Moving freight from road to rail in Tasmania could save as much as $160 million over four years, a study has found.

The study, commissioned by state-owned TasRail, found that most of the savings would be made through reduced road accidents, pollution and road maintenance.

For example, in 2013-14 the use of rail over road saved $7 million in accident costs, $9 million in road maintenance, $9 million in operating costs to businesses and $1 million in environmental costs.

Over the next five years, the Government investment in rail is about the same as those savings but the report forecasts that beyond 2019, the savings will be substantially greater.

TasRail is hoping eventually the savings will far exceed the investments made.

CEO Damien White said the rail operator was aiming to double its market share to about 50 per cent of contestable freight.

"There's a lot more freight out there that's currently on road that could be on rail," he said.

"We're certainly starting to talk to the agriculture industry because we think there could be a market there for us."

The report suggests that target is achievable and Mr White said he hoped it attracted more industry players.

"The report's about a bit of a pitch to the rest of the industry to communicate what are the benefits of using rail in Tasmania."

The Tasmanian Freight Logistics Council believes there is room for the use of rail to grow, particularly in the mining sector.

Mr White said the report also justified the $120 million investment made by government to upgrade the rail network over the next four years.

"It substantiates the investment made to date," he said.

"There's no doubt there will need to be continued investment as we continue to grow our volumes but for the time being we've got more than enough money to go on with."