Cumbria County Council is to appeal against an employment tribunal decision ordering it to compensate female workers employed on less favourable terms than men.
The GMB and Unison unions brought equal pay claims on behalf of 2,926 care assistants, cleaners and cooks.
An employment tribunal ruled in March that care workers and some other staff were entitled to pay rises and compensation of up to £60,000 each.
The council has earmarked £8.7m to cover the equal pay award, which is unlikely to be enough as unions believe the final bill could run to £50m.
Councillor Liz Mallinson said: “It’s of paramount importance that we say the county council is a good employer and will meet its obligations according to the law. But we have to use public money the best way possible.”