Trains will move to a reduced timetable from Monday with a focus on providing public transport for key workers during the coronavirus pandemic.
ScotRail said changes to the timetable are necessary as availability of its staff as well as those at Network Rail Scotland have been affected, while there have been changes to customer demand.
It said reducing the number of trains in service will give more time for extra cleaning on trains and in depots, as well as more targeted cleaning at stations.
The Scottish Government said the decision to reduce services has been taken to protect services for essential workers and allow vital freight trains to continue to operate.
It said the changes will be similar to a Sunday service with some additional first and late last trains for key staff, while off peak passenger services may be reduced further depending on demand.
Transport Secretary Michael Matheson said: “Following discussions with rail industry partners, passenger services will see a reduction as we continue to tackle the coronavirus.
“We know that rail provides an important service in moving passengers and goods around the country – however we will reach a point where travel is reduced to essential journeys only.
“Moving to a reduced timetable will not only help ensure some passenger services continue to run, it will enable freight to be prioritised so goods and emergency supplies such as medicines can be moved around the country.
“Constructive dialogue has been held with rail unions with discussion focused on protecting rail staff while they make a significant contribution to keeping passengers and goods moving as much as possible in these challenging circumstances
“We are also investigating ways to provide proportionate relief to operators, while also ensuring contractual incentives remain to mitigate the impact of doing so.”
Mr Matheson added that any changes to rail franchise contracts, including funding mechanisms, will be made “in the best interests of the public and business communities”.
David Simpson, ScotRail operations director, said: “We are facing an unprecedented challenge on Scotland’s Railway and the revised timetable will help to provide a critical service for the key workers across the country.
“Our own people are absolutely committed and are working flat out on the frontline to help keep the country moving, while also keeping themselves and customers safe.
“The railway has an important role to play during this crisis and we will work closely with the Scottish Government to do all we can as the situation develops.”
The Rail Freight Group (RFG), the representative body for rail freight in the UK, said it welcomes the support of the Scottish Government and Scotland’s Railway in ensuring freight services are prioritised on the network.
Alex Hynes, managing director of Scotland’s Railway, said: “We are facing an unprecedented challenge on Scotland’s Railway and revising the timetable will help to provide a critical service for the key workers across the country.”
Avanti West Coast has also announced it will be operating a reduced timetable from Monday.
For passengers in Scotland, there will be one service per hour to and from London and Glasgow which will call at regular stations, including Oxenholme and Penrith, and additionally at Crewe.
A small number of services will call at Lockerbie and Motherwell at key times.