Rail passengers suffer 54 million hours of delays a year because of problems such as signal and train failures, research shows.
A study by the Rail, Maritime and Transport (RMT) union found that travellers across the country are being hit by daily delays mounting up to millions of hours every year.
The union published its report ahead of August's retail price inflation figure, used to calculate next year's rail fare increases. Forecasts predict inflation increasing to around 4%, said the RMT.
Speaking at the union’s annual conference in Exeter, general secretary Mick Cash said: "In a few weeks, passengers will be told that their fares are to go up in the region of 4% and the train operators will claim this further rip-off is necessary to fund investment.
"The reality of our fragmented, profit-driven industry is a network starved of the necessary investment leading to a scale-back of essential rail maintenance and renewals resulting in massive delays for passengers.
"These figures tell the real story of the actual impact of these delays, not only on passengers but also the economy as a whole."
A spokesman for the Rail Delivery Group, representing train companies and Network Rail, said: "Working together, rail companies have cut the number of incidents causing delays year-on-year, with record-high punctuality on parts of the railway.
"On an increasingly busy network each incident can have a greater knock-on effect, which is why we are delivering £50 billion-plus of improvements to make journeys better and more reliable, now and in the long term."