Virgin Trains has been accused of acting like the "Gestapo" after a businessman exploited a loophole to cut more than £250 off the price of his ticket.
Steve Morrissey, 32, the director of a software company, was accused of fare dodging after booking his 7.38am train from Lancaster to London on Tuesday for £93.
But he was accused of getting on the train at the next stop, Preston, 25 miles south, where the price is £350.
The father-of-one was left embarrassed as he was accused by ticket collectors on the train of getting on at Preston, ordered to buy another ticket or be fined and detained at Euston where British Transport Police were waiting.
Mr Morrissey, from Bispham, Lancs, said:
Mr Morrissey refused to buy another ticket and protested his innocence until CCTV was checked and showed him getting on the train at Lancaster as he had told train staff.
After the 40-minute delay while CCTV was studied he said he was given a hasty apology and allowed to go on his way - but by then had missed his business meeting in the capital.
Mr Morrissey said Virgin staff were cracking down on passengers after the big difference in ticket prices between Preston and Lancaster on the West Coast Main Line was publicised recently.
Another passenger claimed he was threatened with arrest for buying a cheaper single ticket from Lancaster to London, but actually getting on the train at Preston station.
Mr Morrissey said:
He was given an apology from Virgin Trains and initially offered half price tickets for his next journey before being offered two free first class return journey tickets.
An overhaul of Britain's rail fares is to be trialled to make it easier to buy the cheapest tickets after the Commons Transport Select Committee published a damning report which stated that "unfairness, complexity and a lack of transparency" in rail ticketing have been apparent for at least a decade.
Rail passengers faced with eye-watering fares are having to carry piles of different tickets to save money on their journeys.
A football fan last week received 56 separate tickets when he booked a split ticket between Newcastle and Oxford for an FA Cup match on Saturday - tweeting a picture of the deck of tickets laid out on his bed.