IMSI and Multi IMSI: the differences and advantages

What is an IMSI?

An International Mobile Subscriber Identity (IMSI) is a unique number, typically 15 digits long, that is part of the Subscriber Identity Module (SIM). SIM cards are identified based on their IMSI.

How is this set of digits divided?

• The first 3 digits represent the Mobile Country Code (MCC).
• The next 2-3 digits represent the Mobile Network Code (MNC), which identifies the operator.
• The remaining 9-10 digits uniquely identify the subscriber within a particular network. Some MNOs use the first two digits to indicate the home location register.

Typically, the IMSI is available in the SIM management system of your IoT connectivity solution. However, the exact format of the IMSI can vary between MNOs. When a device wants to access a network, it sends the IMSI.

What is a multi IMSI?

Multi IMSI technology enables one SIM card to store multiple IMSIs, allowing the device to switch between different providers without the need to replace the physical SIM card. This is a smart and cost-effective solution for devices deployed internationally or operating in multiple countries, as it allows them to use local tariffs and avoid high roaming costs.

What is the biggest difference?

A traditional SIM card stores only one IMSI, which means you are dependent on one network and may face high roaming charges. In contrast, a multi IMSI SIM card can store multiple IMSIs. Through OTA (over-the-air) updates, you can switch between different IMSIs, thereby avoiding high roaming charges.

More information

For more information on IMSI and Multi IMSI, please contact us at +31-85-0443500 or by email at info@thingsdata.com.