A thorough assessment of the UK’s four main mobile networks has seen EE emerge as the clear winner
In the UK, four main mobile networks compete to provide the best signal and service for calls and data. Even if you opt for a smaller, challenger brand, they typically lease network access from one of the big four – EE, O2, Three or Vodafone – so your options for quality coverage are ultimately limited.
The latest RootMetrics report, from the network analytics firm owned by connectivity giant Ookla, shows one UK mobile network won or tied in all eight categories of its nationwide test. The results are based on data collected over six months, from July to December 2025.
According to RootMetrics’ State of the Mobile Union Report, EE is the UK’s leading mobile network, winning in overall performance, reliability, responsiveness, speed, data, call and video categories, while sharing the top spot for texts with Three and O2.
“EE remained the leader in 2H 2025, winning or sharing every UK-wide RootScore during testing,” said Luke Kehoe, analyst at Ookla.
“In fact, EE has won our UK Overall RootScore Award outright in every test period since 2H 2013, earning recognition as the UK’s best network for over 12 years and counting. EE also posted the fastest UK-wide aggregate median download speed at 114.1 Mbps, more than double the next-fastest result (Three’s 53.8 Mbps).”
Technically speaking, Ookla attributes EE’s dominance to “an aggressive focus on spectrum maximisation”. Spectrum refers to the frequencies mobile networks use to deliver cellular signals to phones and smartphones. EE is said to strike the best balance between capacity – how many devices can connect to a single mobile mast at once – and consistent performance.
“Despite not holding the largest contiguous 5G spectrum blocks, EE achieves the highest median 5G download speed and overall reliability in the market,” Ookla said, highlighting the BT-owned network has leveraged its existing 4G infrastructure most effectively to deliver a strong 5G service.
RootMetrics reported during the six-month testing period, it conducted over 600,000 mobile connection tests across the UK, covering all four major networks.
The tests measured performance at peak and off-peak times, both while stationary and driving on motorways in areas of strong and weak coverage and across indoor and outdoor locations throughout Scotland, England, Wales and Northern Ireland, the Express reports.
While EE claimed the top spot, Three delivered a strong second place performance in all categories expect video. RootMetrics reported Three’s average UK-wide download speeds reached 53.8 Mbps, which was faster than both O2 and Vodafone, but still well below EE’s 114.1 Mbps.
Meanwhile, the report noted O2 has boosted its speeds in major cities and improved its nationwide reliability, climbing to second place behind EE after finishing fourth and last in the first-half 2025 results.
Vodafone saw a drop in its total awards, but Ookla said the network “remains competitive in key regions”.
Even though EE leads this particular ranking of UK mobile networks, it may not be the right choice for everyone. If you’re considering switching providers, it is a good idea to use the online coverage checkers offered by each network to see how strong the signal is in your area.
It’s also worth shopping around for the best deal, including checking out mobile virtual network operators (MVNOs) like Giffgaff or Tesco Mobile, which lease coverage from the big four. This can be a great option if you already own your phone, allowing you to get a monthly rolling contract at a much lower cost than signing up for a new phone contract.