📱 Mobile plans2024-06-22
Learn how to transfer your German phone number to a new carrier (Rufnummermitnahme) — step-by-step, with real costs, timelines, and mistakes to avoid.
Moving to a better mobile plan in Germany doesn't mean you have to give up the number your friends, family, and employer already know. The process of keeping your number when switching carriers is called Rufnummermitnahme — and while it sounds complicated, it's actually straightforward once you know the steps. Whether you're switching from Telekom to a budget MVNO or from one prepaid SIM to another, this guide walks you through everything.
Rufnummermitnahme literally means "phone number portability" in German. It's the legal right — guaranteed under German telecommunications law (Telekommunikationsgesetz, TKG) — that allows you to keep your existing mobile number when you switch to a different carrier.
For Moroccans living in Germany, this matters a lot. Your phone number is often tied to:
Losing your number means updating dozens of contacts and services. With Rufnummermitnahme, you avoid that headache entirely — and it costs you nothing extra in most cases.
Good news: all German mobile carriers are legally required to support Rufnummermitnahme. This includes:
It doesn't matter whether you're on a postpaid contract (Vertrag) or a prepaid SIM — you can transfer your number in either direction.
You can only port a German mobile number (starting with +49) between German carriers. If you came from Morocco and want to keep a Moroccan number, that's not possible within the German system. Rufnummermitnahme applies exclusively to numbers already registered in the German national numbering plan.
Here's how the process works in practice:
Before you can move your number, you need a code from your current carrier. This is called the Portierungskennung (also known as the KÜN — Kundenkennungsnummer).
Choose your new plan and sign up. During the registration process, you'll see a field asking whether you want to keep your existing number (usually labeled "Rufnummermitnahme" or "Bestehende Rufnummer mitnehmen").
Here's something many people get wrong: you do not need to separately cancel your old contract. When you initiate a number port, the new carrier sends a transfer request to your old carrier, which simultaneously cancels your old contract or SIM. This is handled automatically under German law.
Exception: If you're on a postpaid contract with a minimum term (Mindestvertragslaufzeit), you may still owe fees until the contract period ends — but the number transfer itself still goes through.
The actual number transfer typically takes:
You'll usually receive an SMS or email from both carriers confirming the transfer date. On that date, your old SIM stops working and your new SIM becomes active with your old number.
Don't throw away your old SIM until the transfer is fully confirmed. On the handover day, there may be a window of 1–2 hours where neither SIM works. Keep your phone nearby and test the new SIM as soon as the switch is supposed to happen.
In most cases, Rufnummermitnahme is free. German law prohibits carriers from charging excessive fees for number portability. However, watch for these potential costs:
| Situation | Typical Cost | |---|---| | Portability code (KÜN) from current carrier | Free (legally required) | | Prepaid-to-prepaid transfer | Free (most carriers) | | Postpaid number transfer | Free at new carrier; early termination fees may apply at old carrier | | Activation fee at new carrier | €0–€29.99 (varies by provider; often waived with online signup) |
For example, WinSIM and PremiumSIM frequently run promotions with 0€ activation and free number porting. Aldi Talk charges no porting fee. Even O2 and Telekom do not charge for receiving a ported number.
Watch out for early termination fees (Vertragsstrafe): If you're locked into a 24-month contract with, say, Vodafone, and you port out after 6 months, you may owe the remaining monthly fees. Always check your contract terms before initiating a port.
Many Moroccans in Germany start with a prepaid SIM (like an Aldi Talk or Lidl Connect card) before committing to a longer contract. Here's what you need to know for prepaid-to-prepaid transfers:
This is where most confusion and frustration happens. Here are the most common mistakes:
Rufnummermitnahme is one of the most consumer-friendly rules in the German telecoms market, and it's something you should use without hesitation when a better plan comes along. The process takes just a few minutes of admin and a few days of waiting — and you walk away with a cheaper plan and the same number everyone already knows.
If you're still in the early stages of your move to Germany and want help navigating SIM cards, Ausbildung applications, or paperwork in general, book a consultation with our German immigration specialist (€16) to plan your move. Our team can help you with everything from your CV builder to your Anschreiben generator so your German journey starts on the right foot.
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