eUICC: What is it and what is it used for?

eUICC is the abbreviation for Embedded Universal Integrated Circuit Card. This is a SIM with a type of electronic profile provided on a SIM chip that can be changed remotely.

Change network operator without SIM swap: This is what eUICC and eUICC SIM are all about.

eUICC is the abbreviation for Embedded Universal Integrated Circuit Card. This refers to a SIM card with an overwritable profile that allows the mobile operator to be changed - without physically replacing the SIM card. In general, the eUICC concept is less about the hardware and more about the management of SIM profiles. The special feature is the software on a SIM card rather than the M2M SIM card itself. This software is what gives the SIM an exchangeable electronic profile in the first place, which is provided on a SIM chip. This SIM profile can be overwritten remotely via air interface (Over the Air, OTA) without having to change the SIM card itself. With an eUICC SIM, a new SIM provider can therefore be used without having to change M2M SIM cards in the end device. To enable SIM profiles to be changed, an eUICC requires a minimum memory of 512 KB.

Standard & Industrial: The different properties of eUICC / SIM cards

In order to meet the different requirements of end devices and machines, SIM formats have been and continue to be constantly developed. To ensure that the SIM cards themselves take up as little space as possible, the size has been significantly reduced, leaving more room for other components if required. Basically, a distinction is made between the SIM card formats mini, micro and nano. There are also embedded SIMs that are soldered directly into the modem as a chip. In addition to the standard version, the different formats are also available as "Industrial SIM". This more robust version is designed, for example, for an extended temperature range and a longer service life.

M2M SIM formats of the wherever SIM
Available SIM Formats
Operating Temperature
Read/write Cycles
Data Retention
Standard M2M SIM

-25°C to +85°C

Read/write Cycles


10 years

Industrial M2M SIM

-40°C to +105°C


10 years at -40°C to +105°C
15 years at -25°C to +85°C

2FF, 3FF, 4FF

2FF, 3FF, MFF2

eUICC vs. eSIM: eUICC is not equal to eSIM

eSIM and eUICC are very often used interchangeably, although they mean two different things. eUICC is - as mentioned at the beginning - the software on a SIM card rather than the SIM card itself. By contrast, eSIM (abbreviation for embedded SIM) refers to a different hardware form of (M2M) SIM card. In fact, it is possible that eUICC is offered in the form of an eSIM. In this case, the SIM profile on the eSIM can be changed.

This changeability is particularly interesting for eSIM cards: while the "classic" SIM card comes as a plastic carrier that still has to be inserted into an end device, the eSIM is just a chip. Measuring around 5 x 6 millimetres, it completely dispenses with the plastic carrier and is usually soldered into the device during production. It is therefore no longer necessary to insert a SIM card into an end device - however, replacing the M2M SIM card is much more complicated than using a SIM card slot. With an eSIM, the data for using the mobile network is then uploaded via an electronic profile, for example via Bluetooth.

The advantages of the eSIM over a normal M2M SIM card are its space-saving size, its consistent format and the fact that it does not use plastic as a carrier material, which saves resources. In addition, it cannot slip due to its fixed installation - an important point for IoT devices that are often or always on the move, such as e-bikes. The connection could be interrupted if the inserted SIM card slips. Deliberate theft of the SIM card by an unauthorized person is also ruled out - theft and misuse of an eSIM are not possible.

The advantages and disadvantages of eUICC

The general idea behind eUICC is to increase flexibility for end users with regard to the use of SIM profiles. In theory, it should be possible to change the SIM profile remotely if necessary without having to replace the SIM card itself. As a rule, profiles are changed via an air interface or so-called over-the-air updates (OTA).

This change option would give the user more flexibility, especially in the case of permanently installed eSIM cards, where physically replacing the IoT SIM card is costly and complex. However, even with M2M SIM cards that are not permanently installed, physically replacing the SIM card can involve a great deal of effort. This is particularly true if the SIMs are used in devices at different locations. In this case, the devices would first have to be collected or brought to a central warehouse, or someone would have to travel to different locations to swap the cards on site. In both cases, the effort and costs are high. SIM replacement would only be more complicated with soldered-in SIM cards - in the worst case, no physical replacement is possible at all. In addition to greater flexibility, eUICC also offers a wider range of features, such as a larger memory capacity, than the "normal" UICC.

But as is so often the case, there is a catch: changing SIM profiles is expensive. Very expensive. Not only are the eUICC-capable SIM cards required, whose acquisition costs are higher than those of non-eUICC-capable IoT SIMs, but a platform is also needed to carry out a change, as the service profile and the associated rules and controls must be integrated into a new MNO structure. In addition, different SIM profiles need to be purchased and kept available to switch to. Overall, this can quickly result in high five-figure investment costs.

The investment should therefore be well thought out and usually only makes sense if it is clear that a profile change is to be made via OTA or that it will not be possible to physically swap the IoT SIM cards. The easiest way to use this technology would be to choose a multi-IMSI SIM card.