If you’ve had a phone contract with mobile data for a long while, you’ll know exactly how much things have improved over the past few years.

The introduction of 4G saw speeds increase significantly, but only where you can get coverage. And even in cities with supposedly good 4G, you can still end up with a poor signal or poor speeds.

5G aims to fix all of this, as well as vastly expanding the mobile network’s ability to handle the millions of new devices that will be connecting over the next few years.

Also see the best 5G phone deals around right now.

What is 5G?

As with 1G, 2G, 3G and 4G before it, it’s an umbrella term for the fifth-generation of mobile networks. Within 5G there’s lots of jargon, most of which you really don’t need to know about or worry about – at least not until you need to buy a 5G phone. At that point, you must ensure it has the right specs to work with your mobile operator.

5G will be much faster than 4G. In technical lab tests, 4.5Gb/s (4500 megabits per second) and more has been achieved, but in the real world you can expect between 10 and 20 times better speed than 4G. That’s according to companies including Qualcomm, Huawei and Samsung.

In recent tests in real-world conditions (at Canary Wharf, for example), it has demonstrated that over 1Gb/s is possible, which is a big increase over the fastest 4G speeds.

It means the internet connection on your phone is likely to overtake your home broadband speed by quite a margin. And that applies to upload speeds as well as downloads, so posting a 4K video you’ve just shot on your 5G-capable phone to YouTube as you walk along the high street should become a reality within a matter of weeks.

Currently, 4G speeds are around 10-15Mb/s on average for downloads, which means actual 5G speeds should be between 200 and 400Mb/s - on average. It's possible you'll get up to 800Mb/s or even more.

When can I use 5G?

  • 30 May: EE will turn on 5G in six UK cities
  • 3 July: Vodafone will turn on 5G in seven UK cities
  • August 2019: Three will launch what it says is the UK's 'fastest' 5G network
  • Later in 2019: O2 will also launch its 5G network

EE was the first network to switch on 5G in the UK, switching on the next-gen connectivity in London, Cardiff, Edinburgh, Belfast, Birmingham and Manchester on 30 May.

EE will also roll out 5G in Bristol, Coventry, Leicester, Nottingham, Sheffield, Liverpool, Hull, Leeds, Newcastle and Glasgow, and promises to offer the service in Aberdeen, Cambridge, Derby, Gloucester, Peterborough, Plymouth, Portsmouth, Southampton, Worcester, Wolverhampton and more in 2020.

“These 1,500 sites, which is 10 per cent of our site portfolio, will serve 25 per cent of our customers," said EE CEO Marc Allera, of the cities gaining 5G connectivity in 2019. "One site at Waterloo station carries more than 100TB of data per day. We’ve picked these sites based on where customers need it.”

The company has however been quick to emphasise that it "won’t have 90 per cent 5G coverage to begin with," and says that 5G will be complementary to the existing 4G LTE network, which the company is going to continue to invest in.

Vodafone will be next, turning on 5G in seven UK cities on 3 July. 

It will be available in Birmingham, Bristol, Cardiff, Glasgow, Manchester, Liverpool and London, with a further 12 cities switched on by the end of 2019. 

These are: Birkenhead, Blackpool, Bournemouth, Guildford, Newbury, Portsmouth, Plymouth, Reading, Southampton, Stoke-on-Trent, Warrington and Wolverhampton.

You'll also be able to roam on Vodafone's 5G network in Germany, Italy and Spain, although only in the cities which have it of course.

Even better is the news that having 5G won't cost you any more than 4G, but you will need to switch to a new 5G plan.

Vodafone 5G launch UK

Three says it's investing more than £2 billion into 5G infrastructure, including what it says is "the UK’s leading 5G spectrum portfolio" and the development of new 5G cell sites and rolling out carrier aggregation tech. Its network is due in August.

Which phones have 5G?

Yep, that's right: you can't just use your current phone, since it only supports 4G. You need to upgrade to a phone with a 5G modem, and there aren't many around just yet.

Though its 5G network will come later than EE's, Vodafone has been first to launch a 5G phone in the UK - Mi Mix 3 5G is available to buy now on plans starting at £50 a month (£99 upfront). It is also stocking the Galaxy S10 5G.

OnePlus 7 Pro 5G was the first 5G phone on which you could actually use 5G to go on sale in the UK, via EE. It is available to buy now.

Now also available from EE are the Galaxy S10 5G, Oppo Reno 5G and LG V50 ThinQ

Which phones will have 5G

22 manufacturers including Samsung, Sony, LG, Motorola and Google are all working on 5G phones which will launch in 2019 using Qualcomm's Snapdragon X50 modem, along with Chinese companies such as Xiaomi, Oppo, and Vivo. Huawei will use its own Balong 5000 chipset.

Here are more details on all the 5G phones coming in 2019.

What are the other benefits of 5G?

It’s estimated that by 2020 mobile traffic will have increased more than 30 fold since 2014. That’s partly because people want to stream video when they’re out and about, but also because of the number smartphones has increased considerably.

And it’s about to get a whole lot more crowded. We’re already seeing car manufacturers put 4G SIMs in their vehicles, but when self-driving cars hit the roads they’ll all have a 5G connection. Before long so will all your wearable tech, always-connected laptops and tablets, and eventually even your smart home devices.

Infrastructure such as traffic lights could communicate via 5G to work with cars to ensure the speediest flow of traffic, with other smart city tech no doubt to follow.

As well as being faster than 4G, 5G will be a whole lot more responsive, so you won’t have to wait those few seconds before your YouTube video starts playing. The lower latency and faster speeds should also mean you’ll be able to have much higher quality video calls, which are currently poor quality and often laggy when using 4G.

When will 5G arrive around the world?

Trials are already happening in many places. It will help that most 5G infrastructure can be built on top of existing 4G LTE sites, a model which has been successfully tested in multiple global cities. Still, new antennae need to be built and installed - much like this one being tested on London's Cheapside House:

EE 5G trial in East London

South Korea is typically ahead of others, and around 260,000 people are already using 5G  there. The US will also be among the first countries to have public 5G.

As we'll explain below, 5G is a mixture of different technologies. The graphic below shows that millimetre wave - the stuff which enables the really fast speeds - won't be available in most regions initially. Instead, most places will use 'Sub-6' technology, which runs on a much lower frequency than mmWave.

What is 5G? Samsung prototype phone

How does 5G work?

That’s a tricky question to answer, as it’s a complex technology.

In essence, it mainly uses much higher frequencies than 4G where there is plenty of ‘spectrum’ available. 4G works on frequencies between 2 and 8GHz. 5G will use these frequencies - a type of 5G called Sub-6 - as well as the higher band between 24 and 100GHz.

5G frequencies - mmWave

These higher frequencies are being called ‘millimetre wave’. It refers to the fact that, as frequency increases, wavelength decreases. These shorter waves – just as with 802.11ac Wi-Fi compared with 802.11n – mean much faster internet speeds, but at the cost of shorter working distances.

The simplest way to understand it is with a pipe. Sub-6 is like a longer, thinner pipe that offers slower speeds but over a longer distance. mmWave is like a very short, fat pipe which can deliver huge speeds, but only at short distances.

The problem is that 5G ‘mmWave’ signals can’t easily pass through walls and will be affected by obstacles such as tree branches and even rain. What it means in practice is that there will need to be a lot more mobile transmitters located much closer to the ground to create the necessary coverage. The principle of more, smaller transmitters also means there should be excellent indoor 5G coverage as well as outdoor.

Support for Sub-6 and mmWave will vary from country to country, but the UK will get both in certain cities and Qualcomm's X50 5G modem also features the option to support both types of 5G.

Will roaming work with 5G?

In the UK and Europe 5G will be provided in the sub-6GHz spectrum rather than mmWave - at least to start with - while the US will most likely be the other way round. Most phones and infrastructure will probably support both types of frequency, but the early days of the tech could see companies focus on one or the other.

That means that for the next year or two you won't be able to roam worldwide and access 5G connections, though there probably will be consistency across Europe at least.

It's worth pointing out that you'll still be able to access 4G signals when you roam - any 5G phone will be able to handle 4G and below too - so you'll still be able to make calls and access the internet, you just won't get the highest possible speeds.

Will 5G be in rural areas too?

Millimetre wave is currently a good solution for densely populated areas – i.e. cities – but this kind of technology is too expensive to cover rural areas, so unfortunately your 5G phone will simply use existing 4G signals if you go out of 5G coverage.

Some experts say that 5G will fix the currently awful mobile signal on railway lines, offering ‘seamless’ connectivity so you should be able to binge watch Orange is the New Black on your commute to and from work.

However, that will depend upon how much rail operators – that’s Network Rail in the UK – are willing to invest, as upgrading to 5G isn’t cheap. So don’t expect to see much improvement for several years after 5G is first introduced.