Network and service
Network upgrades, WiFi Calling, and troubleshooting network related issues.
Network coverageDiscover why the SMARTY network is so powerful.
Mobile and Broadband Estimated Maximum SpeedsThe estimated maximum speed that the SMARTY Network (powered by Three) will support.
What bandwidth and spectrum is available on SMARTY?Learn about the difference between 3G, 4G, 4G+, VoLTE, and L-Band.
Our policy on data shaping and network throttling
Free Wi-Fi on London UndergroundStay connected underground at over 250 stations
Coverage on the London UndergroundFind out more about network coverage on the London Underground
What is WiFi Calling?Here’s the lowdown on what Wi-Fi Calling is and why it’s great for keeping you connected
How do I use WiFi Calling?Everything you need to know about setting up and using WiFi Calling.
Which devices are compatible with WiFi Calling?To use WiFi Calling, first, you'll need a compatible mobile device.
My WiFi Calling is not workingSteps to help you troubleshoot WiFi Calling