What is eSIM? And how does it work?

Privacy news
5 mins
An eSIM embedded into a phone.

Apple recently launched its new iPhone 14 series. One feature that stands out on its U.S. models is its exclusive use of eSIM—so no more physical SIM card tray. That’s right, Apple’s decided no more swapping in and out a tiny gold card. No more losing it when you travel. No more hunting for a paperclip to eject it.

Instead, you get eSIM, permanently buried somewhere in your phone. So is eSIM better? And should you use it? Here’s what you need to know.

Read more: Ultimate guide to mobile security for iPhone and Android devices

Types of SIM cards

A SIM (Subscriber Identity Module) card is used to identify you to the mobile network you’ve registered with, allowing you to make calls and send SMS messages.

SIM cards have traditionally existed as physical cards that are removable and transferable to other phones. This means if you have a new phone, you can simply remove it from the SIM card tray of your current phone and insert it into the new phone. All your information stored on the SIM card, such as your phone number, text messages, and phone contacts, will move over to the new phone. But if you want to change to a different mobile network, you’ll have to get a new SIM card.

There are mainly three types of physical SIM cards. They are standard SIM, micro SIM, and nano SIM—each one smaller than the next. In recent years, eSIM has emerged as a new form of SIM card.

What is an eSIM card?

eSIM stands for embedded SIM. It’s a SIM card embedded directly into the motherboard of your device. You can’t remove it and put it in another device.

An eSIM has the same functionality as a regular SIM card. The difference is that an eSIM is rewritable or programmable. This means you can change your network operator without swapping anything out. Everything is handled electronically on your device.

At the moment, eSIM mostly exists in a dual-SIM setup: A physical SIM card is still required as the primary SIM, while eSIM is supported as the second SIM. However, with iPhone 14, Apple made the jump by excluding a physical SIM card slot in the U.S. market. Only eSIM is supported on these phones.

How does eSIM work?

The steps for using an eSIM are roughly like this:

  1. Order an eSIM plan from a carrier’s website or app.
  2. You’ll receive a QR code and additional information from the carrier, by email or generated on their website/app.
  3. Scan the QR code or enter the information to activate your eSIM.

Which devices support eSIM?

Most phones offer support for eSIM in a dual-SIM setup, where a physical SIM card is still required and the eSIM is used as a secondary SIM. The U.S. variants of iPhone 14 (iPhone 14, iPhone 14 Plus, iPhone 14 Pro, and iPhone 14 Pro Max) support only eSIM, doing away with physical SIM card slots.

That said, you can’t use eSIM everywhere as it’s not supported in certain countries, like China. A separate phone might be required if you use an eSIM-only phone and are traveling to a place where you need to insert a physical SIM into your phone.

Advantages of eSIM

1. Use more than one number on your phone

Want to use one number for work that’s separate from your personal number? You can have multiple numbers and plans on one eSIM. You can easily switch between numbers that you use to make calls. No more fumbling with various SIM cards or, worse, carrying around multiple phones.

2. Makes switching carriers or numbers easier

If you find a better mobile plan and want to switch, traditionally you would need to take out your old SIM card and insert a new one from the network operator. This might require you to go to a physical store to get your new SIM card. With eSIM, you can simply activate a new number or carrier by scanning a QR code. It takes only a couple of minutes to complete the whole process and get connected.

3. Prevents identity theft

If you lose your phone with a physical SIM card in it, someone who finds your phone can pop out your SIM card and use it on their phone. They can make calls and send texts while pretending to be you to commit identity theft, or worse, use your phone number to try to log into your social media or bank accounts to get your personal information. SIM-swapping attacks, in which someone pretending to be you claims they lost their SIM card and ask the carrier to link your number to theirs, are also impossible with eSIM.

Read more: What you should do after losing your phone

4. Protects your phone from damage

Phones that support only eSIM, like iPhone 14, will not have a SIM card slot anymore. This means there is one less opening on the frame of your phone to let in dust and water to damage your phone.

Disadvantages of eSIM

1. More easily tracked by network providers

If you have a phone with a regular SIM card, you can remove it from your phone to be less traceable (There are still other ways to trace you, though! Use a burner phone to increase your anonymity.) If you have an eSIM, your phone will be constantly active on your carrier’s network.

Read more: Go incognito: Avoid surveillance in real life

2. More difficult to transfer your SIM data

Traditionally, if you buy a new phone, you’ll have to move your personal data such as your phone contacts to your new phone. Often all you have to do is pop out the SIM card from your current phone and insert it into your new phone. This will be trickier with an eSIM as you can’t physically move it. You will have to download and retrieve your data from the cloud. The whole process will take longer than just working with a transferable SIM card.

3. More risk in the event of data breaches

For traditional SIM cards, all your SIM data is stored on the card, to which only you have access. With eSIM, your data will be sitting on the backend server managed by your network operator. It’s vulnerable to data breaches or hacks.

FAQ: About eSIM

Is eSIM better?
Is my phone eSIM-compatible?