1&1 vs SIM.de vs winSIM: which German SIM is best in 2026?

1&1 vs SIM.de vs winSIM: which German SIM is best in 2026?

Premium brand · Value sweet-spot · Cheapest entry · Same network underneath

All three brands sit inside the United Internet / Drillisch portfolio and share the 1&1 5G network with Vodafone fallback. 1&1 wins on service depth and intro pricing (€9.99 for 3 months). SIM.de is the value sweet-spot at 40 GB for €8.99/month. winSIM is the cheapest absolute entry at €6/month for 10 GB and frequently runs the steepest promo discounts of the three.

Are 1&1, SIM.de, and winSIM the same company?

One parent · Three brand identities · Same SIM, different packaging

Yes — all three brands are owned by United Internet via its 1&1 Drillisch subsidiary. United Internet acquired Drillisch in 2017 and rolled its discount portfolio under the 1&1 corporate umbrella. The brands operate as differentiated price tiers on identical infrastructure: 1&1 is the consumer-facing premium label, SIM.de and winSIM are the online flanker brands targeting price-sensitive switchers without cannibalising the main brand.

Practically, the three-brand strategy mirrors how Telefónica runs O2, Blau, and AY YILDIZ, or how Telekom uses Congstar and fraenk: premium brand keeps margins, discount brands defend the bottom of the funnel. Same engineering, three price cards.

What does each provider charge?

Entry · Mid · Top tier · Intro pricing · €/GB

The pricing gap is wider than the network gap. winSIM’s €6/month entry undercuts 1&1’s ongoing price by 60%, while SIM.de’s 40 GB tariff at €8.99 delivers the best €/GB across the three. 1&1’s headline €9.99 intro price applies for 3 months only; the on-going rate is the figure to budget against.

Source: 1und1.de, sim.de, winsim.de, BNetzA tariff database, verified May 2026. Promo pricing changes monthly — verify before sign-up.

Two practical observations. 1&1’s intro price masks the real cost: €9.99 for three months then €19.99 averages €17.49 over a 12-month run — nearly double SIM.de’s flat €8.99. winSIM and SIM.de swap leadership monthly via promo codes; check both before checkout.

Which network does each run on?

1&1 5G as primary · Vodafone as host fallback · connect 2025 ranking

All three brands ride the same physical infrastructure: the 1&1 5G standalone network launched mid-2024 as Germany’s fourth mobile carrier, with Vodafone Germany as the national roaming host wherever 1&1’s own towers don’t reach. There is no network difference between a 1&1, SIM.de, or winSIM SIM — the IMSI routes through the same core.

1&1’s own 5G coverage is concentrated around Berlin, Hamburg, Munich, Frankfurt, Cologne, and Stuttgart, following the company’s glass-fibre backbone. By early 2026 nationwide 5G coverage reached roughly 95% of the population; urban cores hit standalone 5G speeds up to 300 Mbit/s, while rural areas fall back to Vodafone’s 4G layer transparently. connect’s 2025 network test placed 1&1 fourth of four MNOs, the gap largest in rural voice and indoor reception.

• Cities (Berlin, Hamburg, Munich, Cologne): Direct 1&1 5G standalone — speeds and latency competitive with O2, behind Telekom and Vodafone.
• Mid-sized towns: Mix of 1&1 5G and Vodafone fallback — mostly transparent to the user.
• Rural areas, Alpine valleys, Baltic coast: Vodafone fallback dominates. Performance equals a Vodafone host MVNO — serviceable but behind Telekom (D1).
• Indoor reception: The 1&1 sub-6 GHz spectrum is shallower than Telekom’s 700 MHz holdings — expect more weak-signal moments inside dense buildings.

What’s the difference in customer service?

1&1 retail + phone + English · SIM.de online only · winSIM online only

This is where the premium-vs-discount split shows up most clearly. 1&1 ships full-fat service: phone hotline, English-language agents, retail shops, household-bundle account management, and a measurable response SLA. SIM.de and winSIM are deliberately stripped down to web forms and email tickets — the savings come from cutting that overhead. If you ever need a human on the line, 1&1 is the only one of the three that delivers it.

Source: operator service pages, verified May 2026.

What are the pros and cons of each?

Strengths and weak spots, side by side

Each brand makes a different trade between price, support, and contract flexibility. None is universally “better” — the right choice depends on whether you weight ongoing price or service depth more heavily.

Should you pick 1&1, SIM.de, or winSIM?

One decision rule per scenario · Which question to ask yourself first

The decision rule is simple: pay for service or pay for data. If you might need to call a hotline or visit a shop — especially as a newcomer to Germany still working through Anmeldung paperwork — the €5–10/month premium for 1&1 is worth it. If you’re confident handling the contract online and your priority is €/GB, SIM.de or winSIM deliver the same network for less.

• Pick 1&1 if: you want phone + English support, plan to use a 1&1 broadband bundle at home, value retail-shop access, or want to lock in the €9.99 intro rate and reassess in 3 months.
• Pick SIM.de if: you sort by €/GB, need 40–90 GB of data per month, are comfortable with online-only self-service, and don’t need English-language support.
• Pick winSIM if: you want the absolute lowest monthly price, your data needs are modest (10–20 GB), you’re happy to chase promo codes, and you don’t need a phone hotline.
• Skip all three if: you live in rural Germany or the Alps where Telekom’s D1 network is meaningfully better — see our Telekom vs Vodafone comparison.

For most expats and digital nomads sorting tariffs in 2026, SIM.de 40 GB at €8.99/month is the rational default: identical network, half the price, online-only friction. Move up to 1&1 only if you need the support layer; move down to winSIM only if 10–20 GB is genuinely enough.

How do you switch between them while keeping your number?

Porting rules · Internal Drillisch caveat · 5 steps

Number portability under BNetzA / TKG § 59 applies to all three brands, but with a critical caveat: because 1&1, SIM.de, and winSIM share a parent legal entity, you cannot port your number between them internally. Porting only works when you arrive from a different carrier or leave for one. The process otherwise takes 1–7 working days; the porting fee is capped at €6.82.

1. Check eligibility. If you’re moving between Drillisch brands (e.g. winSIM → 1&1), porting is blocked — you’ll need to accept a new number or wait, cancel, and re-port after a gap with a different carrier. If you’re arriving from Telekom, Vodafone, O2, or any MVNO on those networks, you’re fine.
2. Request your Rufnummernmitnahme code from your current provider. By law since December 2021 this must be issued within one working day. Telekom, Vodafone, and O2 all issue it via app or web portal. (in German called the “Portierungscode” or PAC equivalent)
3. Sign up for the new tariff and submit the port-in request. All three of 1&1, SIM.de, and winSIM have a port-in checkbox at checkout — enter the code, your existing number, and the prior carrier’s name.
4. Wait for the porting date. Standard is 1–7 working days. You can request “immediate” porting (Sofortportierung) which usually completes within 24 hours but costs the prior provider the €6.82 fee.
5. Insert the new SIM (or activate the eSIM) on the porting date. Your old SIM stops working at the moment of cut-over; the new one activates within a few minutes. Test by placing a call to a landline to confirm the number transferred. (you keep your contract with the old provider until the cancellation date you set separately)