Smoking has been banned on First ScotRail sleeper services following calls from passengers.
Smoking is now banned on all of First ScotRail services
Smoking restrictions came into force across all of the company's services on Sunday.
The move came as First ScotRail embarked on a £1m upgrade of the Scotland to London route.
Commercial director Gordon Dewar said: "Having monitored public opinion we have responded to our passengers' desire for a smoke-free environment."
Improvements have also been promised on the sleeper service, including new toilets and seating.
Mr Dewar said: "Smoking will no longer be permitted on our Caledonian Sleeper service, which, along with the refurbishment, will provide a better overall journey experience for our passengers."