He continued: 'According to a report by GSMA Intelligence, about 76% of all smartphones will be using eSims by 2030. In the next few years, as more and more devices support eSim, we can see major mobile device markets like India and China also supporting them. This will force operators to make major shifts in their customers' digital experience, procurement, and plan management capabilities. In the near term, we will see more device manufacturers launching eSIM-only devices, as well as dual-form devices.'
Can't decide which mobile network to switch to? Read our guide to the best and worst UK mobile networks, to find how the different providers ranked in our latest survey.
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