The eSIM revolution: What it is, how it works, and who offers the best tariffs.

The “e” in eSIM stands for “embedded.” Unlike a traditional SIM card, the eSIM is no longer a physical card that needs to be inserted or swapped. Instead, it’s a chip permanently soldered into the device.

How to activate it:

Think of the eSIM as a small, empty container inside your smartphone, smartwatch, or tablet. To use this container, you need to download a digital “eSIM profile.” This profile contains all the information your device needs to connect to your provider’s mobile network (just like the data on a traditional plastic SIM card).

How to activate it:

Think of the eSIM as a small, empty container inside your smartphone, smartwatch, or tablet. The process is incredibly simple and usually only takes a few minutes:

• Book a plan: You order an eSIM-enabled plan from a mobile provider (online or in a store).
• Receive a QR code: Instead of a plastic card, the provider sends you an activation letter or an email with a QR code.
• Add the eSIM: You go to your smartphone’s mobile network settings (e.g., under “Mobile” > “Add eSIM” or “Add mobile plan”).
• Scan the code: You scan the QR code with your phone’s camera.
• Download the profile: Your device connects to the internet (usually via Wi-Fi) and securely downloads the eSIM profile.
• Activate: You confirm the activation, and your new plan is ready to use within moments.

The biggest advantage: This chip can hold multiple SIM cards. eSIM profiles can be stored simultaneously (e.g., your personal plan, a business plan, and a data plan for vacation). Depending on the device, you can then actively use one or even two plans at the same time (dual SIM).

The technology offers enormous advantages, but also has a few disadvantages that you should be aware of.

Advantages (Pros)

• Immediate availability: No more waiting for the mail. A new plan can often be activated within 5-10 minutes of booking.
• High flexibility: Switching providers is quick and easy.
• Perfect for dual SIM: You can use your phone (even if it only has one physical SIM slot) as a dual SIM device (e.g., 1 physical SIM + 1 eSIM). Newer devices like the iPhone 14/15 (in the US) no longer have a physical SIM card slot and rely entirely on dual eSIM.
• Ideal for travel: You can keep your German SIM active and simply add an inexpensive local data eSIM (e.g., for the US or Asia) for your vacation. No more annoying searches for a SIM card shop at the airport.
• Security: In case of theft, the SIM card cannot simply be removed to take the phone offline. This increases the chance of locating the device.
• Space-saving: The elimination of the SIM card slot saves valuable space inside the device, which manufacturers can use for larger batteries or other technologies.

Disadvantages (Cons)

• Inconvenient device switching: The biggest disadvantage. You can’t simply take the SIM card out of your old phone and put it in your new one. Transferring an eSIM profile requires a digital transfer process. While this is becoming easier (e.g., via special transfer tools from Apple or Samsung), it’s often still more cumbersome than a physical SIM card swap.
• Device compatibility: eSIM isn’t yet supported by all devices, although it’s standard on almost all new flagship smartphones (Apple from iPhone XS/XR onwards, Samsung from the S20 onwards, Google from the Pixel 3 onwards). Cheaper or older models often lack this feature.
• Carrier compatibility: While all major carriers support eSIM, some smaller budget providers are still hesitant to offer the technology.

When choosing the “best” provider, we must distinguish between two categories:

• German mobile network operators: For your main contract (calls, SMS, data) in Germany.
• International travel providers: For data-only plans abroad (or for tourists in Germany).

Category 1: Best eSIM providers for Germany (main contracts)

This is where the market has become established. Almost all major providers in Germany offer their standard plans (contract and often also prepaid) as eSIMs.

For a primary contract in Germany, Telekom, Vodafone, and O2, as well as their secondary brands (such as Congstar), are the most reliable options for eSIM. The choice depends primarily on your requirements for network quality and data volume.

For holidays abroad, specialist providers (such as Airalo for flexibility or Holafly for unlimited data) are almost always cheaper and more practical than roaming options from your German provider.

The quickest way to find this out is directly in your device’s settings:

Apple iPhone:

• Go to “Settings” > “Cellular”.
• Look for the “Add eSIM” or “Add Cellular Plan” option.
• (All models since iPhone XS/XR/SE 2nd Gen. are compatible).

Samsung Galaxy:

• Go to “Settings” > “Connections” > “SIM Management”.
• Look for the “Add eSIM” option.
• (All flagship phones since the S20 series are compatible).

Google Pixel:

• Go to “Settings” > “Network & Internet”.
• Tap the “+” icon next to “Mobile Network”.
• Look for “Download SIM instead?”
• (All models since Pixel 3 are compatible).

The eSIM is no longer a thing of the future, but the established standard for modern devices. It offers unbeatable flexibility – whether for using two numbers on one mobile phone or for easy internet access while on vacation.

While switching to a new device is still a bit more complicated than with the old plastic SIM card, the advantages in everyday use clearly outweigh the inconvenience.