Federated Farmers says the inadequate school boarding allowance is affecting regional growth because it's difficult to attract staff to remote areas.
The federation's president, Katie Milne, says so far no political party has offered to fix the problem.
"For rural folk there's a glaring omission in the education policies of all the political parties," she said.
"The boarding allowance for pupils from remote areas of $3200 hasn't increased for more than a decade."
Ms Milne says state schools are charging up to $15,000 a year.
"For a farm manager with three kids, boarding school costs can be half of their take-home pay," she said.
"This issue makes it more difficult to attract staff to work in remote areas, and is a stumbling block for regional growth."
Ms Milne says the ministry talked about a review last year but nothing happened.