Which provider has the fastest mobile broadband?

Which UK mobile network offers the fastest mobile broadband? Broadband speed assessor Ookla, which offers internet speed test services, has published its biannual report investigating just that.  

Ookla uses data from hundreds of thousands of users to assess what mobile internet speeds customers are receiving. This data is used to give each supplier a speed score, which can then be compared both to other suppliers and across time periods. Here’s what the report for Q3 and Q4 of 2025 shows us. 

Three is the UK’s fastest mobile network

Of the UK’s four mobile carrier networks*, Three received the highest speed score in the second half of 2025. In the table below, you can see how each supplier scored, as well as the speed scores for the first half of 2025. 

* Since Three and Vodafone merged last year, there are now only three mobile carrier networks in the UK. Ookla’s data is from both before and after the merge, so they’ve kept the scores separate for now. Future reports will reflect the combined Three and Vodafone networks. 

What is a speed score?

Rather than just comparing average download speeds, Ookla uses speed scores to more accurately reflect what internet speeds customers actually experience. Ookla uses data from the 10th, 50th, and 90th percentiles of users to reflect the full spectrum of user experience. The speed score includes data on download speed, upload speed and latency. Extra weighting is given to download speeds in the final score, as this is the most important figure for typical users. 

Is Three the best mobile network in the UK?

Based on speed scores alone, it would seem that Three is the UK’s best network for mobile broadband users. Three users received the highest median and 90th percentile download and upload speeds, and the lowest loaded latency for downloads. 

However, speeds don’t tell the full story. Three UK also had significant network downtime last year. In fact, the issue was so bad that it is now under investigation by telecoms regulator Ofcom. Choosing your supplier based on who offers the fastest mobile broadband might seem sensible, but it doesn’t matter how high your theoretical download speeds are if you can’t get online to use them. 

How to get the benefits of speed and reliability

If you want the fastest mobile broadband in your area, while also knowing you’re covered if the supplier has a blackout or you move to an area with different coverage, we recommend multi-network mobile broadband.  

Multi-network mobile broadband means that, rather than signing a contract with a specific mobile supplier and being locked into their service, you are free to switch between any of the UK’s carrier networks based on which offers the best speed and signal quality in your area. If that ever changes, switching networks is as simple as changing SIM cards. 

We think it’s the best option, hands down. That’s why all our plans offer multi-network mobile broadband as standard. Don’t get locked into a single network. Choose My Connectivity, and stay connected to the best network, always.