The CSIRO found a shift from road to the Inland Rail could cut freight transport costs by up to $213 million a year.

Horticulture would be the biggest benefactor, saving up to $99.21 per tonne.

Croppers could save $48.87 a tonne, livestock transport costs could drop by 9 per cent while processed food transportation would be reduced by $57.82 a tonne.

The report also predicted a $62 per tonne (31 per cent) reduction for regional intermodal freight to and from major metropolitan centres and ports.

Deputy Prime Minister and Infrastructure Minister Barnaby Joyce said the savings justified the $14.5-billion project, which is due to be completed by 2027.

"Inland Rail gives us the greatest opportunity for boosting economic development in regional areas, which is why we are delivering the project as quickly as possible," Mr Joyce said.

"Reducing freight costs for businesses and industries along the route means they can expand and hire more Australians, helping regional economies grow into the future.

"Shifting freight from road to rail will drive down the cost of transporting goods and commodities to ports and better facilitate the sale of products, like coal, that underpin our standard of living."

It is estimated Inland Rail would take 200,000 trucks off the roads each year, or 150 B-doubles for each train between Melbourne and Brisbane.

Finance Minister Simon Birmingham said it would help to provide freight companies with more competition.

"CSIRO's modelling shows how Inland Rail could slash transport costs for more than 90 commodities across Australia," he said.

"This highlights the significance of building a national freight network that gives producers and businesses better access to domestic and international markets at competitive prices."