How to switch from SIM to eSIM?
Switching from SIM to eSIM means replacing your carrier's physical card with a digital profile stored on your phone. The process has three steps: confirm your device is compatible, request the change from your carrier, and scan the QR code they send you to activate it. You don't need to buy anything new.
The word "eSIM" comes from "embedded SIM," meaning a SIM integrated into the phone itself instead of a card that is inserted and removed. Instead of a piece of plastic with a chip, you have a digital file with the same information: the number, plan, and data that identify you to your carrier's network. For most people, this change goes completely unnoticed: the phone still works the same, calls still come in, and the data plan remains the same. The only thing that changes is where that information resides within the device.
The rest of this article explains each step calmly, what you need before you start, what errors to avoid, and what happens to your eSIM when you travel, because that's where this concept becomes truly useful.
What is an eSIM and how does it differ from a physical SIM?
Think of a physical SIM as a plastic key you give to your phone: if you lose it or move it to another device, you have to physically move the piece. An eSIM is that same key, but stored as code inside the phone. There's nothing to insert or that can fall out when you open the tray with a clip.
Functionally, both do the same thing: they identify you to your carrier's network so you can make calls, send messages, and use data. The difference lies in how they are installed and in some practical advantages of the digital version.
| Feature | Physical SIM | eSIM |
|---|---|---|
| How it is installed | A physical card is inserted into the phone's tray | Activated by scanning a QR code or with a link from the carrier |
| Can it be lost or damaged? | Yes, it is a physical piece | No, it is a digital profile within the device |
| Changing phones | You remove the card and insert it into the other device | You ask the carrier to reassign the profile to the new device |
| Multiple profiles at once | Only if the phone has a dual physical tray | Many devices allow storing multiple eSIM profiles and using one or combining it with a physical SIM |
| Availability | Practically all phones and carriers | Only recent devices and carriers that already support it |
To understand the concept in more detail, you can review this guide on what an eSIM is, or if you're still unsure which one is best for you, this comparison between SIM and eSIM will help you decide based on your situation.
What do I need to switch my SIM to eSIM?
Before requesting the change from your carrier, it's a good idea to check three things so the process doesn't get stuck halfway.
- An eSIM-compatible phone. Not all devices have this feature, and some have it but with restrictions depending on the country where they were purchased. It's best to check the exact model before starting.
- The device must be unlocked. If your phone is still tied to a specific carrier by a financing plan, you may not be able to activate an eSIM from another provider until it's unlocked.
- A stable Wi-Fi or data connection. Activation is done by downloading the profile from the internet, so you need a reliable network when scanning the QR code.
- Your account number or the data requested by the carrier to confirm you are the line holder before authorizing the change.
If you're not sure if your device supports eSIM, this list of eSIM-compatible phones will clear up any doubts before you request the change.
How to request the change from your carrier step by step
The exact procedure varies by carrier and country, but in practice, almost all follow this same sequence:
- Go to your carrier's app or website (or go to a physical store if you prefer to do it in person).
- Look for the "switch to eSIM" or "manage my SIM" option. It is usually found within the line settings section.
- Confirm your identity with the requested data: account number, verification code, or a security question.
- Request the change. The carrier generates a unique QR code, which usually arrives by email, within the same app, or is displayed on screen in the store.
- Scan the code from your phone to download and install the new eSIM profile (the next section explains this step in detail).
Before scanning anything, confirm with your carrier if the change will immediately deactivate your physical SIM or if it will coexist with the eSIM for a while. This difference prevents you from losing signal in the middle of the process if something doesn't go right the first time.
If the device you want to use appears as incompatible or the carrier does not yet offer eSIM in your country, you will continue to use the physical SIM without any problem: it is not a requirement, it is an alternative.
How can I transfer my number from SIM to eSIM without losing it?
Your phone number doesn't live on the SIM card or the eSIM profile: it lives in your carrier's systems, associated with your account. Therefore, when you switch from a physical SIM to an eSIM with the same carrier, the number is automatically maintained, because you are not moving it to another company, you are just changing the card's format.
The only situation where your number might be affected is if, in addition to switching to eSIM, you also change carriers (which in many countries is called number portability). In that case, the number portability process is separate from the eSIM activation process, and usually the new carrier guides you through both at the same time. If you only stick with the same carrier and change the card format, there is no portability involved: it's a simple technical replacement.
How to activate the eSIM profile on your phone
Once the carrier provides you with the QR code, activation is done from the phone itself, without additional apps.
- Go to your phone's settings, in the mobile network or cellular data section.
- Look for the "add eSIM" or "add cellular plan" option.
- Select scan QR code and point the camera at the code sent by your carrier.
- Confirm the installation and wait for the device to download the profile (it usually only takes a few seconds with a good connection).
- Assign a label to the line (for example, "personal" or "work") if the phone asks you, especially if you plan to keep more than one active profile.
One detail almost no one mentions: an eSIM QR code works only once. If you accidentally scan it on the wrong device, you won't be able to reuse it on the correct one; you'll have to ask the carrier to generate a new one. That's why it's a good idea to have the correct phone handy before opening the camera, instead of trying it "to see if it works" on the closest one.
If you want the procedure with screenshots for different operating systems, this guide on how to install an eSIM covers it step by step.
Common errors when switching from SIM to eSIM
Most problems when making this change do not come from the technology itself, but from skipping one of the previous steps. These are the most common:
- Scanning the QR without stable Wi-Fi. If the connection is lost halfway through the download, the profile may be partially installed and a new one will need to be requested.
- Not verifying that the device is unlocked. A phone still tied to a financing plan may reject an eSIM profile from another carrier.
- Saving the QR as an image and re-sending it. Since the code is single-use, re-sending it to another device or trying to reuse it will not work; you must request a new one directly from the carrier.
- Deactivating the physical SIM before confirming that the eSIM is active. It's best to wait until the new line is working (with signal and data) before getting rid of any backup.
If something didn't work as expected, this guide to common eSIM problems reviews the most frequent causes and how to solve them without having to call your carrier.
What happens to your eSIM when you travel abroad?
This is where it's worth pausing, because many people think that "SIM to eSIM" is only important if they change carriers in their own country, and in reality this same concept solves a different problem: that of running out of data (or paying too much) when you travel.
Imagine Sofia, who lives in Guadalajara and is going to spend ten days in Buenos Aires visiting her family. If she only had her Mexican physical SIM, she would have two uncomfortable options: activate her carrier's international roaming (which tends to be expensive and with unclear data limits) or buy a local SIM card as soon as she lands, which involves finding a store, waiting in line, and losing her Mexican number while using the Argentine line.
With an eSIM, the situation changes completely. Sofia can keep her Mexican line active (to receive calls and messages with her usual number) and, at the same time, install a second data-only eSIM before traveling, without touching her physical card or having to find Wi-Fi when she arrives at the airport. Both profiles coexist on the same phone: one for her usual identity, the other for browsing with local data in Argentina at a cost designed for travelers, not residents.
This is exactly what a data eSIM for travel like PuraSIM's solves: it's purchased and activated before the flight (activation takes approximately 1 minute once you have Wi-Fi), and it's ready to use as soon as you land, without having to find a physical store in a country you don't know. You can buy it up to 180 days in advance and activate it when you need it within that period. And if something doesn't go as expected during your trip, there's 24/7 support in all languages via email and WhatsApp, without needing an international call.
To better understand why traditional roaming is usually more expensive than a travel eSIM, this comparison between eSIM and roaming explains it with examples.
Local eSIM vs. data eSIM for travel: which to use and when
Although both are called "eSIM" and are activated in a similar way, they address different needs. It's easy to confuse them, so it's good to have them clear side by side.
| eSIM from your local carrier | Data eSIM for travel | |
|---|---|---|
| What it's for | Replaces your usual physical SIM, with your number, calls, and messages | Provides mobile data at your destination, without an associated voice number |
| Keeps your usual number | Yes, it's your same line in a different format | Not applicable: it's an additional data-only line |
| Where to contract it | With your current carrier, in your country | Before traveling, online, selectable by destination |
| When it's convenient | When you want to stop using a physical card in your daily life | When you're traveling and need data without relying on roaming |
| Coexists with your physical SIM | It replaces it (although some devices allow both) | Yes, it's used alongside your usual SIM or eSIM as a separate data line |
If you're clear that your next trip is why you're interested in this topic, further down in this article we provide a direct link to the available plans by destination, with coverage in over 200 destinations.
Frequently asked questions
Does switching from SIM to eSIM have any cost?
It depends on the carrier: each has its own policy for changing formats in your country. Before starting the process, confirm it directly with your carrier to avoid surprises on your next bill.
Can I have both a physical SIM and an eSIM active at the same time?
On many recent phones, yes. You can keep your physical SIM for your usual line and add an additional eSIM profile, for example, a data line for when you travel, without having to choose between one or the other.
What happens to my eSIM if I change phones?
The eSIM profile does not automatically transfer when you change devices, unlike moving a physical card. You need to ask your carrier to reassign or regenerate the profile for the new phone.
Do I lose my contacts or WhatsApp when I switch from SIM to eSIM?
No, your contacts and apps do not depend on the type of card, but on your phone's memory or your cloud account. Even so, it's good practice to have a backup before any network configuration changes.
Does eSIM work the same as a physical SIM for calls and messages?
Yes, when it's an eSIM from your local carrier that replaces your usual line, it works exactly the same for calls, messages, and data. A data eSIM for travel, however, is usually data-only, without a voice number.
Do I need Wi-Fi to activate my eSIM?
Yes, you need an internet connection (Wi-Fi or data) when scanning the QR code, because the profile is downloaded from the carrier's servers during activation.
What if my phone isn't compatible with eSIM?
You simply continue to use your physical SIM without any problem: it is not mandatory to switch to eSIM. If you travel and your device does not support eSIM, the alternative is still your carrier's roaming or a local physical SIM at your destination.
Conclusion
Switching from SIM to eSIM is, at its core, a format change: the same line, the same number, but stored as a digital profile instead of a physical card. The process is handled by your local carrier, and once you understand the steps (check compatibility, request the QR, and activate it with Wi-Fi), there's no major complication.
Where this concept really changes the way you travel is when you combine it with a separate data eSIM for your trips abroad: you keep your usual number and, at the same time, have data ready to use as soon as you land, without relying on roaming or finding a store in a country you don't know. If your next trip is coming up, you can start by checking out the definitive guide to traveling with eSIM and then choose your plan from the international eSIM collection based on your destination.
