Almost 3,000 workers at Birmingham City Council have won wage rises after successfully appealing against a controversial pay and grading review.
The local authority received nearly 6,000 formal objections when the new grading system left thousands of staff worse off.
Two years after the pay review was imposed, almost 5,000 appeals have been heard and 59 per cent were successful.
Most of those winning wage rises are home care assistants, community librarians, clerical assistants and neighbourhood office advisers.
The cost to the council so far is estimated at £9 million.
The figure is almost three times the £3.5 million the council estimated a year ago.
Council leaders say they always expected a large number of appeals would be successful and they have put money aside to pay the bill.
They blame trade unions for advising staff not to complete job evaluation forms when the pay and grading exercise was taking place, which resulted in many employees being allocated lower grades than should have been the case.
Sarah Dunlavey, head of city finance, said: “The financial impact of successful appeals is extremely difficult to assess, since it is affected by the individual’s previous pay levels, and the operation of protection and pay progression arrangements.”
About 800 appeals are still to be heard.