A focused Ofsted visit revealed Warwickshire social workers assigned to deal with vulnerable children are still pressured by 'overly high caseloads'.
The visit to Warwickshire County Council's Children's Services took place in July 2018 - it came after a main Ofsted visit to the service last year which resulted in a 'requires improvement' rating.
Focused visits are a new scheme in which Ofsted performs specific inspections in between their main inspections - which take place every three years.
Inspectors reviewed the authority’s arrangements for children in need and those subject to a child protection plan.
They found children's services had not yet achieved the desired goal of reducing caseloads to its target of 15 per worker and, although the number had reduced since the last inspection, it was still in the mid twenties.
The report stated: "Pressure to manage overly high caseloads remains evident."
The target to reduce the burden placed on social workers came after the service's 2017 Ofsted report, which stated: "Some staff, including social workers and independent reviewing officers (IROs), have too much work... Consequently, some children experience delay and make slower progress."
A spokesperson for Warwickshire County Council said a 'concerted effort' to reduce the service's reliance on agency staff means social workers are experiencing a temporary increase on their workload.
Warwickshire councillor Jeff Morgan, portfolio holder for children’s services, said: “Warwickshire’s report is positive and it recognises the steps we have taken to develop good practice that puts the needs of children and families at the heart of all we do.
“We accept that our caseloads are currently high but expect to see a marked difference when around thirty new colleagues join the authority in the Autumn."
The Ofsted report noted there are a number of new social workers due to start in September and that may reduce the workload - although it stated the 'staffing profile' could be impacted by a high ratio of relatively inexperienced social workers.
Senior staff recognised this issue and have taken measures to create additional teams to mitigate any problems this may bring, the report added.
The report stated the county's children's services have made "some progress in the delivery of social work services since the last inspection".
It noted a new approach to working with children in need through a recognised model of working with families was beginning to have an impact and ensuring that families receive good quality, targeted and direct help.
A spokesperson for Warwickshire council said: "Whilst the outcome of the focused visit was broadly positive this has no impact on the council’s grading as ‘requires improvement’. This will remain in place until the next full inspection of children’s services expected at some point in 2019."
Click here to read the report in full.