The daily service from Fort William will launch as planned on Monday 6 April, operators West Coast Railways (WCR) announced today.
The luxury Northern Belle train’s Mother’s Day lunch trip from Glasgow and Edinburgh on Saturday will also go ahead.
The decision was opposed by rail campaigners.
WCR said some passengers had cancelled their tickets, but bookings were “still quite high”.
A spokesman said: “There is currently no change to government advice for train travel within the UK, although we continue to monitor things.
“So this magical steam train won’t be hitting the buffers.
“But we are taking every precaution to ensure the health and wellbeing of both our passengers and crew.
“We are planning to carry on running the twice-daily service through some of Scotland’s most stunning scenery during the summer.”
Passengers who have already booked are being offered gift cards if they wish to change to another date over the next 12 months.
Managing director Jeanette Snape said cleaning measures would be stepped up and all train crew would be temperature tested before departure.
She said: “The health and wellbeing of out guests and crew is of paramount importance to us.
“Our train will undergo a thorough clean before departing our home depot by a team of experienced cleaners.
“Once out on the rails, the onboard team follow comprehensive opening and closing down procedures which involve wiping down all surfaces including tables, door handles and grab rails.
“Our lead and second stewards have accredited qualifications over and above mandatory requirements and have recently received infection control awareness training in response to the recent outbreak.”
However, the chairman of the Friends of the West Highland Lines campaign group attacked the move.
Doug Carmichael said: “Personally, I think this is a bad decision on the part of the operator.
“The close passenger confinement in the coaches (built in the 1960s) along with only one toilet per coach and old-fashioned surfaces combines to make it conducive to potential spreading of the virus very easily.”
National tourism agency VisitScotland would say only: “The situation in Scotland with regards to Covid-19 is developing every day.
“We’d recommend businesses follow the Government’s advice but at this stage, there are no restrictions to train travel.”
Bo’ness heritage line to stay closed
However, the Bo’ness and Kinneil Railway, near Falkirk, said it would not open for three months.
It said: “It is with regret that in light of the #covid19UK pandemic we will not be opening the railway or
Museum of Scottish Railways to visitors before the end of June.
“This includes the station buffet, gift shop, model railway and visitor trail.”