March 1, 2023
What Is An eSIM And How Do I Get One? - Your Guide to eSIMs

What Is An eSIM And How Do I Get One? - Your Guide to eSIMs

Read time:
4 Minutes

As technology develops, many smartphone manufacturers are changing to eSIMs, an alternative to traditional, physical SIM cards. 

We’ve been supplying SIM cards to our customers for years, and we’re finding it increasingly common that our clients are asking for eSIMs for their devices—particularly devices that they switch between work and personal.

But what are eSIMs? How do they work and do they actually have any benefits over traditional SIM cards?

What is an eSIM?

eSIM stands for embedded SIM, and is a small microchip inside your smartphone or tablet that acts as a SIM card, rather than having a physical, removable SIM card in a tray.

Evolution of a SIM Card. From Mini SIM to ESIM
The Evolution of the SIM Card—From Mini SIM to eSIM

eSIMs are a direct replacement for existing, physical SIM cards, meaning that you won’t have to have a physical sim at all. Instead, you just use the embedded microchip inside your device for call, SMS and data communications.

ESIMs are completely re-programmable. This means that you can change them to a different provider if required. Just like regular SIMs, your network provider can also upgrade or change tariffs remotely, without the need to reprogram your eSIM.

eSIMs are becoming increasingly common in new phones, and it’s clear we’re on a trend towards phone manufacturers phasing out the physical SIM card all together. More and more of our customers are specifically requesting phones with ESIM capabilities.

Apple, Samsung, Huawei and Google have all embraced the eSIM, with most of their newly released devices having full eSIM support. Some of these manufacturers even have multiple eSIMs inside their device—and Apple have totally replaced the physical SIM with eSIM in all their latest iPhones in the US.

How does an eSIM work?

At its core, an eSIM works in much the same way as a physical SIM card. It allows your device to connect to a mobile network such as EE, O2, Vodafone etc. Each eSIM is connected to a tariff, and when activated, your eSIM gives your device network access for calls, SMS, data and other services.

Your eSIM contains unique identifiers called an IMSI (International Mobile Subscriber Identity). The IMSI is totally unique to each SIM, and your device uses the eSIMs IMSI to connect to the network.

Diagram of an ESIM
eSIM Diagram

Effectively, your device creates a handshake with the network, using the eSIMs IMSI as the authenticator to identify your device, tariff and data package. This is very similar to how a normal SIM works—except a normal SIM cannot switch between different networks, or be reprogrammed. 

How do you setup an eSIM?

Every device has a slightly different process for setting up an eSIM, but in general, it’s a similar process. With most phones, you can setup in a matter of minutes by following the on screen instructions.

Learn how to setup an eSIM on your iPhone here. Learn how to setup an eSIM on your Android here.

eSIMs are usually setup by scanning a QR code, which is provided to you from the network (if you’re a customer of Bytes Digital, we’ll send you your eSIM QR code). If you have an existing physical SIM, some providers allow you to convert that into an ESIM on your device.

Transferring an eSIM

If you already have an eSIM, and want to move it to a new phone, you can simply follow the setup instructions, but choose ‘transfer’ rather than ‘setup new eSIM’. This allows you to port your SIM over to your new phone.

This process can vary from device-to-device, so follow your device specific instructions to ensure the eSIM correctly ports over.

Benefits of an eSIM

Using an eSIM has lots of benefits, from increasing the waterproof-ness of your device, to allowing you to more easily choose between data packages. Here’s a list of the top benefits of an eSIM…

1. Dual SIM

With more and more people moving to mobile and flexible working, dual SIMs are becoming increasingly common. To keep rollout costs to a minimum, employers are choosing to provide their teams with a single phone, capable of supporting both a personal and business SIM.

Using an eSIM, you can quickly and easily setup a secondary SIM card in one device. Most phones allow you to tag each of your numbers, so you have full visibility when switching between the two. You can even use an eSIM for both mobile numbers if required.

2. Waterproof Phones

Because an eSIM is not removable, it means that phone manufactures don’t need to put a SIM card tray inside the phone. This increases the waterproofing of the phone, as it has fewer gaps and potential openings for water. As we mentioned earlier, Apple have already phased out physical SIM trays in their US iPhones, with more countries expected to join that list soon.

3. Different data packages & networks

Having multiple eSIMs in you to utilise multiple different data tariffs and networks. For example, you could have a Vodafone SIM on a 20GB tariff, and an EE SIM on a 1GB tariff. You could use the Vodafone eSIM as your main data tariff, with EE as a backup.

This is particularly helpful for those in more rural areas, where mobile coverage varies, and staying connected is important. Lots of our customers utilise an eSIM to give them multi-network capabilities. If they’re in a Vodafone blackspot, for example, they could switch to EE.

4. Easy international roaming

eSIMS are great for frequent international travellers. When travelling, roaming data can be very expensive, and so can international bolt-ons. Many frequent flyers have multiple SIM cards when travelling, each from their own native country. With eSIMs, you can quickly switch between mobile networks, without needing to physically change over a SIM.

For example, if you landed in Singapore, and needed to switch from your UK Vodafone tariff to your Singapore Singtel tariff, you could go into settings and choose Singtel as your network provider to avoid Vodafone’s expensive international roaming charges. You don’t need to carry around multiple SIMs or a SIM ejection tool.

Disadvantages of an eSIM

While eSIMs have many advantages and benefits, they’re not perfect. Here are some drawbacks and disadvantages of using an eSIM…

1. Cannot swap providers easily

With a traditional, physical SIM card, switching providers is simple and easy—you just pop out the old SIM and pop in the new one. However, with an ESIM, this process is a little more involved.

While you can still port your number between different networks using a PAC code; when the the time comes to actually switch, you will need to disable your old eSIM, and setup your new one. This can have added complications if certain contacts are linked to use one of your eSIMs etc.

2. Fewer network options (at the moment)

As it stands, not every mobile network offers eSIMs. While most of the main providers do providing eSIMs, a few of the smaller networks are yet to catch up. This isn’t a problem for most people, but if you utilise a network without eSIM capabilities, then you won’t be able to switch to an eSIM at all—which could be a problem soon, with manufactures moving to eSIM-only devices.

That being said, with manufactures such as Apple and Samsung pushing their phones down the eSIM route, it is very likely that all mobile networks will adopt eSIM functionality to support users on those devices.

eSIMs are the future of mobile communications, and they’re here to stay. Soon, we’ll all be using eSIMs and will think back to a time where the physical SIM card existed as a relic.

If you have any questions, or would like some more information about how Bytes Digital can help your business, email hello@bytesdigital.co.uk give us a call on 03331 301 021.

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