Passengers do not feel the train companies are "on their side", according to a survey of thousands of rail travellers.
Many passengers do not trust their train company to provide a good day-to-day service nor do they trust them to be truthful, fair or communicate well, the survey from rail customer watchdog Passenger Focus found.
London and south east England train companies inspired the least trust.
Involving 4,000 online interviews with rail travellers, the survey looked at how passengers trusted their service and what trust they put in their relationship with their train company.
Trust in the service involved de livery of the day-to-day service including five factors - punctuality/reliability, value for money, problem resolution, helpful staff on trains and helpful staff at stations.
Passengers agreeing on at least four of these measures were deemed to be showing a positive attitude while those agreeing on four or more measures were counted as holding a negative attitude.
On this basis, only three companies - Grand Central, Merseyrail and ScotRail - got positive marks, with Southern, First Great Western and Southeastern the furthest into negative territory.
Trust in relationship also involved five factors - being truthful, acting with honesty and integrity, building long-term relationships, treating customers fairly and communicating well with them.
On the same basis as the trust-in-service category, the only companies getting positive marks were Grand Central, Virgin Trains, Merseyrail, Chiltern and ScotRail, with Southern, Southeastern and Northern Rail getting the most negative marks.
But when it came to trusting a train company's judgment, with categories including having high principles and doing the right thing even when no-one was looking, only one company - Southeastern - fell into negative territory, with Virgin Trains top of this particular trust table, followed by Merseyrail and Grand Central.
Passenger Focus concluded: "To build greater trust with passengers, it is important not only to deliver a punctual and reliable service but also to build a stronger relationship with passengers, this being based on communicating openly and honestly.
"Most TOCs (train operating companies) can also increase satisfaction by focusing on passenger engagement, as customers do not currently feel that TOCs are 'on their side', acting with their interests at heart.
In particular, there is the potential to improve satisfaction by increasing the amount of TOC communication and being proactive, communicating with openness and transparency, particularly when things go wrong."
Launching the survey, Passenger Focus chief executive Anthony Smith said: "There is much that train companies - and governments - can do to improve trust. It is important for train companies to get the basic service right ahead of everything else.
"Then building on closer relationships with their passengers is important. One way is through high-quality communication. Passengers should feel that train companies are 'on their side'. We believe these issues should become part of new franchises.'"
Michael Roberts, director general of rail industry body the Rail Delivery Group, said: "Passengers are at the heart of what we do and we know that we must keep improving, driving up the quality of services to respond to their needs.
"This survey gives everyone in the industry a clear indication of what is working well and where it can do better. We will continue efforts to improve, particularly in communicating with and providing information to passengers.
"Improvements over the last 15 years have helped to transform our railway into the safest and fastest growing in Europe, with newer trains and more services."
The survey comes just days before the announcement of July's RPI inflation figure, on which next January's commuter fare rise is based.
Mick Cash, acting general secretary of the RMT transport union, said: "This survey does not surprise us in the slightest. Why would people trust private train companies whose only objective in life is to hack back staffing and services to the bone while whacking up fares for the travelling public in the name of pure and unadulterated greed?
"Passengers are set to get hit with another inflation-busting fare increase when the figures are announced next Tuesday, while the private operators are laughing all the way to the bank."
Transport Minister Robert Goodwill said: "Thanks to Government investment, more than £38 billion will be spent over the next five years to maintain and improve the railways.
"This is bringing more trains, more seats and more services. We are doing our bit, but the industry needs to work hard to inspire trust among their customers who expect a reliable service that offers value for money."
Shadow transport secretary Mary Creagh said: "This report is the latest evidence that David Cameron has failed to stand up for passengers struggling with the cost-of-living crisis, who have endured inflation-busting fare rises of 20% since 2010.
"Commuters in the South East have been particularly let down by incompetent ministers, who failed to introduce smart ticketing and agreed poor value franchise extensions after the West Coast fiasco.
"A Labour government will cap fares on every route, roll out smart ticketing and drive through the biggest reforms of the railways since privatisation, delivering a better deal for passengers and taxpayers."