Hundreds of English schools previously rated “outstanding” have been downgraded by Ofsted after their first inspections in years.

More than 500 were visited in the last academic year after a clause was lifted that had made them exempt from regular reinspection.

Introduced in 2012, it meant outstanding schools didn’t need regular visits unless there were specific concerns – but that system ended two years ago.

The school’s watchdog said only 17% of the 370 schools it inspected in 2021-22 kept their outstanding rating.

It added that the schools’ average gap since their previous inspection was 13 years.

Amanda Spielman, Ofsted’s chief, said it showed “removing a school from scrutiny does not make it better”.

Some 62% of schools reinspected were demoted one level to “good”, while 21% were said to either “require improvement” (the third tier) or were “inadequate” (the bottom tier).

Ofsted said that while the falls seen in the reinspected schools might not reflect all exempt schools, the results were none-the-less “concerning”.

“A higher proportion now require improvement or are inadequate than is the case for all schools nationally, especially for the primary schools,” it said.

The watchdog must inspect all previously exempt schools by the end of July 2025.

“Regular inspection gives parents confidence in the quality of their child’s school,” Ms Spielman added.

“Exempting outstanding schools deprived parents of up-to-date information. It also left a lot of schools without the constructive challenge that regular inspection provides.

“The exemption was a policy founded on the hope that high standards, once achieved, would never drop, and that freedom from inspection might drive them even higher.

“These outcomes show that removing a school from scrutiny does not make it better.”