Commuters in the South West are to face a rail fare rise of 3.6% from January, the TUC and rail unions warn today.
It means some season ticket prices are set to increase by more than £100 in 2015.
A season ticket from Plymouth to Exeter St David's could rise by £111 to £3,203 next year.
Figures show that rail fares will have increased by 24.9% from 2010 to 2015 and have risen faster than wages in every year.
Over the same period, average earnings have increased by just 10.7%.
Nigel Costley, Regional Secretary of the South West TUC, said that passengers are paying the price of privatisation.
He said: "It's grim news for commuters that they face yet another year of fare hikes above inflation, while their wages keep dragging behind inflation. It's time to stop private companies profiteering from our railways and to make sure that passengers and taxpayers' money is reinvested to improve our services. The only way to do this is to bring our railways back under public ownership."
The new-year rise is determined by July's RPI inflation figure and is being published today by the Office for National Statistics.
Unions forming the TUC's campaign group Action for Rail are holding demonstrations today at rail stations across the country.
Campaign for Better Transport public transport campaigner Martin Abrams said: "With people's wages stagnating and in some cases falling, the expense of taking the train to work has become a huge part of living costs.
"If the Government doesn't put an end to above-inflation fare increases quickly, ordinary commuters will be priced off the train and could be forced into agonising decisions such as moving house or quitting their jobs."
Passenger Focus surveys show that only 45 per cent of rail passengers believe that the services they use provides value for money.
In 2012/13 train companies received a total £1.3 billion in direct subsidies through franchise receipts and a further £3.9bn in indirect subsidy through investment in Network Rail services. In return, train operating companies paid back £1.2bn in franchise payments to the government. They made £172 million profit and paid £204 million to shareholders.
