Telekom, Vodafone or O2 - whichever has signal
This eSIM can use any of Germany's three established nationwide networks: Telekom, Vodafone and O2 (Telefónica). That matters in the countryside, where each network has its own gaps - Germans call them Funklöcher. If one drops out, pick another from the network list in your phone's mobile settings.
According to the regulator, the Bundesnetzagentur, about 97.5% of Germany's area had 4G from at least one network in January 2025, and its online Funkloch map shows where coverage is thin.
On an EU SIM? You may not need this
A SIM from an EU or EEA country already works in Germany at home prices under the EU's roam-like-at-home rules, within your operator's fair-use allowance. This eSIM is mainly for everyone else: the UK has not been covered since it left the EU, and Turkey, Switzerland and the US never were. On an EU SIM it is still useful if you need more data than your allowance.
On the train: ICE WiFi and the gaps between
Deutsche Bahn offers free WiFi on every ICE, in first and second class, with no time limit. It is shared by the whole train, and DB asks passengers to avoid heavy streaming and downloads. Only some IC and regional trains have WiFi, so the eSIM is what keeps you online on regional trains, the S-Bahn and trams, or when the on-board WiFi drops.
Why not just buy a German SIM?
You can, but German law requires your identity to be checked before a German prepaid SIM is activated - often by video call or in a shop. This eSIM is bought online before you travel, so there is no German ID check or shop visit, and it carries data only, with no German number.