The explosion in demand for special educational needs (SEN) support is threatening English county councils’ ability to meet their legal duties.
The number of support plans they have to meet by law has risen by a half since 2014, the county councils say.
The 27 that responded to a County Councils Network survey of the 36 English councils overspent their 2018-19 SEN budgets by a total of £123m.
The government says its investment into these budgets is significant.
Since 2014, councils have had to support 19- to 25-year-olds with special educational needs, as well as those of school age.
And this is one of the reasons for a 48% rise in the number of plans setting out the care and support to which young people are legally entitled.
Councillor Carl Les said the 2014 changes had caused costs to spiral out of control.
“As this huge increase in demand is unfunded, the cost burden has come from other service areas,” he said.
“Counties already face a funding gap of £21.5bn over the next five years – and if we continue to overspend at the level we have done, it will break many of our budgets.
“Many councils in the future may be unable to set a balanced budget, whilst others will have to reduce other budgets further, which would run the risk of not being able to deliver statutory duties.
“It is clear that the current system is not working effectively when nearly two-thirds of councils nationwide over the past year are not reaching the expected level of service in their special educational needs departments.”