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Request a Carrier Selection Code (CSC)

Service description

Request a Carrier Selection Code (CSC) to give your customers a free choice of carrier for national and international calls irrespective of their access network provider. 

CSC are five-digit short numbers. They are used exclusively as a prefix to identify the telecommunications service provider to which they are allocated.  By dialling a specific CSC before a telephone number, customers can select the holder of that CSC as the carrier for that particular call. 

Please note the following when ordering a CSC:

The number of available CSC is limited. You will only be issued multiple CSC if you can demonstrate as a telecommunications service provider that the resulting possible uses are distributed between the different CSC.

Do you have any questions or comments about the 'Request a Carrier Selection Code (CSC)' service?

Contact us using the service Contact for questions about telecom services.

Support - Contact

Federal Office of Communications
Zukunftstrasse 44
Postfach 256
CH-2501 Biel/Bienne

Tel.: +41 58 460 56 41
Contact form