O2 and Three mobile customers are missing out on "free" full WiFi on the London Underground.
Virgin Media has signed a wholesale connectivity deal with Vodafone and EE to support their customers on its fibre network.
Virgin Media built the London Underground WiFi network in time for the Olympics, and it allowed passengers to get free WiFi connectivity throughout 2012.
From 2013 though only the existing WiFi portal offering Transport for London travel information, news and entertainment will be free to all passengers. But Virgin Mobile, Vodafone and T-Mobile and Orange (the two brands owned by EE) customers will be able to also get full WiFi access at no charge - including their email and access to websites outside the walled Underground portal.
Virgin says mobile users on other networks will be offered wider WiFi access from £2 a day, with other weekly and monthly packages being made available.
The service doesn't work in tunnels, just ticket halls, escalators, platforms and on trains while at platforms. While passengers lose WiFi signals between short hops on the Tube, customers on the Channel Tunnel can still keep connected on their 2G and 3G phones through a network deployment this year.
Over 70 London Underground stations are already WiFi-enabled and Virgin Media says another 20 Tube stations will be connected in December, with a further 28 stations "due to come online early next year".