If you buy a smartphone from a mobile operator you can expect it to work properly. But what if you buy one second hand or SIM-free? Things get a little trickier so here we explain the UK mobile operator frequency bands and how to tell whether a phone is supported by your network. See: 19 best new phones you should be most excited about in 2016: best new phones coming from Apple, Samsung, Sony, HTC, LG, Xiaomi and others.

EE, O2, Vodafone and Three all have 4G networks available in the UK but it's not as simple as buying a '4G ready' smartphone, plonking your SIM card in and enjoying blazing fast speeds. Different networks use different frequency bands so compatibility is an issue.

These days any smartphone you buy will work on a 3G network, no matter which operator you go with. In this article, we're focussing on 4G LTE because it's this area which is complicated. Read through this article to find out everything you need to know about 4G bands, networks and smartphone compatibility.

Update 19 September 2016: A useful website willmyphonework.net has recently been brought to our attention, and can quickly show you whether a phone will work on your operator's network and which network bands it will cover. Just head to the site, use the drop-downs to select your phone (be sure to get the exact model number), your country and your network, and it will then show you how it will manage 2G, 3G and 4G connections. 

UK 4G LTE bands, frequencies and numbers

In the UK there are three different 4G LTE frequencies in use: 800 MHz, 1800 MHz (1.8 GHz) and 2600 MHz (2.6 GHz). Two of these – 800 MHz and 2.6 GHz - were auctioned in 2013 by Ofcom to various parties. Then the regulator allowed EE to use 1800 MHz for LTE which it already had access to and subsequently shared with Three.

If LTE bands are given in numbers you're looking for 3, 7 and 20 – 1800 MHz, 2600 MHz and 800 MHz respectively. See: UK's best mobile network.

As a rule of thumb the lower frequencies are better at travelling long distances so are more suitable for rural areas where there are fewer masts. They also travel through walls better so provide decent indoor coverage. The higher frequencies effectively are the opposite, but they're not useless. The higher capacity (35 MHz or even 45 MHz) means more capacity and can therefor cope with more users in populated areas all connecting at once.

Below is a table of which UK mobile network uses which 4G LTE frequencies and in what bands. Afterwards we'll explain what it all means.

 

800 MHz

1800 MHz

2600 MHz

EE

2 x 5 MHz

2 x 45 MHz

2 x 35 MHz

Three

2 x 5 MHz

2 x 15 MHz

-

O2

2 x 10 MHz

-

-

Vodafone

2 x 10 MHz

-

2 x 20 MHz and 1 x 25 MHz (unpaired)

4G LTE smartphone

How to tell whether a phone is supported by your network: EE

As the table suggests, EE is in a great position for 4G since it offers all three frequencies and with decent capacity. This means most 4G smartphones will support at least one of the three.

Virgin Mobile runs its virtual network on EE but its 4G services are limited to business customers.

How to tell whether a phone is supported by your network: Three

Like Vodafone, Three is able to offer two different frequencies thanks to the aforementioned deal with EE. You'll need a phone with either 800- or 1800 MHz LTE support to use Threes 4G network.

How to tell whether a phone is supported by your network: O2

As you can see from the table, O2 has the least amount of frequencies on offer with just 800 MHz – this is what caused controversy when the iPhone 5 launched as it didn't come with support for this frequency. You'll need to buy a phone which supports 800 MHz otherwise it won't work with O2's 4G network.

Virtual networks Tesco Mobile and GiffGaff both use O2's 4G network so also use the 800 MHz spectrum.

How to tell whether a phone is supported by your network: Vodafone

Vofafone matches Three with two frequencies available but 800- and 2600 MHz. To use Vodafone's 4G LTE network your phone will need to support at least one of the two.

TalkTalk currently uses Vodafone's network but doesn't offer 4G tariffs. It will be moving to O2, though.

How to tell whether a phone is supported by your network: Specifications

We've explained all the frequencies for each network, but how do you tell if your smartphone supports the right ones for the network you want to use? There are a few different things you can do.

The first and easiest is to use a checker tool but only Three appears to have one. Simply head to the page and select your particular device to see if it's supported.

If you're not looking at Three then you need to check the specifications of the device you own or are looking to buy. Either go to the manufacturer's page (example below) and search for the technical details or use a site like GSMArena.

As mentioned earlier, if bands are quoted in numbers like Google does with the Nexus 6 below, the bands you are looking for in the UK are 3, 7 and 20.

Nexus 6 specs 4G LTE

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