Friday is the last day ScotRail commuters can take advantage of off-peak fares as a Government trial scrapping peak-time prices comes to an end after almost a year.
The Scottish Government previously concluded the costs did not justify continuing the trial.
Around £40m has been spent on the scheme, which began on October 2, 2023 in a bid to make transport more affordable while lowering emissions.
The end of the pilot scheme on Friday means that a peak return ticket from Glasgow to Edinburgh will nearly double to around £31.40 while a train from Glasgow to Dundee will cost £47.80.
An analysis published by ministers in August found the trial had had a limited degree of success in encouraging more people to travel by train and mainly benefited existing passengers.
Passenger levels increased by a maximum of around 6.8% but the scheme required a 10% rise to be self-financing.
The price rise will come as ScotRail’s temporary timetable, introduced due to a train drivers’ dispute, is set to continue until at least October 6.
Members of the Aslef union voted to accept the latest pay offer earlier this week.
Ministers have said they recognise many travellers will be disappointed at the return of peak rail fares but point out that other discounts are available.
However opposition parties and campaign groups have urged the Scottish Government to think again.
Jamie Livingstone, head of Oxfam Scotland, said: “The return of peak rail fares is a short-sighted and damaging climate dead-end that hits commuters and the climate alike.
“While rail passengers are punished, thousands of private jets continue to soar above Scotland, spewing unnecessary pollution, virtually without penalty.
“Scottish ministers must lift their eyes to the skies to find bold but fair solutions – such as a tax on private jets – to fund essential climate action, like green travel, investing in a fairer future for all of us.”
A Transport Scotland spokeswoman said: “The peak fares removal pilot was a welcome incentive over the last 12 months, saving many passengers hundreds and in some cases thousands of pounds during the cost-of-living crisis.
“The Scottish Government would be open to consider future subsidy to remove peak fares should UK budget allocations improve in future years.
“Ministers understand this will be disappointing for many rail users, particularly for those who cannot choose when they travel to and from work. That is why a 12-month discount on all ScotRail season tickets has been introduced, available weekly, monthly and annually.
“Prior to the pilot someone travelling between Edinburgh and Glasgow would have paid £28.90 for an anytime return. They will now pay £31.40 for an anytime day return, but with the 20% discount this reduces to £18.52 if they use an annual season ticket to travel at least four days per week, or £21.25 if using a flexipass for a return journey.”
Claire Dickie, ScotRail commercial director, said: “The peak fares trial may be coming to an end, but we are introducing new ways for customers to lock in great value on their regular peak-time train travel.
“From September 28, enhanced discounts with season tickets and flexipass mean customers can continue to save on peak-time rail travel.
“Whether you’re commuting daily or travelling frequently on the same route, we’ll continue to offer you great value on a safe, reliable, and green form of public transport.”
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