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CERNphone Users and number types

Authorised Users

All CERN classes of personnel are authorised users of the service except:

  • EXMP (ex-member of personnel), PART (Participant to an experiment),

  • RETP (retired participating in an experiment),

  • RETR (Retired),

  • EXTN (external with CERN guarantor) which code is not RETC (Contributing Retiree including honorary members of personnel),

  • ILOF (Industrial Liaison Officer),

  • SCIE (Scientific activities of pensioners of institutes),

  • STAG (Trainee outside CERN official programs).

Please note that personnel having completed their last day of work cannot migrate to CERNphone. CERN ID is necessary to request a CERNphone number. Authorized users can use the service by requesting and using phone numbers.

Types of Phone Numbers

Two different types of phone numbers can be created: Personal and Shared.

Personal Phone Numbers

Any authorised user (see above) can get a Personal Phone Number. Each user can get at most one Personal Phone Number. An authorised user who has not yet a Personal Phone Number can get one from the Resources Portal.

Instructions on how to migrate to and install CERNphone number (personal and shared) are found here.

A Personal Phone Number is attached to a primary account exclusively.


A Personal Phone Number is deleted when the owner leaves CERN. It is first desactivated after 7 days of the contract being over, then reserved for 6 months, in case the user comes back at CERN in the meantime and would like to get back the previous number. After 6 months, it is completely deleted and can be re-assigned to another user. When the person leaves CERN, the phonebook is automatically updated.


A Personal Phone Number can be used on CERNphone apps. It can benefit from all the service features.

Shared Phone Numbers

Shared phone numbers are exclusively for CERN service purposes. This number type replaces the Service Phone Number and Common Area Phone Number types previously available in Skype for Business. Shared Phone Numbers are used as follows:

  • "virtual" numbers for service teams, on-call piquets and for replacing physical shared office phones via the CERNphone "team call" functionality (see the CERNphone User Portal guide)
  • service phones located at CERN (e.g. control rooms, reception rooms, conference phones, etc).

Important: Shared phone numbers should not be used for personal usage nor be provisioned on personal devices.

A shared phone number can be attached to a primary account or to a service account. Usually, they should be created under a service account so that the responsibility for the number does not need to be transferred when the owner's situation changes.

Instructions on how to migrate to and install CERNphone number (personal and shared) are found here.

Please note that a justification can be requested when creating shared phone numbers.


A shared phone number always has one owner (by default its creator).


Ownership of a Shared Phone Number is re-assigned automatically to the supervisor of the previous owner when the owner's contract is over.


A Shared Phone Number can be used on any client, CERNphone apps as well as (only where justified and once available) hardware IP phones. It can benefit from all the service features.