Workers who commute by train spend up to six times as much of their salaries on fares as European passengers on publicly owned railways, a study has revealed.
Action for Rail, a campaign by rail unions and the TUC, said some UK workers were spending 13% of their monthly wages on rail travel compared with 2% in Italy.
The research was published to highlight protests at more than 60 railway stations by campaigners and rail workers to mark the return to work after the festive break, with fares having increased at the weekend.
The analysis looked at a UK worker on an average salary who is spending 13% of their monthly wages on a £357.90 monthly season ticket from Chelmsford to London.
By contrast, the average amount of salary going on a monthly season ticket for a similar journey is 2% in Italy, 3% in Spain and 4% in Germany.
In France, which is the closest to the UK for cost, commuters still spend nearly a third less on season tickets than their counterparts in the UK, said the report.
A survey of more than 1,700 adults for the campaign group found that three out of five believed train services in the UK were poor value for money, with a similar number supporting public ownership.
TUC general secretary Frances O'Grady said: "It's hardly surprising that UK passengers think rail travel is bad value for money. They are shelling out far more of their income on rail fares than their counterparts in Europe.
"Years of failed privatisation have left us with exorbitant ticket prices, overcrowded trains and ageing infrastructure. Ministers need to wake up to this reality instead of allowing train companies to milk the system at taxpayers' and commuters' expense."
Rail, Maritime and Transport union leader Mick Cash said: "Today is national rail rip-off day when, along with the looming Christmas credit card bills, the British public awake to another kick in the teeth from the greedy private train companies. We would urge everyone to join with the trade unions to end the money-making racket on our rail tracks in 2016. "
TSSA general secretary Manuel Cortes said: "Profit made on passengers in the UK is not reinvested here, but repatriated to Germany, France, Belgium and Hong Kong to subsidise journeys of passengers there.
"We need a railway for the future - that means a publicly owned rail service operating in the interests of British passengers, with every penny made in profit reinvested in the railways or in cheaper fares for passengers."
Unite acting national officer for rail Hugh Roberts said: "European state-owned rail companies provide excellent services and cheaper fares as part of coherent national economic strategies. The UK Government's ideological reliance on the profit-hungry private sector has been a disaster - and the majority of the public wants the railways taken back into public ownership."
Aslef general secretary Mick Whelan said: "Taking the railways back into public hands is a popular policy. The vast majority of voters - Conservative included - are fed up with paying sky-high fares so the privatised train companies can take their slice. Commuters travelling into London from Kent and Sussex know their £5,000 a year season tickets would be much cheaper under public ownership."
Action for Rail said it looked at the price of monthly season tickets in five countries and compared them with figures for annual median earnings for 2014 based on OECD statistics.
:: Tabulated by: country, journey, distance in miles, monthly season ticket price, monthly median earnings, % of monthly median earnings
UK, Chelmsford-London, 29, £358, £2,745, 13%
Germany, Eberswalde-Berlin, 31, £95, £2,452, 4%
France, Etampes-Paris, 29, £234, £2,422, 10%
Italy, Cerveteri Ladispoli Rome, 29, £37, £1,929, 2%
Spain, Arenys de Mar Barcelona, 27, £56, £1,805, 3%