A quarter of secondary school parents say they've had to take out a loan or borrow from friends in order to meet back to school costs this year.
Research from Barnardos shows the average cost of sending a fourth class pupil to school is €320, rising to €972 for a student entering secondary school.
The charity's Back to School Survey of over a thousand parents has found half at primary level and two thirds at second level are worried about meeting the costs this year.
Barnardos' CEO, Suzannne Connolly says the notion that education in Ireland is free is completely untrue.
"Some of the parents we spoke to spend the summer worrying about the cost of sending their children back to school.
"What we're doing is we're calling on the Government to extend the free school books to secondary schools, to ensure that all schools provide a low cost uniform option, and to end voluntary contributions and maintain the increase in the back to school allowance."
