Nearly one in five free schools operating at under two-thirds of the pupils they need to fill in seven years

Route 39 Academy, now renamed as Atlantic Academy, is among those free schools operating well under their capacity

Approaching one in ten mainstream free schools are educating fewer than half the number of pupils that they should be doing, if projections that they will be full to capacity within seven years of opening are to come to fruition.

Instead, 22 of them are operating with so many spare places that it will take at least 15 years for them to fill up at current rates.

Our new analysis of official DfE data appears to raise further questions about the economics of running a minority of free schools not only on low pupil numbers for several years as they build up year groups, which is the policy’s general pattern, but also, in some cases, lower pupil year numbers within each year group than they have space for.

It also raises the issue of more struggling free schools possibly having to close in 2018-19.