The feasibility of running sleeper trains between central Scotland and Thurso is being investigated by a public transport body.
The Highlands and Islands Transport Partnership (Hitrans) has suggested the service could be used by visitors to Caithness and the Orkney Islands.
Hitrans has had discussions with Serco, which runs sleeper services between London and Fort William and Inverness.
However, it said another operator may be interested in the new service.
Hitrans spokesman Frank Roach told BBC Radio Scotland: "This will be an entirely standalone operation separate from the existing Serco Caledonian sleeper operation."
He said discussions with operators could begin once the logistics of running the service were understood.
Potential users of the sleeper could be tourists who head to Caithness each year to take ferries from Scrabster, near Thurso, and in and near John O'Groats to Orkney.
Mr Roach said: "We do know there are 300,000 people who cross the Pentland Firth to go to Orkney. That is quite a serious amount of people."
Peter Strachan, managing director of the Caledonian Sleeper, said: "We look forward to seeing the outcome of Hitrans' feasibility study into extending the Caledonian Sleeper service to Caithness, although any decision on this would be made by the Scottish government."