Unison will hold a council-wide strike ballot in Southampton over proposed cuts.
The move came after at least five care workers in effect resigned their jobs this week by refusing to sign new contracts which included the withdrawal of unsocial hour enhancements.
Unison branch secretary Mike Tucker said fresh strikes by care staff, alongside any council-wide action on this and other issues, had not been ruled out and the union would consult its members next week.
About 240 Unison and TGWU members went on strike last week for the second time in the care workers’ dispute. Tucker said Unison had advised care staff to sign the new contracts to hold on to their jobs but a few refused to.
A council spokesperson said those who had not signed the new contracts were still welcome to do so, and it had compensated care staff for the withdrawal of the enhancements with higher basic pay.