Telephone number portability

Telephone number portability refers to the ability to keep your telephone number when change telephone service providers. In Germany, for instance, telephone number portability is regulated by law. The key provisions are defined in paragraph 46 of the Telecommunications Act (TKG). Telephone customers are thereby legally entitled to keep their telephone number when switching providers. Telephone number portability technically involves disconnecting the number from the old connection and registering it to the connection with the new provider. Telephone number porting is typically subject to a charge.

Telephone number portability and the mobile network

Mobile network providers must provide telephone number portability for contract customers as well as for prepaid customers. The subscriber is entitled to request porting his telephone number at any time. The subscriber no longer needs to terminate the contract with the previous provider to do so. When porting the telephone number without terminating the contract, the mobile customer is obligated to continue paying the fees for the old and, if applicable, the new contract with a different provider. A new mobile number can be assigned to the old contract.
Whilst in the past it was possible to identify the carrier by the mobile prefix and the charges may be incurred, this is no longer the case due to the mixed range of numbers portability creates. For this reason there are now network queries which provide the carrier the number is assigned to.

Telephone number portability and the fixed-line network

For the fixed-line telephone network, the subscriber is only entitled to number portability when terminating the contract with a provider. In addition, the local fixed-line number can only be kept when switching providers within the local telephone network. When changing providers also involves switching the local telephone network, this automatically requires a new number from the new local telephone network. Portability also requires both the old and the new provider having identical customer data. To ensure timely porting, the new provider must submit the request to the releasing provider in due time.