A high court case this week could put the council's funding for children's services at risk.
Rising court costs imposed by the Government are hitting councils across the country hard in the pocket, and Hillingdon is leading the fight for fairer funding.
Since May local authorities have had to cope with a 2,500 per cent increase in Judicial Care Proceedings court costs, which could lead to a £100,000 shortfall in Hillingdon alone.
Hillingdon has joined up with the councils of Liverpool, Leeds and Norfolk. The case will be heard in the High Court tomorrow (Thursday) and Friday.
Ray Puddifoot, leader of Hillingdon Council, said: "This issue could put funding for other children's services at risk, and we are not prepared to let that happen.
"By increasing the cost of these court proceedings, and not putting into place a fair allocation system for local authorities to meet these costs, some local authorities will be out of pocket and the extra costs will ultimately be met by local tax payers."
A victory would be the second High Court triumph in a matter of months for the council after it won a battle for a £4 million grant to deal with asylum seekers coming in through Heathrow Airport.
"This case highlights again the strong commitment this council has to ensure that we are receiving fair and sufficient funding from central Government to meet the costs they impose on our residents," said Mr Puddifoot.
The case will be supported by both children's charity the NSPCC and the Law Society.