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How fast is 4G? - 4G speeds and UK network performance

4G Speeds

You’d have to be living in a cave to not know 4G was faster than 3G, but just how much faster is it really? And what practical difference does the speed make? We've got the answers.

To understand just how fast 4G is we need to put the technology into perspective against the older mobile network technologies, namely 3G and 3G HSPA+. To do so we'll look at the theoretical and real world performance of 4G LTE, as well as looking 4G speeds on the UK's mobile networks.

Theoretical/Real World Speeds by network technology

When it comes to measuring mobile network speeds there are two situations which are of interest, theoretical and the real world.

Theoretical speeds are those which you can expect to obtain in a laboratory environment with perfect conditions, while real world speeds are those you can expect to get everyday using your phone on a real mobile network.

To benchmark network speeds we are interested in download and upload speeds.

Download speeds are the rate at which mobile data is transferred from the internet to your phone or mobile device e.g. downloading a video. While, upload speeds are the rate that mobile data is transferred from your phone or mobile device to the internet e.g. uploading a photo to Facebook.

Theoretical-4G-Network-Speeds Real Word 4G Network Speed

3G, as offered by most networks, is the slowest speed you’ll usually be browsing on. It has a typical real world download speed of 3Mbps and a theoretical maximum download speed of 7.2Mbps. If you want to steam a video via 3G from YouTube for example you could be waiting up to ten seconds for it to load. While downloading a 500MB file can take around 22 minutes, with larger apps, movies and albums taking far longer still.

Basic 3G‘s upload speed is a lot slower than its download speed, with typical speeds of 0.4Mbps and a theoretical limit of 2Mbps. In practice 3G is generally fine for web browsing and social networks, you’ll just have to wait a few seconds for pages to load. It would take 25 seconds to upload a 10MB file or image.

3G HSPA+ is an enhanced version of 3G, which for example Three uses for its Ultrafast service. It offers typical download speeds of 6Mbps and a theoretical maximum of 42Mbps . You can expect streaming videos to load in around 5 seconds and medium sized apps to download in one minute plus, whilst the same 500MB file mentioned above would take 11 minutes to download.

3G HSPA+ provides upload speeds of around 3Mbps and the theoretical maximum is around 22Mbps. A 10MB file or image would take just over 8 seconds to download.

4G (4G LTE) is the fastest speed that’s widely available in the UK right now. It offers typical download speeds of 14Mbps and theoretical ones of 150Mbps. So for example you could download a medium sized app in under 20 seconds or load a YouTube video in just 2 seconds. The same 500MB file should be downloadable in under 5 minutes.

4G  boosts upload speeds to 8Mbps on average and 50Mbps at the very top end. The same 10MB file or image would take just 1.25 seconds to download.

4G LTE-Advanced is a faster version of 4G with typical real world download speeds of 42Mbps and theoretical limits of 300Mbps. EE has launched this service in London under the name 4G+,  while Vodafone has rolled it out to London, Birmingham and Manchester. With LTE-Advanced (also known as 4G+, LTE-A or 4.5G) videos will load without a discernible pause and a 500MB file will download in under 2 minutes. In fact it’s even faster than many home broadband connections.

4G LTE-Advanced offers upload speeds of 30Mbps and can theoretically reach 150Mbps. In this case the same 10MB file or image would take just 0.33 seconds to download.


Download and upload speeds aren’t the only things that have been improved because 4G also has a better response time than 3G – due to lower “latency”. This means that a device connected to a 4G mobile network will get a quicker response to a request than the same device connected to a 3G mobile network.

The improved latency times, reduced from 120 milliseconds (3G) to 60 milliseconds (4G), may not seem that significant on paper. However, they can make a significant difference when playing online games and streaming live video.

UK Network 4G Speeds - Which UK network offers the fastest 4G?

There have been a number of studies conducted to compare 4G speeds on the UK's 4 major networks, but we've picked out the two most important ones which are research published by OFCOM in April 2015 and Speedtest.net fastest Mobile Network 2015 study.

Speedtest - Fastest Mobile Network

Network Download/Upload Speeds (Mbps) Check Speeds In Your Area
EE 33.03/13.81
Vodafone 20.70/10.11
Three 18.92/9.80
O2 18.48/9.40

The most recent comprehensive study into 4G speeds on the UK's network was conducted by Speedtest using real benchmarks gathered from users across the UK using it's website or mobile app. EE's network was the clear winner with significantly higher average download and upload speeds across the UK.

Ofcom- 4G performance across networks, Q4 2014

Network Download/Upload Speeds (Mbps) Latency (ms)
EE 18.6/4.0 48.4
Vodafone 16.4/7.6 59.5
O2 13.9/6.6 55.2
Three 8.5/5.4 50.9

An older study by OFCOM showed a similar result with EE coming out on top. However, it's interesting to see how all the networks have significantly improved performance in the last year with Three and EE in particular making huge improvements to their 4G network performance since this study was conducted.


EE are still clearly the fastest 4G network with speeds up to 50 per cent faster than the other 3 networks. Vodafone, Three and O2 are now on a pretty level footing across the UK in terms of average 4G upload and download speeds. However, it's interesting to note the huge gains made by Three in the last year who more than their speeds in less than a year and their network will get another huge boost after Three's acquisition of O2 is completed.

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