SCOTRAIL plans to cut Sunday train services by half due to staff shortages caused by an ongoing pay dispute are “unacceptable”, a union has said.

The national rail operator confirmed it is planning to operate between just 50% to 60% of services scheduled on Sundays due to a shortage of drivers volunteering to work overtime.

It comes days after ScotRail introduced a new temporary timetable, with about 26% of Monday to Saturday services cut.

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But ScotRail said about half of its 1100 Sunday services will need to be cut to provide “certainty” to commuters.

The pay dispute comes as drivers’ union Aslef confirmed it was considering whether to ballot members on industrial action.

Meanwhile, the National Union of Rail, Maritime and Transport Workers (RMT) and the Transport Salaried Staff’s Association (SSTA) are also considering action.

A 9% pay increase offered by ScotRail in six stages over three years has been rejected, with many drivers also refusing to work extra overtime shifts in the meantime.

The offer would have been paid in a 2% increase across April in three years to 2026 as well as a further 1% rise in January in 2025, 2026 and 2027.

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In a statement to The Scotsman, ScotRail said: “We are planning to operate around 50-60% of services on Sundays, but this varies from week to week with special events and planned Network Rail engineering work.”

But Kevin Lindsay, Scottish organiser for Aslef, said: “The decision by ScotRail to half the service on Sunday is unsurprising, but still utterly unacceptable and unfair on passengers.

“If they are only running 50% of the service then they should be giving passengers a 50% reduction in their fares.”

He said the rail firm had failed “time and time again” to address the ongoing pay dispute which is reliant on voluntary working and compulsory overtime.

He added: “We have had many guarantees that this issue will be addressed but, sadly, there has never been sufficient progress made by ScotRail. This cut to Sunday services is a mess of ScotRail’s own making.

“If the Scottish Government wants ScotRail staff to volunteer their days off, then, they must address the pay dispute and instruct ScotRail to get back around the negotiating table and come to it with a credible offer that our members deserve.”

ScotRail has also previously said it is recruiting an additional 160 drivers but will still rely on some rest day and overtime working to deliver a “normal” timetable.

A Transport Scotland spokesperson said: “While train planning and staff rotas are operational matters for ScotRail, we fully expect any timetable to give the best reliability and availability for passengers and that changes are communicated well in advance to enable effective journey planning.

“We acknowledge the desire of rail unions to negotiate a fair settlement for their members.

“ScotRail, as a public body and the employer, has responsibility and the ability to negotiate within the limits of public sector pay metrics. However, as rail unions have been made aware, any offer beyond these requires Scottish Government approval at senior level following the appropriate process.

“We would encourage rail unions to continue meaningful dialogue with ScotRail, so that a mutually agreeable outcome can be reached as soon as possible.”