E.164 is the international telephone numbering standard established by the International Telecommunication Union (ITU-T).
A Mobile Station International Subscriber Directory Number (MSISDN) is the telephone number assigned to a mobile subscriber for voice calls and messaging services.
An MSISDN is the number people use to call or message a mobile device. Mobile operators use MSISDNs to identify subscriber services and support voice, SMS, MMS, and other mobile communications.
Examples of MSISDNs may include mobile numbers such as:
An MSISDN is associated with a subscriber service, but it is not the only identifier used within a mobile network.
MSISDNs are typically formatted according to the E.164 ( link to page) international numbering standard.
An MSISDN contains:
Example: +1 858 555 1234
Components:
Because MSISDNs commonly follow E.164 formatting, the terms are often confused.
E.164 defines the numbering format, while an MSISDN refers to the actual mobile subscriber number assigned to a user.
MSISDNs are used throughout mobile communications networks to identify subscribers and deliver voice and messaging services.
Communications providers, enterprises, and application platforms use MSISDNs for customer onboarding, authentication, messaging, and contact management workflows.
Because MSISDNs are associated with subscriber services, they are frequently referenced in number validation, routing, and identity-related processes.
Related topics include:
When a mobile subscriber places or receives a call, the MSISDN serves as the public-facing telephone number associated with the service.
The MSISDN is the number shared with individuals, businesses, applications, and communications platforms.
Mobile operators use MSISDNs to support:
Routing systems may reference additional databases and network records to determine how communications should be delivered.
MSISDNs are associated with subscriber records maintained by mobile operators.
These records support:
MSISDNs allow callers to reach mobile subscribers using a dialable telephone number.
SMS and MMS messages are addressed using MSISDNs.
Messaging platforms use MSISDNs to identify message recipients and support SMS and MMS delivery.
Many organizations use phone numbers as customer identifiers for:
In these scenarios, the MSISDN serves as the primary phone number associated with a customer account.
MSISDNs are commonly used in:
Organizations frequently validate MSISDNs before initiating communications or authentication workflows.
MSISDN stands for Mobile Station International Subscriber Directory Number.
In most cases, yes. An MSISDN is the dialable telephone number assigned to a mobile subscriber.
E.164 is the international numbering standard that defines phone number formatting. An MSISDN is the actual mobile phone number assigned to a subscriber.
An MSISDN is the public-facing phone number used for calls and messaging. An IMSI is a network identifier used for subscriber authentication and network operations.
Yes. A subscriber or organization may be assigned multiple MSISDNs depending on services, devices, or business requirements.
MSISDNs support voice communications, messaging, customer identity workflows, authentication processes, and mobile service delivery.
MSISDN validation helps organizations confirm that a mobile number is properly structured and suitable for communications workflows. Additional intelligence may be required to determine reachability, service status, or current routing information.