Education watchdog Ofsted rated Calderdale Council’s adoption performance ‘inadequate’ in a report published yesterday.
It said that between 2011-14 children in Calderdale waited on average 742 days from going into care to being placed for adoption - 114 days longer than the national average.
Recent data suggests a further deterioration, with Calderdale children now waiting on average 746 days.
The council has been told it must find ways to speed up the recruitment of adopters.
The report said children’s services required improvement but are no longer rated inadequate.
Inspectors noted that the issue of child sexual exploitation is given a high priority in Calderdale.
Last year 2,340 secondary school pupils attended sessions to raise awareness of such abuse.
The report said there was “evidence of a collective determination to tackle child sexual exploitation.”
Ofsted said the Local Safeguarding Children Board also required improvement because documents such as minutes were not routinely put on its website.
“This lack of transparency means that the LSCB is not fully accountable, and limits the ability of children, parents and carers to monitor its activities and hold it to account.”
Councillor Colin Raistrick, Cabinet member for children’s services, said: “Although there is still room for improvement this (report) is very welcome recognition of all the hard work and dedication of the Children’s Services team and our partners.
“I am pleased with their comments about the work that we do to protect vulnerable children who are at risk of harm, how we work with families when they need help to get back on track and recognise that we are ambitious for the children who we look after.
“In particular I’m proud the inspectors highlighted that the children we look after are doing so well academically, with significantly more achieving five good GCSEs than similar pupils nationally.”