Transport for London (TfL) has invited tenders for a contract that could deliver Wi-Fi access to up to 120 tube stations.
The winning contract will be decided by the end of 2011, and TfL hopes the work will be completed in time for the 2012 Olympic Games.
The move follows a successful ongoing trial at Charing Cross Underground station carried out by BT Openzone.
The service would initially be made available at 16 tube stations where staff of TfL currently have access to Wi-Fi, and then extended to other stations.
Research carried out at the Charing Cross station suggests that over half of underground passengers believe Wi-Fi would make using the Underground a better experience.
The service would only be available in the station and on the platform, and is separate to the plans being assessed to provide mobile access on the tube itself.
"The rollout of Wi-Fi technology across platforms and public areas of our tube stations will finally allow Londoners to use mobile devices to pick up their emails, access social media sites while they traverse our subterranean network," said Boris Johnson, the Mayor of London.
"We are inviting companies to bid for this before next June, which would mean that people will be able to keep up to date with the British medal tally at the 2012 games when underground," he added.
TfL has confirmed that some information will be made available for free via Wi-Fi, such as travel updates. However, general access will be chargeable.
TfL could not confirm whether it would be looking for a single telecoms company to provide the service, or whether multiple companies could benefit from the tender.