2G

Second generation mobile network known as GSM. Simply put, 2G allows you to send text messages.

3G

The third generation of mobile phone technology, offering better coverage for voice calls and text messaging, as well as providing faster access to the internet. All of our tariffs come with 3G as standard.

3.5G

Also known as HSDPA (High Speed Data Packet Access), 3.5G provides faster data rates than 3G.

4G

The fourth generation of mobile phone technology. With 4G, using the internet on your phone is even quicker, with speeds 5-7 times faster than 3G. If you have a 4G ready phone, but you’re not in a 4G area, you’ll still be able to use 3G.

What is 4G Calling?

Some phones support 4G Calling (also called Voice over LTE or VoLTE). 4G Calling lets you make clearer voice calls using our award-winning 4G network. If 4G Calling is available, you can just dial the number you want to call like normal. You can check 4G Calling coverage with our coverage checker.

Cellular network

The radio network used to send and receive calls and messages, and use the internet.

O2 Wifi

A fast, free wifi service available to everyone. You just download the app, and you’ll be connected to O2 Wifi whenever you’re in a hotspot.

Wifi

You can connect to the internet using wifi, to browse the web, download applications, or send and receive emails, without using your 3G or 4G data.

What is Wifi Calling?

Some phones can use wifi to make voice calls. Wifi Calling (also called Voice over Wifi or VoWifi), helps you make and receive calls even if you can't connect to the mobile network, like when you're on the London Underground. When connected to wifi, you can just dial the number you want to call like normal.

O2 Pocket Hotspot

A portable gadget that connects you and up to four other people or devices to the internet, when there’s O2 mobile data coverage. The O2 Pocket Hotspot automatically connects to our mobile network as soon as you insert a Pay & Go sim.