What is an eSIM and why should your IoT project care about it?

Connectivity as a service

Reliable connectivity in an IoT project is critical. Knowing the location, status, and accessing data of any globally deployed devices is critical. But how are these devices connected to the network?

For global projects, it’s generally accepted that roaming cellular connectivity is the best solution. And eSIMs take it to the next level when it comes to flexibility and future-proofing any project.

However, there is some confusion in the market about what exactly an eSIM is, what benefits it offers, and what considerations should be made when implementing a global IoT project.official eSIM logo

The official eSIM logo as defined by the GSMA, an industry organization that represents MNO interests.

What is an eSIM?

In an IoT use case, eSIM refers to the software component and the ability to switch carrier/MNO (mobile network operator) profiles over the air (OTA).

Understandably, the confusion comes from the “e” in eSIM as it refers to the “embedded” nature of the physical SIM card.

In fact, eSIMs come in all physical form factors, from the very classic 2FF or mini SIM card, that is ubiquitous in cell phones and its smaller ‘brothers’, to the MFF2, a solderable chip SIM.

The difference is in the software built into the SIM card itself, whether it supports OTA provisioning or not.

The software aspect, eUICC (embedded Universal Integrated Circuit Card), is the key component that allows a SIM, in any physical form, to access the connected infrastructure and receive a new carrier profile.

One reason for the confusion is the official definition of eSIM for consumer use provided by the GSMA (industry body representing the interests of mobile operators). It talks about chip SIMs and their ability to allow end users to switch between operators.

However, the GSMA documentation on the IoT use case states that the eUICC software component that enables over-the-air provisioning can be built into any form factor.


Advantages of eSIM

Switching carrier profiles over the air is especially important when dealing with devices that are deployed around the world because switching physical SIM cards becomes very expensive and time consuming. Not to mention the inconvenience to the user(s) of the device.

The underlying functionality of being able to switch carriers over the air opens up several advantages such as:

  • Streamlined manufacturing process
  • Resistance to tampering and environment
  • Future-proof protection against network sunsets and price changes
  • Global solution for LTE-M and NB-IoT
  • Solution for permanent roaming restrictions

With the use of eSIM in the manufacturing phase, it becomes irrelevant in which country the device eventually ends up. The manufacturing process becomes more streamlined and less complicated. Once the device is in the deployment country, the most suitable profile can be downloaded, whether the decision is based on local roaming restrictions (e.g. in Brazil) or the price of the profile provider.

Without the need to remove the eSIM from the device, the module can be completely sealed in the manufacturing phase. That way, the product itself can be made more secure against physical tampering by malicious individuals and increase the tolerance against environmental factors like temperature, vibration and humidity.

Telecom companies have been shutting down 2G and 3G networks for some time to free up resources for 5G. This means there is an increased urgency to enable all IoT devices to connect to new network technologies. Because eSIM has a standardized format for this access, the project is future-proofed in case networks are shut down and new technologies emerge, this includes NB -IoT and LTE-M.

With an infrastructure as large as telecommunications requiring constant maintenance and innovation, it is understandable that costs will fluctuate over time. These costs tend to impact every end user, including IoT projects. So if you have the technological capabilities that eSIM offers to move to a carrier profile that provides better pricing, you have a big advantage over the competition.

Another important use case for eSIMs is bypassing roaming restrictions. Countries like Brazil and Canada, to name a few, impose such restrictions for 60-90 days, depending on the country. After that period, the devices are kicked off the network. One way to get around this is to take the device out of the country and connect it to another network. However, it is unreasonable and expensive to transport 10,000 e-scooters or the modules on wind turbines across the border. For such cases, loading a local profile where roaming restrictions don’t apply is the answer and eSIM can easily facilitate this.

Should my project use an eSIM?

Broadly speaking, the eSIM can be used in any IoT project where cellular connectivity is required. Whether it makes sense for any project is another matter.

To assess whether an IoT project would benefit from eSIM, consider the following:

  • Is your IoT project large-scale or do you plan to scale up?
  • Are the devices expected to remain in use for years?
  • Do the devices move within a country and/or across borders with increasing roaming costs?
  • Is your IoT project deployed in multiple countries/regions?
  • Is device connectivity critical and requires fallback options?

If the answer to at least one of the above questions is “yes”, it is worth considering eSIM.


Choosing eSIM for a global IoT project will ensure that devices stay connected for years to come, regardless of where you deploy them, what changes occur in the market in terms of price or technology, and give you the flexibility to stay ahead of the competition.

Libelium works on projects with eSIM thanks to close collaboration with connectivity partners such us 1oT, a carrier-independent cellular connectivity provider for IoT & M2M devices. 1oT provides 1 SIM card for any global IoT deployments, with one invoice, one connectivity management platform and one SIM/eSIM solution.

If eSIM is the solution for your IoT project, contact us to start the first steps.