Referring to operations to clear the streets of Christmas waste, the city council said 1,753 tonnes of waste was collected at kerbside on 29 December.
It said voluntary redundancies meant there were now 275 union members taking industrial action as opposed to 370 at the beginning of 2025.
Councillor Majid Mahmood recently told the BBC that waste collections had improved in recent months, although recycling remained suspended, as it has been since industrial action began.
He said the council would also be recruiting staff for its new food waste collection service, which is set to be rolled out from June, alongside the previous recycling service.
“We’ve been negotiating with Unite now for 12 months and we’ve made multiple offers, fair and reasonable offers to Unite, all of which have been rejected,” he said.
Talks to end the dispute broke down early in the summer of 2025, with the council announcing in July it was pressing ahead with its restructuring plans.
But Unite said members are staying “rock solid” on their industrial action.
In a statement, the union said: “There will be no end to the strikes, until there’s a fair deal for Birmingham’s bin workers.”