What is an eSIM and how does it work?

An eSIM is the latest generation of SIM cards. And because it’s digital, there’s no need to mess around swapping fiddly bits of plastic when you want to change networks or snap up cheaper roaming deal overseas.

If you’re looking for a new deal, check out our best SIM only plans. Or, if you need a new handset, check out our best mobile phone deals.

What is an eSIM?

An eSIM is an electronic or virtual version of the traditional SIM card.

Unlike the tiny plastic version you slot in your phone, an eSIM comes in the form of a tiny microchip that’s built into your phone, so you can’t take it out.

If your phone has an eSIM, it can be used across certain networks and plans.

Unlike traditional SIM cards, where you can only use one at a time, with eSIMs, you can have multiple plans and even phone numbers at the same time. This can save the hassle of having two different phones for work and home, as well ensuring you don’t have to mess about with plastic SIM cards when switching deals.

While eSIMs themselves have been around for a few years, it tends to be the newer more pricey UK handsets, produced over the last few years, that come with an eSIM option.

What are the advantages of an eSIM?

The big advantage of having a digital eSIM is the extra flexibility it offers. It makes it quicker and easier to switch network providers and plans without the need to get hold of and swap over physical SIM cards.

Instead of having to go through the process of getting a new SIM card, and applying for a PAC code (Porting Authorisation Code) to keep your number, with an eSIM, you can more easily switch between providers and plans.

Another, and potentially big advantage, with eSIMs, (depending on your lifestyle), is that it gives you the option of having more than one number on the same handset.

You could for example, have one number attached to your eSIM and another with your traditional SIM card.

This means if you have separate phone numbers for work and home, you can manage both on the same handset.

Depending on where you live and work, you may find certain networks have better coverage across different areas. And you can switch between plans using an eSIM to take advantage of this.

When going abroad, eSIMs can make it easier to use a local SIM and thereby save money on your mobile bill with cheaper rates. You might well be able to find a better deal than any bolt-on travel option from your existing provider.

Are there any disadvantages of an eSIM?

You can’t pull out an eSIM in the same way you would with a physical SIM card.

While this may not seem a big problem, it’s worth being aware that you could find yourself minus a SIM, in the event you lose your phone or it breaks and you want to use an older spare handset that doesn’t support eSIMs.

Another disadvantage is that you can’t currently use eSIMs across all UK networks and some older mobile devices may not be designed for use with eSIMs.

Which phones support eSIMs?

Not all phones are compatible with eSIMs. However, as a general rule, newer UK smartphones, released over the past few years should be eSIM compatible.

Most Google Pixels and Apple iPhones produced since 2018 onwards support eSIMs as well as most Samsung handsets from 2020 onwards.

The easiest way to find out if your mobile supports eSIM is by looking up the make and model of your phone on the manufacturer’s website.

Which networks support eSIMs?

Although not all UK networks currently support the use of eSIMs, Vodafone, Three, EE and O2 provide eSIMs with compatible handsets, along with smaller providers, like Lyca Mobile.

In most cases, with these providers, you can use eSIMs on pay monthly deals and a pay as you go deal with Lyca Mobile.

Do I need an eSIM?

If you’re buying a new phone and going for a more top-end model, chances are your new phone may already come with an inbuilt eSIM.

While you can’t take it out, you don’t have to use it and can use your phone in the usual way by inserting a traditional SIM card.

If, however, you like the option of being able to switch plans because you regularly work or travel overseas, or want the option of multiple numbers and plans on your handset, it may be worth making sure your next mobile has an eSIM.

Do eSIMs help with roaming?

One big bonus of having a mobile with an eSIM is that it can make it easier to switch plans to take advantage of cheaper call and data deals when you’re overseas.

This is because you can store more than one plan on your eSIM, although you can only use one at any time.

In reality, this means if you want to make calls and send emails while waiting in a UK airport lounge, you can do so, before seamlessly switching to a local plan once you land on the other side of the world.

While within Europe, some providers have re-introduced roaming charges across Europe, some still offer the option to use your existing package of calls, texts and data at no extra cost. So in this case, switching to an eSIM, especially for a short European city break, may not be worth it.

However, with long haul destinations, where overseas call and data costs can be eye wateringly high, and even international ‘bolt on’ options from your existing provider can be costly, you could benefit from switching to a local eSIM deal to save money.

What’s the difference between a nano SIM and an eSIM?

A nano SIM is the latest and smallest version of traditional SIM cards, after the standard and micro versions. It’s a tiny physical SIM card that you insert into your phone, whereas an eSIM is a chip installed in your phone that you can’t take out.

On the plus side, with a nano SIM, you can switch phones, whereas with an eSIM, it’s only on one device.

However, if you want to quickly switch between networks, say when travelling, it may still be quicker and easier, not to mention cheaper, to use an eSIM.

Will all phones have eSIMs in the future?

The latest models from Apple, Samsung and Google already come with an inbuilt eSIM option and newer phones from other providers may in time also do this.

While all UK handsets, regardless of whether they have an eSIM option or not, still have a tray option for a traditional SIM card, some of the newer phones within the US no longer have this.

In the US, the iPhone 14 only has an eSIM option, as the handset doesn’t come with a physical SIM tray.

Over time, this could mean we see an end to the traditional SIM tray option, especially as time goes on, more providers are likely to offer eSIM plans and deals.

Do I have to get an eSIM?

UK smartphones come with traditional SIM trays. So even if you have the option for an eSIM, you don’t have to use it.

You don’t have to rush out and buy a new phone with an eSIM, it’s all about choice. However, having both can bring some advantages. Using both your eSIM and a physical SIM card means you can set up your phone to work across multiple numbers, say for both home and work, instead of switching between two handsets, which can be cumbersome.

Is an eSIM right for me?

Whether you choose to use your eSIM or a traditional physical SIM card is up to you. In a nutshell, if you work or travel abroad a lot, then having and using an eSIM could help you save money with cheaper local calling plans.

And if you tend to use different mobiles for work and home, then an eSIM can make life easier with the option to use multiple numbers from the same phone.