The moves come after John Swift QC, the regulator, received the results of a survey his office commissioned earlier this year which tested how well the new privatised network delivers passenger information. He said that the exercise showed that passengers had been sold the wrong tickets.
Mr Swift recounted his own personal experience as evidence of consumer's frustrations to a conference of rail industry executives.
"I wanted to go to York. I got two different quotes from the National Telephone Enquiry Service. I then went down to the station and got another price from the ticket office.
``It may be anecdotal but if this happens to me then it will be happening to others," said Mr Swift.
Earlier this year, his office sent hundreds of investigators out to pose as passengers and identify the apparent failures of train operators to provide accurate and impartial information about fares.
More than 5,000 inquiries at booking offices and via passengers' phone lines were made by researchers to check how far sales staff provided information about alternative routes and ticket prices.
The results of Mr Swift's survey will be released in "weeks". The performance of operators were tested in eleven different "scenarios", where ticket clerks were asked for everything from simple cheap day returns to more complex advance fares.
"It should not come as any surprise to anybody that the railway is generally very good at selling simple products," said Mr Swift. But the regulator said transactions involving a first-class ticket or an Apex ticket scored less well. "Much less well in the latter case."
Mr Swift, earlier this month, warned that he would fine operators or even alter their licences if companies failed to comply with his wishes.
He also highlighted the "crazy" way that complaint figures were used by the industry.
"You get figures from the Central Rail Users Consultative Committee which say that complaints are down by a third. Then you get another set of figures from a regional committee which paints another picture," he said. The west coast main line receives more than 50,000 complaints a year - but consultative committees report the figure to be in the hundreds.
Rail companies were surprised by the tough words from the regulator. Chris Tibbits, a director of Virgin Rail who chaired the conference, said that he "would work with the regulator to resolve any of the problems he brings to the public's attention."Reuse content