The council now has a revised pay structure
A council is considering whether there are grounds for appeal after about 5,000 mainly female staff won their case for equal pay.
Unions have said the women, employed by Birmingham City Council, may be owed £30m in back-pay for bonuses paid only to certain male workers.
Solicitors have said the pay-out could be up to £600m following the employment tribunal.
It was too early to determine financial implications, the council has said.
Councillor Alan Rudge, cabinet member for equalities and human resources, has said the issue that was considered by the tribunal related to the old pay and grading structure.
He has said in 2007 the authority "took positive action to remove the inappropriate bonus schemes" and it had introduced a revised pay and grading structure which was in line with the Equal Opportunity Commission's equality guidelines.
Mr Rudge said: "Consideration is being given as to whether there are grounds for appeal on any aspects of the decision."
Many people were unhappy with the new deal, which unions said left some people £18,000 worse off.
About 3,000 council staff went on strike in 2008 over the new pay structure, which Unison has said still left women underpaid.
The union has said it was difficult to calculate the total amount the council would have to pay out as a result of the tribunal.
Unison general secretary Dave Prentis has said: "For too long Birmingham City Council has failed to live up to its responsibilities to pay these women workers fairly."
Brian Strutton, national officer of the GMB, has said women members in Birmingham "can now expect very substantial payouts indeed, probably worth £30m."
Stefan Cross, of Stefan Cross Solicitors, has said the tribunal case had originally been brought on the grounds of gender pay discrimination.
Having established that a discriminatory pay system had been used by the council, he has said everyone was now entitled to bring a claim, regardless of their gender.
He has said 90% of the people affected were women, but his firm had also won claims on behalf of up to 100 male clients, who were employed in roles that had traditionally been considered women's roles such as caring and cleaning.