England's largest councils have told Sky News they're facing a "simply unsustainable" funding crisis due to the soaring cost of transporting children with special needs to school.
More money is now being spent on taxis and minibuses for SEND (Special Educational Needs or Disability) pupils by county councils than on family, youth and sure start services combined.
School transport budgets are being described by the County Councils Network as "increasingly out of control".
Some even face future bankruptcy if expenditure on special needs school transport stays the same, without intervention, it said.
It is also warning some "discretionary services", such as libraries and recycling centres, may have to be cut.
A report by the Isos Partnership, released early to Sky News, predicts the cost of sending children with educational needs to school will top £1.1bn in the next five years.
That figure would mean costs tripling over a decade from £397m in 2018/19 to £1.1bn in 2027/28.
The number of pupils eligible for free school transport has increased by 120% in the same period from 58,000 to 129,000.
The increase in cost is driven by the "explosion" in the number of children receiving Education, Health and Care Plans (ECHPs), which set out support needed including transport.