Thousands of rail passengers will be charged extra or face changing their routes under new rules to be approved by the Rail Regulator, John Swift, at the end of this month.
Rail user groups are furious that Mr Swift appears to have broken a commitment to protect their interests and sided with the train operators.
The Association of Train Operators (Atoc) has drawn up a routeing guide for the industry's new private operators which defines what is an acceptable way to travel between two points on the rail network. Inevitably, the complex task of defining which journeys between Britain's 2,500 stations are permitted and which are not has led to anomalies. These will affect the regular routes used by thousands of travellers, who will face penalty fares or excess charges.
Atoc has sent the guide - which a rail insider who had seen it said was originally "so large you needed a wheelbarrow to carry it" - to Mr Swift for approval and it is due to be enforced from 30 September.
The new operators do not want travellers to exploit loopholes which may allow them to make longer journeys on the same ticket, or use tickets - which are sometimes cheaper though the journey is longer - to get off at intermediate stations. Mr Swift had promised in his annual report that he would not endorse a guide which restricted existing commonly used routes. However, draft copies of the guide suggest that many commonly used routes have not been included.
Phil Wilkes, spokesman for the Central Rail Users' Consultative Committee said: "There have been countless drafts of this guide and we are concerned that there may still be anomalies which restrict people's travel patterns."
Barry Doe, a timetable expert, said: "Mr Swift appears to have broken his promise not to restrict routes currently used by many people."
A spokeswoman for Mr Swift's office said: "If [people] send in a complaint about a route which the operator feels ought to be allowed, then they will be entitled to a refund if subsequently the route is allowed."
However, Keith Bill, of Save our Railways, which is planning legal action if the guide is not improved, said: "This is sheer lunacy and people will not do it as they won't understand it."
How passengers beat the system
The Reading trick: Travellers from the West and South-West will not be able to change at Reading to go to London Waterloo instead of London Paddington. This is likely to affect thousands of people in November when the Tube's Bakerloo line is closed for refurbishment.
The Swansea diversion: Passengers from Swansea to Norwich will be forced to go on the infrequent central Wales line to Shrewsbury and change for Birmingham and Norwich, rather than going on the more frequent Swansea to Cardiff trains and changing there for Birmingham and Norwich.
The York dog-leg: The route from York to London Euston via Manchester, used by people visiting the North West on the return leg, is scrapped.
Many travellers arriving at Waterloo will no longer be able to cross to Waterloo East for a free transfer to Charing Cross.
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