Phone Number Porting


The term phone number porting denotes the practice of keeping an existing phone number when migrating to a different telecom service provider. Porting a telephone number allows you to continue to make calls from and receive calls to your phone number.

All Swiss phone service providers allow the porting of phone numbers – both landline and mobile numbers – at no extra charge. Consumers have the right to keep their phone number when migrating to a different service provider, on the condition that all bills from their previous service provider have been paid to date.

This prevents mobile service providers from discouraging consumers from migrating to competitors by forbidding them from keeping their phone number.

Customers with mobile plans must abide by the minimum terms and notice periods set out in their mobile plan agreement. It is possible to switch to a different offer before the agreement expires, but service providers generally charge very high penalty fees for early termination of contracts. In some cases, penalty fees can be as high as several thousand Swiss francs.

Prepaid SIM card users can also port their phone number when they switch service providers. As a general rule, prepaid customers forfeit any remaining prepaid credits when they terminate their prepaid agreement.

How does phone number porting work?

When you migrate to a new telecom provider, you have to clearly inform your new provider that you would like to keep your existing phone number. Your new service provider informs your previous provider, and coordinates a time for the switch. Porting a phone number typically requires several weeks of advance notice. Service providers should inform you about the exact time at which the porting will occur. Your former service provider only deactivates your SIM card after the number has been successfully ported to your new SIM card.

Important: When the porting occurs, you will have to replace the SIM card linked to your previous provider with the new SIM card provided by your new mobile operator.

Up until the year 2000, the first three numbers of a Swiss phone number revealed which mobile network operated the number. Since the implementation of full phone number porting, it is no longer possible to discern which network you are calling simply by looking at the phone number. Make sure you understand the costs charged by your service provider for out-of-network phone calls.

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