Ookla Award Three UK and Vodafone Fastest for 5G Mobile Speeds in H1 2025

Network testing firm Ookla, which collects data from consumers via their popular broadband Speedtest.net service, has published their Q1-Q2 2025 (H1) study into the speed of 5G based mobile broadband networks across the United Kingdom. The results reveal that Three UK continues to hold the top spot, followed by merger partner Vodafone.

The catch here is that mobile broadband performance can be a very difficult thing to pin down because related users are always moving through different areas (indoor, outdoor, underground etc.), using different devices with different capabilities and the surrounding environment is ever changeable (weather, trees, buildings etc.). And that’s before we consider the other issues, such as network capacity and varying spectrum use at different cell sites.

Nevertheless, Ookla used data collected from 379,025 samples (users) and 2,188,229 speedtests, conducted across the UK, to identify the best performing 5G mobile operator. This saw Three UK come top with a “Speed Score” of 55.17, median average download speeds of 227.77Mbps and median upload speeds of 13.07Mbps.

Just to be clear, Ookla’s Speed Score is produced using data from various metrics, including the 10th, 50th, and 90th percentiles of download and upload throughput and loaded latency. Different aspects of these have different weightings in the final score, for example, download speed is most relevant (70%) to the end result, while upload speed counts for 20% of the weighting and latency just 10%.

Take note that if you’re a fan of fast-paced online multiplayer games, for example, then you might well put more emphasis on uploads and latency times than this study does.

Fastest UK Mobile Operators by Speed Score – H1 2025

1. Three UK 55.17

2. Vodafone 45.04

3. EE (BT) 38.46

4. O2 (Virgin Media) 31.13

The results will naturally change as Three UK and Vodafone slowly bring their respective networks together following the recent merger, which is now in the process of creating a single network under the VodafoneThree brand. But this will require the new company to strike a careful balance between the desire for cost efficiency and performance, which may well result in some positive and possibly also a few negative changes to network performance, depending upon where you live.