More than three-quarters of train passengers are unaware of their compensation and refund rights when trains are delayed or cancelled, according to a report by rail regulators.
A survey and study groups revealed over 75% of rail passengers "do not know very much" or "nothing at all" about what they are entitled to when services are disrupted.
From the Office of Rail Regulation (ORR), the report also showed that 74% of the study participants said that train companies do "not very much" or "nothing at all" to proactively provide information about compensation when there are delays.
Only around 20% of the passengers said information on compensation following delays was readily available and around half said they were not particularly confident they could even find the information if they looked for it.
The ORR also found that there was uncertainty as to whether a claim would be successful and confusion around how long it took to make a claim and not knowing that compensation was paid in vouchers.
The ORR survey also revealed that only 11% said they "always" or "usually" claimed compensation when delayed, with 15% saying they rarely claimed and 68% never claiming.
This year, the ORR will oversee the development of a code of practice on provision of ticket retail information, which will be in place by the end of 2014.
The code will provide clarity on what information passengers can expect from their train companies, including information on the different types of fares, any restrictions that apply, and key terms and conditions, such as compensation and refund rights.
ORR chairman Anna Walker said: "Passengers must be at the heart of the rail industry and are crucial to its growth and success.
"We want to see that passengers are treated fairly, receive the quality of service they pay for, and when this is not the case, can hold their service providers to account."
She went on: "Our research suggests that simply putting information on a website, or only making it available on request, is not sufficient to help consumers be aware of or exercise their rights.
"Britain's rail industry needs to be more transparent and proactive in providing information. This includes data on passenger compensation."
The report was compiled from a survey of 1,000 passengers, plus telephone interviews with 100 passengers and four focus groups.
David Sidebottom, acting chief executive of rail traveller watchdog Passenger Focus, said: "When trains are delayed or cancelled, it is important that passengers are made aware of their rights to a refund or compensation."
"It is of concern that as many as 75% of rail passengers 'do not know very much' or 'nothing at all' about their rights."
He went on: "This is a problem that needs addressing. The top issues raised by passengers contacting us regularly include train delays, refund conditions and levels of compensation."
Among improvements Passenger Focus would like to see are providing compensation in cash rather than vouchers and enshrining compensation regime improvements in new rail franchises being introduced over the next few months.
Rail minister Stephen Hammond said: "I am determined that passengers have the best possible experience on our railways so I welcome the ORR report.
"Our new franchising agreements are ensuring that more-generous compensation schemes are in place for passengers and it is essential they know how to claim. I will continue to push operators to do all they can to make sure passengers are fully aware of their rights."
Michael Roberts, director general of industry body the Rail Delivery Group, said: "Compensation has become increasingly generous and easier to apply for in recent years.
"Latest available figures show that in the space of a year, there was a £3 million rise in Delay Repay (available if delays hit 30 minutes) money paid to passengers, despite punctuality hovering near record levels according to government-set measures."
Mr Roberts added: "Passengers can claim or find out about compensation on trains, at stations, online, through social media and via smartphone apps.
"But this research makes clear that there is more to be done to ensure that passengers know their rights. Operators are keen to respond to customer feedback and will continue to work with the ORR and others to raise awareness and confidence."
Which? executive director Richard Lloyd said: "It is absolutely right that it should be made easier for rail passengers to complain. We found that 10% of passengers had cause to complain on their last train journey, yet three-quarters of them didn't. With satisfaction so low, it is important consumers know their rights and find out if they are entitled to compensation.
"Which? is encouraging passengers to formally complain to their train company and to share their experience on our website, which will form a dossier of customer complaints to be presented to each train company."