Über Number porting (Rufnummermitnahme)

Number porting (German: Rufnummermitnahme) is the consumer right to keep your phone number when you switch from one mobile provider to another. It is mandated by EU regulation and enforced by each member state's national telecoms regulator - Bundesnetzagentur in Germany, RTR in Austria, Ofcom in the UK.

The German rules cap the porting fee that the new provider can charge at EUR 6.82. Most providers absorb this or roll it into the first bill. The maximum end-to-end timeline is 7 working days, with a maximum service interruption of 25 minutes on the day the port executes.

The flow is simple: sign up with the new provider, tick "Rufnummermitnahme" (port my number), provide your old provider's customer number, pick a port date. On port day, your old SIM goes dark and the new SIM picks up your number, typically within minutes. The new provider closes the old contract automatically - you don't cancel separately.

Porting works in all directions: prepaid to contract, contract to prepaid, contract to contract. Numbers can be ported to eSIM just as easily as to a physical SIM. The only valid reason a provider can refuse is if you are not the registered line holder.