Making schools pay to appeal students’ exam results risks turning the system into a postcode lottery, with grades questioned only by schools that can afford it, education leaders have warned.

This year the Scottish Qualifications Authority (SQA) is to introduce a new results service to replace the old appeals system. The move has been broadly welcomed, with many agreeing that the old system was used too widely by schools. Last year the SQA received 67,000 requests - meaning that about 7 per cent of exam entries were appealed. Fewer than half the appeals were successful and the process cost the body almost pound;800,000.

But with Scotland already grappling with a major curriculum and examination overhaul, the timing of the new scheme has been criticised.

Concerns have also been raised about who will meet the new costs introduced under the scheme. In some councils, the fees - which range from pound;10 to pound;40 per script - will be paid for from central budgets, but in others it will be up to schools to foot the bill out of their devolved budgets.

Ken Cunningham, general secretary of School Leaders Scotland, said he supported the introduction of the charges but was against schools paying them.

“If individual schools have to pay, that could lead to inequalities in the system because some schools would be able to afford it and others would not. That would be unfair,” he said. “We have to watch carefully that youngsters are not deprived simply because of where they find themselves.”

Scottish government guidance on who should foot the bill was urgently needed, said the Scottish Conservatives’ young people spokeswoman, Liz Smith. “With the introduction of the new National exams it’s inevitable that there will be more requests for marking reviews this year,” she said. “I’m just worried that if schools get the bill that will act as a disincentive when these decisions should be taken based on academic merit.”

The Scottish Parent Teacher Council expressed fears that the new system could result in cash-strapped schools passing the cost for reviewing exam papers on to families. Although the council was “broadly supportive of the changes”, many parents would be “surprised”, “taken aback” and “annoyed” if appeals were less widely used than in the past, said Eileen Prior, the group’s executive director.

In the past, the SQA has criticised schools for wasting its time and resources with too many speculative appeals. The system was originally intended as a safety net for exceptional cases but in recent years has become widely used. Under the new system there will be two options: the exceptional circumstances consideration service and the post-results service.

The first of these is free and is to be used by schools in cases where they believe, for example, that a candidate has suffered because of bereavement or illness. Schools will be able to submit a wider range of evidence than in the past to support these claims.

However, if a school is concerned about a candidate’s result and wants to ensure that no errors were made during marking, there will be a charge if the grade remains the same once checks have been carried out.

The costs will range from pound;10 for a “clerical check” to pound;39.75 for a “priority marking review”. An SQA spokeswoman said that how those costs were paid for was a matter for schools and local authorities to decide themselves.

“Schools and colleges are in the best position to gauge if a candidate did not perform to expected levels. We expect requests for clerical checks andor marking reviews to be made only if the school or college is confident that this is the case,” she said.

Edinburgh and Glasgow city councils and Borders council said they had yet to reach a policy decision on who would meet the cost of the new charges. However, it was likely that in Glasgow schools would use their devolved budgets to pay for unsuccessful review requests, the city’s director of education Maureen McKenna said. She added: “Our schools would not allow an inequity to arise and neither would we.”

In Fife, the cost would be covered centrally, a spokeswoman for the council said.

Bruce Robertson of the Association of Directors of Education in Scotland (ADES) said: “The ADES position is clear: we would not want to see any pupil disadvantaged and if there are good, well-thought-through grounds for a review then the school should go ahead, but the days of mass speculative appeals on grades are over.”