Rail passengers face fork ing out an average of eight per cent more for their tickets from the start of next year.

And some fares could jump by up to 13 per cent under a system used to calculate the average increase across each train operator’s routes.

An eight per cent hike would take the cost of a First Great Western standard class annual season ticket between Oxford and London from £4,104 now to £4,432 next January, when the rises come into effect.

Oxfordshire rail campaign groups said the rises placed an unfair burden on people.

But Transport Secretary Philip Hammond said they were the only way to maintain rail investment.

The increases are calculated under a formula based on the retail price index (RPI) inflation rate the previous July. Last month’s RPI figure, announced by the Government yesterday, was five per cent.

The Department for Transport then allows a further percentage rise on top of the inflation rate to allow for investment.

In recent years this was set at one per cent, but as part of its comprehensive spending review last autumn, the Government announced increases would be set at RPI inflation plus three per cent for 2012-14. It wants make passengers pay more of the costs of improving the railway.

Hugh Jaeger, spokesman for the Thames Valley branch of campaign group Railfuture, said: “Pound for pound, the economy gets more out of rail investment than it does from road spending, so it’s worth putting money into rail to protect passengers from inflation-plus rises.

“And road users also benefit from rail investment, as it reduces congestion.

“Switching an ever-increasing share of rail investment to passengers is wrong. There should be a fair spread of the burden between passengers and taxpayers.”

The Cotswold Line between Oxford and Worcester is due to reopen next week after completion of a £67m investment programme, reinstating 20 miles of double track to improve punctuality and allow extra trains to run.

John Ellis, chairman of the Cotswold Line Promotion Group that represents passengers, said: “It’s obviously an unreasonable increase, especially at a time when we want to maximise use of new services that will be running on the line.”

David Mapp, commercial director of the Association of Train Operating Companies, said: “We know that these are difficult financial times for many people. The Government has decided that many fares need to rise above inflation for the next three years to help pay for more trains, better stations and faster services. All additional money raised through the change to RPI plus three per cent will go straight back to the Government.”

Mr Hammond said: “Due to the scale of the deficit, our rail investments would simply have not been possible.

“I know this decision has not been popular, but I hope passengers will appreciate the improvements it allows us to make.”

  • What you'll pay

    ANNUAL standard class rail season ticket prices now and what the same tickets could cost from January next year, assuming the average eight per cent increase is applied:

  • Oxford-London: £4,104 now, rising to £4,432
  • Didcot Parkway-Reading: £1,508, rising to £1,628
  • Bicester North-London £3,780, rising to £4,082
  • Charlbury-Oxford £1,164, rising to £1,257 A passenger turning up at Oxford station in the morning rush-hour to buy an anytime day return ticket to London could have to pay £55 next January, up from £51 now.
  • COMMENT: Page 10