Comparing mobile plans: network, data and SIM-only (2026)
Which network, how many GB, SIM-only or phone included — and how number portability keeps you flexible. The complete guide to the right mobile plan.
The network decides — check it first
The cheapest plan is useless if the network is weak at home or on your commute. Germany has three large networks — Telekom, Vodafone and O₂ (Telefónica) — and 1&1 is building its own as a fourth operator.
Many cheap brands (discounter plans) run on one of these networks. So focus less on the brand name and more on which network is behind it — and check coverage for your postal code on the provider’s map.
Ask neighbours or colleagues which network works best locally. Real experience at your address often says more than any advertising.
Estimate data volume realistically
Data volume is the biggest price driver. If you mainly use messaging, mail and navigation, a few gigabytes often suffice. If you stream a lot of video on the go or use your phone as a hotspot, you need much more.
Mind what happens after you use it up: most plans throttle speed heavily instead of charging extra. That protects against nasty surprises but is useless for streaming once the volume is gone early.
5G is included in many plans, but sometimes for a surcharge or at limited speed. For most people, solid LTE (4G) with enough volume is perfectly fine.
SIM-only or phone with contract?
SIM-only means: just the plan, no new device. This is usually the cheapest and most flexible option if your phone still works well.
With a bundle (plan plus smartphone in instalments) you pay off the device through the monthly fee. Calculate total cost over the term and compare with SIM-only plus buying a device separately — separating the two is often cheaper and keeps you more flexible.
A bundle ties you to a plan longer. If you like to compare and switch yearly, SIM-only plus your own device purchase usually works out better.
Term, cancellation and prepaid
After the minimum term, contracts may no longer auto-renew for a year — they become cancellable monthly with one month’s notice. Still mind the initial commitment (often 24 months).
Prepaid is maximum flexibility without a contract: you top up and pay only for what you use. Ideal for low usage, fluctuating needs or cost control — but often more expensive per gigabyte than a contract.
EU roaming is usually included in regular plans at no surcharge. Outside the EU (e.g. Switzerland, Turkey, USA) high costs can arise — check roaming options before travelling.
Switching with number portability
You can take your mobile number to the new provider — that is your right. The fee for this is capped by law at only a few euros; many providers even refund it as a switching bonus.
Arrange portability in good time: you can usually request it shortly before or after the contract ends so there is no gap and you do not lose your number.
Modern plans often offer an eSIM instead of a physical card — handy for dual-SIM phones and for a fast switch, without waiting for the SIM to arrive by post.
Practical tips
- Check network coverage for your postal code first — before the price.
- Choose data volume by real usage, not by the biggest offer.
- Compare SIM-only plus a separate device purchase against the bundle — often cheaper.
- Request number portability in good time to avoid a gap.
- Look for switching bonuses that refund the portability fee.
Common mistakes to avoid
- Booking the cheapest plan without checking local network coverage.
- Paying for far too much data that is never used.
- Signing a bundle without comparing total cost against SIM-only.
- Travelling outside the EU without a roaming check and risking high fees.
- Forgetting number portability and losing your old number.
Checklist before you compare
- Network coverage checked for home and work.
- Required data volume determined by real usage.
- Decided: SIM-only or bundle (with total cost calculation).
- Term and notice period checked.
- Roaming needs for travel outside the EU clarified.
- Number portability prepared.
Frequently asked questions
Which network is best?
It depends on where you live. Telekom often has the widest coverage; Vodafone and O₂ are strong regionally. Check the network map for your postal code.
How many GB do I need?
A few GB suffice for messaging and navigation. If you stream a lot on the go or use your phone as a hotspot, choose much more.
Is a phone with contract worth it?
Only if the total cost over the term is lower than SIM-only plus buying a device separately. Separating the two is often cheaper.
Can I keep my number?
Yes. Number portability is your right; the fee is legally capped at a few euros and is often refunded as a bonus.
Is prepaid or contract better?
Prepaid is flexible and without commitment but often more expensive per GB. A contract pays off with regularly high usage.
Compare matching plans
What we compare for you:
- Data volume
- Network
- Term
- 5G
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