Fraud Blocker
0333 313 5005|

What is an MSISDN number?

What is an MSISDN number?

MSISDN stands for Mobile Station Integrated Services Digital Network. This is the ‘phone number’ used to identify a device during calls or data sessions. When it comes to an IoT network, the MSISDN is crucial in making sure that the different components are connected securely.

What do the numbers in an MSISDN number mean?

When you call someone using a mobile handset, the recipient needs an identifier so they know it’s you who’s calling them. Without an identifier of some sort, the person has no way of telling who is trying to contact them. This also applies when a device is trying to connect to another device via an IoT network.

The MSISDN number is the part of the SIM that is used to identify the unique subscriber who is connected to a network. They are completely unique to a single SIM profile. SIM cards can only have one IMSI, but they can have multiple SIM profiles.

Not all MSISDN numbers are the same length; this is largely dependant on the number of procedures set by a network’s regulatory body and can change from country to country. They are usually 12 to 15 digits long, but 15 is the maximum. There are three elements that make up a MSISDN number:

  • Country code (CC)
  • Subscriber number (SN)
  • National Destination Code (NDC)

All MSISDN numbers follow the same format:


For example:

44 (CC) + 2468 (NDC) + 123456 (NDC)

In this example, your device’s MSISDN number would be 442468123456.

Explore our M2M & IoT solutions


Since they’re both unique identifiers, you may be wondering what the difference between an MSISDN number and an IMSI number is. To put it simply, an IMSI number is a technical identifier used by the network operator, whereas an MSISDN number is what most people would refer to as ‘the phone number’ for a device.


When it comes to systems with multiple interacting devices, your devices’ MSISDN numbers simplify the identification and differentiation of each individual device, making your IoT deployments easier to manage. MSISDN numbers are globally recognised and used by every country in the world.


Using multiple MSISDN numbers can cause a huge security risk for businesses. It’s important to have a platform or system in place in which you can manage the SIM profiles of all your IoT devices. This is especially important in systems using large amounts of devices. Having an IoT portal, such as NOVA, is a great way to keep track of all your devices, securely.