At its peak, three tickets a second were being given away – amounting to more than 10,000 per hour.
The free tickets were available on routes across the country, including journeys linking Scotland’s ‘seven cities’, as well as the scenic routes to Fort William and the Kyle of Lochalsh.
Rob Shorthouse, ScotRail Alliance Communications Director, said: “Our million pound ticket giveaway is proving to be hugely popular. Our website suppliers told us that the first hour of the giveaway was more like the first hour of Glastonbury tickets going on sale. It was just incredible.
“We are building the best railway that Scotland has ever had. We are just delighted that so many people have taken up our offer to have a day out in our beautiful country on us.”