Rail fares have increased at double the speed of wages since 2010, research by trade unions suggests.
Fares have risen by 25% in the past six years, while average weekly earnings have grown by 12%, analysis by the TUC and the Action for Rail campaign shows.
However, the government said that wages were now growing faster than rail fares.
It comes as commuters are to find out how much regulated fares in England, Scotland and Wales will rise in 2017.
The increase will be linked to July's Retail Prices Index inflation rate, which will be confirmed at 09:30 BST.
June's RPI inflation rate was 1.6%.
The government has said previously that regulated fares will rise by no more than RPI for the rest of this parliament.
About half of rail fares are regulated, including season tickets on most commuter journeys.
Some off-peak return tickets on long distance trips and "anytime" tickets around major cities are also regulated.
At the beginning of 2016, the cost of regulated fares went up by 1% in England, Scotland and Wales. Northern Ireland is treated separately - in March, Stormont announced public bus and rail fares would not rise this year.
While the government sets the cap for the rise in regulated fares, unregulated fares, such as off-peak leisure tickets, can go up by as much as train companies like.
The study by the trade unions showed dividends paid to shareholders of private train companies have risen by 21% in the last year to £222m.
TUC general secretary Frances O'Grady said rail passengers were "paying more and getting even less", and called for rail services to be nationalised.
"Fares go up while trains remain overcrowded, stations are unstaffed, and rail companies cut the guards who ensure journeys run smoothly and safely.
"It's time for rail services to be publicly owned, saving money for passengers and taxpayers alike."
However, the government said that standards were improving, and that commuters were now getting a better deal.
"Wages are growing faster than train ticket prices thanks to action by the government and our commitment to cap regulated rail fares in line with inflation will save annual season ticket holders £425 on average in the five years to 2020," said Rail Minister Paul Maynard.
TSSA general secretary Manuel Cortes said private profit was being placed above rail safety.
"Our rail fares are already the highest in Europe and today's increases will only make that record worse," he added.
"It's time that ministers gave rail passengers a break and actually froze fares in real terms."
The union-led Action for Rail group said it was planning to stage protests at a number of stations in England, Scotland and Wales on Tuesday.
Meanwhile, Jeremy Corbyn has pledged to extend public ownership of the country's bus networks if he becomes prime minister.
Both he and his rival in the upcoming Labour leadership contest, Owen Smith, have said they would renationalise the railways if they won power.