Train companies are failing to offer the cheapest fares on their ticket machines, causing thousands of passengers to pay double the correct price.

Several companies in southern England are charging passengers more in this way but the problem is greatest at South West Trains (SWT), the operator exposed this week as having ordered guards to issue as many penalties as possible.

Families and other groups travelling together are particularly affected by the problem with the machines.

Last weekend SWT charged dozens of Falklands veterans on their way to London for the 25th anniversary of the islands’ liberation more than the cheapest fare available.

The companies have chosen secretly not to programme their ticket machines to sell the GroupSave fare, which is meant to be available to any group of three or four people travelling after the morning peak. Under GroupSave, when two adults buy tickets another two can travel free. Staff at ticket offices are obliged to sell the cheapest fare, including GroupSave, even if passengers do not specifically request it. But the law does not extend to machines.

WhenThe Timestried to buy return tickets from London to Weymouth for four people yesterday, the ticket machine charged £212.40 and the ticket office £106.20.

Passengers travelling alone are also unable to obtain the cheapest fares from machines for some morning trains on which those fares are valid. The fares can be obtained only from ticket offices. Only 44 of SWT’s 177 stations have offices open for at least 12 hours a day. Another 105 have part-time ticket offices and 28 have no offices.

SWT has put up signs telling passengers that they must buy a ticket before boarding and that they will be prosecuted if they try to pay on the train, even if there are long queues at machines and offices.

A SWT guard told The Times: “We are regularly finding groups of passengers who have been overcharged by the machines. There are no signs by the machines telling them they could save a lot of money by going to the ticket office.

“People used to be able to get on board and ask us for the cheapest fare. But now they are so terrified of getting a penalty fare that they pay whatever amount the machine says.”

He said that a group of 20 Falklands veterans travelling together last weekend had each paid £10 for their tickets from machines when they should, under GroupSave, have paid only £5. “We have informed our managers of the problem but they tell us to ignore it. They don’t care because the company profits from it.”

Passenger Focus, the rail passenger watchdog, said that it was making a formal complaint to SWT. Anthony Smith, the watchdog’s chief executive, said: “The mad scrabble for revenue is taking priority over the need to offer passengers the full range of tickets. Given the recent 20 per cent fare rises, it is very unfair not to give people a chance to obtain the discount to which they are entitled.”

After being presented with the evidence gathered by The Times, SWT said that it would consider reprogramming its machines to offer the GroupSave discount. A spokeswoman added: “We are looking at adding more options, but then we get advised that the machines are really complicated and people can’t use them.”

Explore UK News

• Crime News

• Education News

• Health News

• Scotland News

Times Recommends

• Oh no, Mr Darling: you have failed
• BBC survives dogfight over Kennel Club expose
• Where the Rosetta belongs can’t be set in stone