A life without internet is hardly imaginable for most people today. With just a few clicks, we can receive data from the farthest corners of the world or send it across the globe in a split second. Communication, online shopping, streaming, online banking – the internet permeates all areas of life, both personal and professional. Statistics show that over 90 percent of private households now have internet access. Most consumers opt for one of the four major fixed-line internet providers: Deutsche Telekom, Vodafone, 1&1, and O2 Telefónica. Together, these four supply internet to about 85% of households, with Deutsche Telekom leading the pack at over 40% market share. The remaining 15% are served by smaller, predominantly regional providers.
Performance Over Price: Consumers Value Quality
Whether consumers remain loyal to a provider depends on more than just price. According to a survey by a comparison portal, 43 percent of Germans consider the internet as important as electricity and heating. Increasingly, they focus on the quality of service provided – especially the reliability and stability of the internet connection.
zafaco Puts Fixed-Line Internet to the Test
As technology advances, so do the demands on private internet connections. In just four years, the average fixed-line internet speed has increased from just under 58 Mbit/s in 2021 to around 100 Mbit/s in 2025. At the same time, the overall stability of fixed-line internet connections has improved. Nevertheless, regular outages remain common and are a major annoyance for users – and often the main reason for switching providers.
Through its fixed-line internet provider test, zafaco – in cooperation with IMTEST, the renowned testing and consumer platform of the FUNKE media group – offers a well-founded and comprehensive overview of the performance of both national and regional providers.
Long-Term Testing for Meaningful Results
In addition to years of experience, zafaco relies on continuously updated and refined state-of-the-art testing methods. The test results presented by IMTEST in early July are based on continuous monitoring as part of a long-term test. This approach ensures meaningful results on network stability and performance, which are difficult to compare with traditional, one-time connection tests. zafaco can also detect, compare, and evaluate fluctuations based on time of day and corresponding network load.
Real-Life Testing for Practical Results
zafaco places particular emphasis on realistic testing scenarios in its fixed-line internet provider tests. Laboratory conditions are generally of little relevance to consumers, and abstract results often lack practical value. Instead, zafaco simulates realistic usage conditions – especially in multi-person households. In these settings, multiple devices such as desktop PCs, tablets, smartphones, smart TVs, and other IoT devices are typically connected simultaneously and must share the available bandwidth. Even under these conditions, consumers expect stable connections and smooth performance.
Test Results: Strong Performances – but Not Without Weaknesses
In the latest fixed-line internet provider test, zafaco evaluated providers’ performance across five categories – stability, telephony, data transfer, browsing, and streaming – using a total of 76 quality criteria. The evaluation was based on over 4 million measurements taken between April 28 and May 25, 2025.
The overall results of what is now the most detailed and comprehensive test of its kind in Germany came with a surprise: for the first time since 2021, market leader Deutsche Telekom was overtaken in the overall performance ranking. The top spot this year goes to 1&1. With a marginal difference in final scores (1.31 vs. 1.36), the race between the two front-runners was extremely close, clearly leaving O2 Telefónica (1.76) and Vodafone (2.42) behind. While 1&1 and Telekom continue to set the standard in network quality, zafaco still sees room for improvement for the other two providers – despite their overall “good” ratings.
Regional Providers Hold Their Own
Among regional providers, NetCologne (1.42), Tele Columbus | PŸUR (1.51), and EWE (1.52) also delivered excellent results, ahead of M-net (1.59) and Deutsche Glasfaser (1.68), both receiving overall “good” ratings.
A closer look at the individual evaluation categories explains how 1&1 managed to outperform Telekom. While Telekom maintains a slight lead in terms of stability and telephony, 1&1 outshines its competitors in data transmission performance, general user experience while browsing, and streaming quality – in some cases significantly.
The detailed results, test methodology, and further information on the providers and products tested are available in the current edition of the IMTEST online consumer magazine. In addition to the test of fixed-line internet providers in Germany, zafaco also presents test results for Austria and Switzerland this year.