The comapany said that 533 people have been caught so far, with £17,600 levied against customers attempting to travel without paying.
In one case a businessman, who had taken 53 journeys over the course of a few months, had to pay £2,300 in missed fares and a £30 daily administration fee.
ScotRail said it recognises that it is relatively easy for passengers to get on and off trains without paying for all or part of their journey as only 17 of the 350 stations it operates across Scotland are equipped with ticket barriers.
However, the company warned passengers that the train operator’s CCTV cameras can prove where their journey began and ScotRail can then work out how much they owe.
Phil Campbell, ScotRail Head of Customer Operations, said: “A minority of our customers are taking advantage of the fact that due to coronavirus restrictions we are unable to put ticket inspectors on our trains or at most of our stations.
“While most of the population is sticking to the rules, these passengers are using the cover of Covid to avoid paying for their ticket.
“Revenue on the railway is down by around 90% due to the pandemic, so it’s vitally important that in order to give the best value to the taxpayer, we collect as many fares as possible.
“We have caught a number of repeat offenders and the message to anyone thinking of dodging their fare is simple. We are watching and we will catch you.”
ScotRail said that all of the passengers who have been caught so far have paid up since the alternative is prosecution which, if successful, would leave them with a criminal record.
The company said that there has also been an increase in the number of assaults, verbal or physical, on staff who ask customers to pay for their ticket.
It has held joint operations with British Transport Police to crack down on anti-social behaviour, focussing on specific areas across the network to provide additional support for ScotRail staff.