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Which mobile phone network has the best coverage?

By Jon Barrow

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Which mobile phone network has the best coverage?

In spring 2016 we found that Three and EE were tied as the fastest 4G networks, but our results from the autumn show that one provider has now pulled ahead

We regularly work with independent coverage experts OpenSignal to report on the state of mobile phone networks in the UK.

In our latest research, published in autumn 2016, we've focused on 4G performance. We looked at network performance from June to August 2016 and found that while Three and EE had previously tied for first place in our 4G-speed rankings, the latter has now pulled clear of its rival.

EE's 4G download speeds were, on average, more than 3Mbps faster than those of Three, and well ahead of those offered by O2 and Vodafone.

EE was also at the top of the pile when it came to the availability of its 4G signal, with customers able to access it 64.1% of the time.

The conclusion is clear – if 4G is important to you, then EE is your best bet.

However, speed and network availability shouldn't be your only consideration when choosing a provider – customer service and value for money can be just as important.

See how EE customers rated the network in our latest mobile phone satisfaction survey.

4G speeds

 

New OpenSignal data revealed that, in the summer of 2016, EE customers received the fastest average 4G speed – 28Mbps. That's a lot faster than many home broadband connections.

Three, which had matched EE's speeds when we looked at network performance earlier in the year, has now dropped back into second place, though its customers still typically experience far faster speeds than O2 and Vodafone users.

4G availability

 

But speed is only part of the story – after all, a superfast service is of little use if you can never get a signal.

Here, Three shows its limitations as a 4G provider. While the network upgrades it has undertaken may have boosted its speeds, they haven't led to substantial boosts in its 4G coverage. Customers are still only able to access the 4G network 43.7% of the time; in comparison, customers with EE, the best network, were able to get a 4G signal 64.1% of the time.

Combined 3G and 4G speeds

Network Average combined 3G/4G speeds Average 3G speeds
3 12.9Mbps 6.1Mbps
EE 18.6Mbps 5.5Mbps
O2 11.1Mbps 4.1Mbps
Vodafone 12.3Mbps 4.8Mbps

The table above shows the average download speeds if people use both 3G and 4G networks, or are restricted to 3G-only access.

It shows the impact of Three's limited 4G coverage – Three customers that move between 3G and 4G  signals experience lower average speeds (12.9Mbps) than those using EE's network (18.6Mbps) because they spend much more time connected to the slower 3G network.

However, the good news is that Three does offer the fastest 3G-only service (6.1Mbps).

O2 has the lowest combined speed (11.1Mbps), partly because its 3G network offers the lowest average speeds (4.1Mbps).

Best regional mobile phone coverage

As well as national speed and availability information, we also compared performance in 12 regions across the UK.

Surprisingly, our data showed that, while London may offer the best chance of getting a 4G signal (available 69.7% of the time), it had the lowest average 4G speed (18.8Mbps). In comparison, 4G customers in Northern Ireland received an average speed of 23.3Mbps.

Read our full regional phone coverage report to find out more.

Methodology

The information in this report is based on more than 500m data readings taken from people that have downloaded the free OpenSignal app. In total, OpenSignal tracked 28,841 UK app users around the clock between June and August 2016, checking every 15 minutes whether they had a signal.

It then analysed this data to calculate download speeds and network availability.

We think that reporting on availability – that is, the proportion of time that users actually have access to a particular type of signal – is far more useful than simply stating geographical coverage, which is normally based on computer estimates or one-off drive-by assessments. After all, this shows whether users can get a signal where they need it and is therefore a more accurate reflection of the real-life experience.

How you can help

As well as using data from its app to produce these reports, OpenSignal also uses it to generate a free online coverage checker. You can use this to determine the best network for where you live.

To ensure that our reports and the interactive map are accurate, we require as much data as possible. To help provide this, we need you to download OpenSignal's free Android or iPhone app.

The data collected is stripped of any identifying information and uploaded to OpenSignal's servers, taking care to use as little processing power and battery life as possible.

You can read more about the apps and the coverage map on OpenSignal's website.