Nearly every state school in England is still likely to be converted into an academy despite the government’s recent U-turn over forced academisation, a thinktank has claimed.

Last week, education secretary Nicky Morgan announced she was abandoning plans to introduce legislation bringing about “blanket conversion of all schools”.

Instead, the government will introduce new legislation that will trigger forced academisation if a local authority is no longer able to financially support the remaining schools in its area, or if its schools fail to meet “minimum performance thresholds”.

Under its own calculations, the education thinktank CentreForum said that the new legislation could force all but 3,000 schools in England to convert.

That figure does not even include the number of schools that would wilfully apply to become an academy, the organisation states.

To make its predictions, CentreForum made two assumptions that:

• A local authority is unviable if less than half of pupils in the area attend local authority maintained schools;
• A local authority is “underperforming” if the performance of its maintained schools at either key stage 2 or key stage 4 is below the (current) national average for state-funded mainstream schools.

If the government used the same methodology, around 12,000 schools would be forced to convert under the local authority approach to school conversion.

Currently, 15,000 schools have yet to become academies, leaving just 3,000 under CentreForum’s analysis. Out of that number, around 640 schools are rated as outstanding.

The study states: “This ignores the growth that is likely to come out of schools choosing to convert or failing and being forced to become sponsored academies. This both directly and indirectly increases the number of academies - as more schools convert, more local authorities will become unviable on this definition. It could lead to a situation where the decision of an individual school has implications for the wider authority.

“Given the combination of voluntary conversion, academisation under the Education and Adoption Act and direction at local authority it is possible that full academisation (or very close to it) could be achieved without forcing schools one at a time.”

Want to keep up with the latest education news and opinion? Follow TES on Twitter and like TES on Facebook