Passenger satisfaction with ScotRail has "significantly declined" to its worst level since 2002, watchdog Transport Focus announced today.
The proportion of customers who were happy with the train operator's service slumped to 83 per cent in the latest independent official survey carried out last autumn.
This compares to 87 per cent in spring last year, and 90 per cent in autumn 2015, watchdog Transport Focus said.
It compares to Scotland-London operator Virgin Trains East Coast scoring 91 per cent - its best figure for three years.
Transport Focus said ScotRail's rating had "significantly declined" in the latest twice-yearly National Rail Passenger Survey.
The figures will come as a further blow to ScotRail, whose punctuality is still below acceptable levels, four months after ministers ordered an improvement plan.
Transport Focus said the figure was last as low as 83 per cent in autumn 2002, when ScotRail was run by National Express.
It also fell to that level in spring 2007, under FirstGroup, but the watchdog said it normally compare autumn with autumn results and spring with spring.
The results are the first to assess current operator Abellio's performance like-for-like - with autumn 2015.
The spring 2015 survey was completed before the firm took over from FirstGroup in April that year.
However, ScotRail's rating was still two points above the British average of 81 per cent in the survey.
Virgin Trains' west coast services scored 90 per cent, while fellow cross-Border operators CrossCountry and TransPennine Express were on 84 per cent.
ScotRail's least happy passengers were in Strathclyde, where 81 per cent were satisfied, compared to 85 per cent on inter-urban routes, 89 per cent on other urban routes and 90 per cent on rural routes.
A total of 1,357 passengers in Scotland were questioned between September and November.
The period covered a train breakdown in Edinburgh in November which forced the cancellation of 225 other services - one tenth of ScotRail's daily timetable.
Transport Focus chief executive Anthony Smith said: “These are disappointing results and a departure from ScotRail’s previous good performance.
Sadly, punctuality – which drives passenger views of the railway - has fallen six percentage points.
“Increased passenger numbers are putting extra pressure on the rail network both in its day-to-day operation and during rebuilding.
"Improvements and investments to the railway to cope with the growth and attract new passengers to rail are welcome.
“Meanwhile, ScotRail Alliance’s performance improvement plan needs to deliver better outcomes for passengers: trains arriving on time, fewer cancellations and carriages of the right length.”
The biggest fall in satisfaction was in how ScotRail deals with delays, a chronic Achilles heel for the operator for more than a decade.
Just 38 per cent of those polled were happy, a fall of 13 points on autumn 2015 and five points on spring 2016.
Other big falls in satisfaction were in train toilets, station ticket offices, station staff helpfulness and parking.
Ticket prices were among passengers' biggest bugbears, with only 49 per cent happy on inter-urban routes, and 55-75 per cent elsewhere.
Scottish Conservative shadow transport spokesman Liam Kerr said: “The customer satisfaction rates are hardly surprising given the recent treatment of passengers.
“It’s been clear for some time now that commuters are fed up needing to part with their cash for train services that are so often delayed or overcrowded.
“ScotRail and the SNP can release as many apologetic statements as they like, but, until services see significant improvements, commuters will continue to voice their dissatisfaction.”
Scottish Labour transport spokesman Neil Bibby said: "Today's survey confirms Scotland's commuters think ScotRail's performance has gone downhill since the SNP handed the contract to Abellio.
"Passengers are fed up with delayed, overcrowded and cancelled trains. ScotRail’s performance simply isn’t good enough.
"ScotRail will soon be under new management, but ultimately it is down to SNP transport minister Humza Yousaf to fix the mess the SNP has made of Scotland's rail network."
A spokesman for the Scottish Government's Transport Scotland agency, which controls the ScotRail franchise, said: “This is clearly a disappointing set of results for ScotRail, especially given the excellent customer feedback received in previous surveys and the high score from their first year.
"It is, however, important to recognise that since this survey was undertaken, a performance improvement plan has been introduced, which is starting to deliver results for passengers.
“Given the evidence gathering for this report coincided with a number of high-profile incidents and challenging upgrades to Scotland’s rail network, it’s perhaps not surprising customer satisfaction has fallen."
"However, overall passenger satisfaction remains above the GB average, and many people will soon see the benefits of a significant investment package with new and better trains and a more reliable service.
“That’s not to say some of this feedback is acceptable, far from it.
"We note that actions are already underway to address some of the main areas highlighted for improvement, and look forward to seeing further progress in the weeks and months ahead.”
ScotRail Alliance managing director Phil Verster, who announced last Friday he was quitting to lead a new rail project in England said: “Everyone who works on Scotland’s railway will be disappointed by these results –we always want our customer satisfaction to be going up.
"However, they come on the back of a difficult year for our customers.
"Operating a busy and complicated network is challenging at the best of times – and we are doing so during one of the largest investments in modernisation since Scotland’s railway was built in Victorian times.
“There is no alternative, though, to doing the work.
“The decision to invest in the railway’s future has been put off too many times and it is in the best long term interests of passengers that we get on and do it.
"It is then our job to do whatever we can to keep people moving during this work and to better communicate when things go wrong and explain why they go wrong.
"When we brought in our performance improvement plan, we said that we wanted to make sure that we were doing everything we could to transform the railway for tomorrow, while bringing about better performance today.
"I believe that we are making good progress, but there is much to do.
“The latest round of statistics has shown our punctuality and reliability is improving and bucking the national trend.
"That this has happened while we are still carrying out all of the work to deliver a new, more modern railway is down to the hard work, every day, of the 7,500 people who work for the ScotRail Alliance.
“This year, all of that improvement work will start to deliver results.
"The new faster, longer, greener trains that will deliver more seats and shorter journeys are currently being tested in Scotland ahead of their introduction later this year.
"In the months that follow, we will see more new trains, more services and improvements at more of our stations.
"This is exactly what customers want and it is what we are all working hard to deliver.”
Full report: http://www.transportfocus.org.uk/research-publications/publications/national-rail-passenger-survey-nrps-autumn-2016-main-report/