The boss of rail operator GNER has admitted that customers often find it difficult to find the cheapest fares on his company's website.
GNER says it is trying to make finding cheaper fares easier
Chief executive Christopher Garnett said customers had to "hunt" for less expensive fares when using the site.
"You have to have patience," he told members of the House of Commons transport committee. "It's not easy."
The East Coast main line operator's boss said it was often easier to find cheap fares on budget airline websites.
Mr Garnett, who was giving evidence on fares to the transport committee, told MPs that GNER was attempting to make finding cheaper tickets easier for his company's customers.
But he warned that it could take about a year to introduce any changes.
Gwyneth Dunwoody, Labour's chair of the committee, said the ticketing system used across the UK rail network was "absolutely chaotic".
But Transport Minister Derek Twigg said: "I don't accept that it's an absolutely chaotic system. I think it is complex. It's not such a terrible system that it's driving passengers away."
"It is clear from the number of people using the railways that prices are not deterring passengers - it's a more effective service than it was."