Rail season tickets could be 10% cheaper by 2017 if train services were run by the public sector instead of private firms, according to new research.

A study by Action for Rail found that savings of £1.5 billion could be made over the next few years if lines were brought back under public control.

Commuters would benefit from "massive" savings if money was recouped from the amount privatised rail operators give to shareholders, said the campaign group.

Several contracts are up for renewal over the next few years, including the Northern, West Coast, South Eastern, South Western and Wales & Borders, offering the chance of returning them to the public sector, it was argued.

Around £520 million could be saved in shareholder dividends over the next few years, it was claimed.

Action for Rail said commuters on the UK's privatised railways could be spending more than twice as much of their salary on rail travel as passengers on publicly-owned railways in France, Germany, Spain and Italy.

A day of action is being held today at more than 40 stations throughout the UK, including Liverpool Lime Street, Glasgow Central, Nottingham and Portsmouth, as part of the Action for Rail campaign.

TUC general secretary Frances O'Grady, who chairs Action for Rail, said: "The UK has the most expensive rail fares in all of Europe. If services were run by the public sector, it would make a big difference to families and hard-pressed commuters, who have suffered year after year of wage-busting fare increases under privatised rail.

"This report highlights once again the huge cost of privatisation to taxpayers and passengers. Money that could be spent on making journeys cheaper is instead being siphoned off into shareholders' pockets and wasted on bidding and other franchising costs.

"The case for an integrated rail network under public ownership is overwhelming."

A spokesman for the Rail Delivery Group, which represents Network Rail and train operators, said: "The figures from Action for Rail should be taken with a large pinch of salt. Compared to the late 1990s, train companies are paying five times more money to government, largely because of phenomenal passenger growth on Britain's railway, helping to fund big investment in better services.

"Increases to season tickets are regulated by government and operators offer a range of fares to suit the needs of different passengers, including some of the cheapest fares in Europe."