What can affect mobile signal strength or reception?

Your phone signal reception depends on how easily your mobile device can communicate by radio waves to the nearest network mast antenna or base station.

The further away a network antenna is from your mobile phone, the weaker the signal is, as the radio waves need to travel further to reach it.

Places with more network antennas that are located closer together provide better mobile network coverage in the area.

Radio waves are also affected by buildings and obstacles. So if you are surrounded by thick walls or in a tunnel or basement, this can reduce the mobile signal strength that you receive.

What is WiFi Calling?

WiFi Calling allows you to make and receive phone calls (and texts) on your mobile phone using a wi-fi connection instead of the traditional mobile network.

It is especially useful when you have low or no signal indoors or in rural locations, and are able to connect to a Wi-Fi network.

Not all mobile networks offer Wi-Fi Calling as a feature so check with your provider to see if it available as part of your plan.

Calls made using WiFi Calling are charged at the same rate as your regular mobile calls, so will use your monthly minutes allowance if you have any, or priced at your plan's standard call tariff.

Note: WiFi Calling is different to apps that allow you to make calls over the Internet (VoIP) such as: WhatsApp, Apple FaceTime, Facebook Messenger, Skype, Telegram, etc. These apps can be used to make voice or video calls over the Internet regardless of whether you have the Wi-Fi Calling feature available to you or not.

What is 4G Calling?

4G Calling (also known as VoLTE or Voice over LTE) is a service offered by some mobile networks that lets you make and get clearer phone calls over a 4G network.

With 4G Calling you get clear HD (high-definition) sound on your voice calls, and you can use your mobile internet at the same time with no slow-down while on a 4G call.

To make use of 4G Calling, you need to have:

  • The 4G Calling service available from your mobile network provider.
  • A compatible mobile handset (Android or iPhone) that supports 4G Calling.
  • Enable 4G Calling in your mobile phone settings.
  • 4G network coverage in your location at the time of the call.

Note: Phone calls made through 4G Calling are treated as normal calls and so will come out of your monthly minutes allowance or charged at your plan's standard call tariff.

What is an eSIM card?

An eSIM (embedded-SIM) is a digital virtual SIM card that is built into some newer mobile devices.

Instead of having to manually insert a physical SIM card into a mobile handset, eSIMs allow you to simply download the SIM (Subscriber Identity Module) information from your network provider directly to a device that contains a built-in e-SIM.

This allows you to easily change mobile network providers (that support eSIM UK) without having to order a physical SIM card and wait for it to be delivered.

Mobile smartphones that support eSIM cards also enable using dual SIM so that you can use two different numbers on the same handset.

eSIM is a fairly new technology and so not all mobile network providers or mobile devices support e-SIM cards at the moment, but as eSIMs become more popular, support for them will continue to grow, until they eventually replace physical SIM cards in the future.

Which mobile devices support eSIM?

The number of mobile handsets that feature eSIM support is ever increasing as new smartphone models are released. Below is a list of some of the latest mobile devices that have an eSIM card:

Apple iPhone eSIM models

Apple iPhone 14, iPhone 14 Plus, iPhone 14 Pro, iPhone 14 Pro Max, Apple iPhone 13, iPhone 13 Pro, iPhone 13 Pro Max, iPhone 13 mini, iPhone 12, iPhone 12 Pro, iPhone 12 Pro Max, iPhone 12 mini, iPhone 11, iPhone 11 Pro, iPhone 11 Pro Max, iPhone XS, iPhone XS Max, iPhone XR.

Google Pixel eSIM phones

Google Pixel 7, Google Pixel 7 Pro, Google Pixel 6, Pixel 6 Pro, Pixel 5, Pixel 4a, Pixel 4, Pixel 4 XL, Pixel 3a, Pixel 3a XL, Pixel 3.

Samsung Galaxy eSIM handsets

Samsung Galaxy S23, Galaxy S22, Galaxy S21, Galaxy S20, Galaxy Z Flip, Galaxy Fold, Galaxy Note.

Android eSIM devices

Huawei P40 Pro, OPPO Find X3 Pro, Motorola Razr 5G.

What is a Mobile Virtual Network Operator (MVNO)?

Mobile Virtual Network Operators (MVNO) are mobile phone service providers that do not run their own network infrastructure but instead use that of one of the 4 major UK mobile network operators: EE, O2, Three or Vodafone.

These four main UK mobile networks, deploy, operate and maintain their own infrastructure (radio masts, cell towers, etc) and through lease arrangement, enable the other MVNO UK providers to run on their networks in order for the MVNOs to offer their own mobile phone services to their own customers.

The advantage of a UK MVNO is that as a consumer, you have more options on which mobile network to join based on your own personal preference for tariff, plan, speed, cost, customer support, features, or other benefits provided.

The mobile network signal coverage of MVNOs in the UK will usually be the same as the host network provider that they use, however this might not always be the case.

Depending on the agreements between the MVNO and the host network operator, certain services may not be available (for example 5G, VoLTE, WiFi Calling, etc) or the network capacity and mobile internet speed may be limited on the MVNO to ensure customers of the host network are not negatively impacted during busy periods when the network is congested.

It is recommended to always check which mobile services are offered and what the network signal coverage is like in your area before selecting any mobile network provider, as this can affect your phone call quality and mobile internet speeds.

What is the difference between 4G and 5G?

5G is the 5th and latest generation of mobile network technology, launched 2019 in the UK. It is a big improvement in terms of faster internet speeds over the previous 4G technology, with average data speeds of around 100Mbps to 200Mbps and a current max of up to 1Gbps (1000 Mbps), making 5G up to 100 times faster than 4G.

Operating at higher frequencies, 5G also provides greater bandwidth and capacity for more devices to be connected and using the internet at the same time, while maintaining a fast connection with low latency (lag/delay).

This makes 5G a particularly great technology in highly-crowded and congested areas, where typically, mobile users notice a slow down or degradation of speed, signal and performance as the service is spread too thin between many connected devices in a particular location.

Only 5G compatible mobile devices (e.g. iPhone 12, Google Pixel 5, Samsung Galaxy S20 etc.) are able to take advantage of 5G services and only in locations where 5G coverage is available. Although the technology is backwards compatible, so that a 5G mobile phone can also use a 4G network or 3G signal as normal.

What is the difference between 3G and 4G?

4G is the 4th generation of wireless mobile technology and launched in 2012 in the UK. 4G typically provides between 5-7 times faster internet speeds than 3G technology. With the upgraded data speeds, 4G enables smooth streaming of HD quality video and music.

Mobile phones that support 4G calling (i.e. VoLTE or Voice over LTE) allow you to make higher quality and clearer voice calls over 4G coverage where available.

All new mobile phones released today should be at least 4G compatible, but much older phones may only be compatible on 3G (or 2G) networks.

It's worth noting that newer generation devices are backwards compatible with older generation networks, so for example a 4G mobile phone will work on a 3G network when 4G coverage is not available in the current location.

What is the difference between 2G and 3G?

Ignoring the first generation (1G) of mobile phone technology in the 1980s which was analogue and voice only, 2G or 2nd Generation took things digital in the 1990s and provided SMS text messaging and MMS (multimedia messaging service).

2G introduced (slow) network services on mobile phones, with maximum speeds ranging from 50 Kbps for GPRS (2.5G), to 384 Kbps with Enhanced Data Rates for GSM Evolution (EDGE or 2.75G).

The 3rd Generation (3G) was the beginning of the smart phone era and with upgraded data speeds (2mbit/s) allowing for video calling, better web browsing and mobile email access. 3G launched in 2003 in the UK and enabled faster mobile internet and the possibility of mobile broadband.

What is the 3G network switch-off?

The 3G network switch-off is an agreement between the UK government and the four main mobile networks operators (EE, O2, Three, Vodafone) to shutdown their 3G networks over the next few years to focus on freeing up that space to expand 4G and 5G network coverage throughout the United Kingdom.

Along with 3G networks, 2G is also planned to be phased out by 2033 across the UK. This phase is expected to happen gradually over the next decade once the shutdown of 3G has been completed.

What are mobile network frequency bands?

Mobile phones and devices operate using an antenna to send radio waves over a range of frequencies or bands. These radio wave signals are transmitted to and from your mobile device through cell towers, network masts and base stations.

Each mobile network operator is allocated specific radio frequencies and bands that they can use to provide network coverage, and so the radio frequencies and bands that a mobile phone device supports determines which networks it can use.

Mobile phones sold within the UK are designed to work on all UK mobile network frequencies, and as long as the handset is unlocked (i.e. not network locked) then should work on any UK network.

If you are looking to purchase or use an imported mobile phone within the United Kingdom then it is advisable to check which radio frequencies are supported by referring to the technical specifications of your particular handset model, and crosschecking it with the UK Network Frequency Bands to see if the device is compatible with a UK mobile network.

Is there national UK roaming?

Unfortunately not with a UK SIM, only if you are using a mobile SIM card from another country while in the United Kingdom.

Roaming allows mobile phones to connect to a different network when their own one is unavailable in that location, but this only applies when roaming abroad.

Within the UK there is no specific agreement between the major mobile operators to share network masts and infrastructure. This is unfortunate because if national or domestic roaming were available it would allow mobile handsets to seamlessly switch between different phone networks if one has no mobile signal or poor coverage in a particular area.

Can I check mobile network coverage in my area?

Yes, Ofcom provide a mobile signal checker to check your location for network signal availability of voice, 2G, 3G, 4G, and 5G services from the four main UK mobile network operators (EE, O2, Three, Vodafone).

Since all the other UK mobile network operators run using one of the above networks, you can use the information to find out signal coverage for any mobile service provider once you know which underlying network they use.

What is Ofcom?

Ofcom (The Office of Communications) is the independent telecommunications regulator within the United Kingdom, that overseas mobile phone network operators, fixed-line telephone and broadband internet service providers.

Ofcom work to improve communications services for everyone, making sure people get the best from their telecom providers by promoting good practices and competition among companies they regulate in the UK.