Caledonian Sleeper has been fined £177,000 for failing tough quality standards in the first year that official inspections have carried penalties.
The overnight Scotland-London train service failed in 15 of 21 areas checked in the year to March.
However, it was not just aspects of the 40-year-old train fleet, due to be completely replaced by next month, which were below par.
Station lounges reserved for Sleeper passengers waiting to board were marked down despite £6 million of improvements.
They scored 73.6 per cent against a “benchmark” target of 95 per cent, including for broken light bulbs.
On the trains, seated coaches earned the lowest marks – averaging 65.8 per cent over the year against a target of 90 per cent. Sleeping cabins scored 73.2 compared to their 95 per cent target.
But there were 100 per cent scores for train heating and ventilation, staff and customer care, and lack of graffiti.
The inspections are made under the “service quality incentive regime” (Squire), which is the most stringent on Britain’s railways and also covers ScotRail.
Sleeper operator Serco has been checked monthly since it took over the service four years ago, but penalties were not imposed until 2018/19.
The operators are fined for failing to hit benchmarks, but paid bonuses if exceeded. The fines will fund improvements, which have yet to be revealed.
The Scottish Government’s Transport Scotland agency, which runs the inspections, said: “Penalties were set at a level considered appropriate, considering the age of the rolling stock inherited from the previous franchisee.”
It said the new trains “will improve performance against Squire on aspects such as lighting, train catering, berths and passenger information”.
Caledonian Sleeper managing director Ryan Flaherty said: “The Squire review shows there are improvements that can be made and we will be working with Transport Scotland to address any issues that it raises.
“We welcome this process as we are constantly looking at ways to improve the service we provide for guests, whether that is on board our trains or at the stations we serve.
“As we introduce our new carriages and retire our old fleet, we anticipate a major improvement in guest experience and fully expect that to be reflected in future performance figures.”