Birmingham City Council says 7,000 jobs must go in a bid to save £300m.
So far 1,500 staff have requested voluntary redundancy, meaning forced losses will be "significantly reduced," council officials have said.
Some £212m - 71% of the savings target - will be made in the 12 months from April this year.
The details were revealed in a document by the council, a Conservative-Liberal Democrat coalition. A final decision will be made in March.
The union Unison described the job losses as "devastating".
The council says the jobs will go over the next three to four years, with 2,450 going in the next financial year.
Councillor Mike Whitby, leader of Birmingham City Council, said: "Undoubtedly this has been one of the most challenging budgets to plan.
"Although, inevitably, there will be a focus on reduced spend across the public sector it is important to remember that more than £3.5bn is still to be spent on quality public services."
Birmingham is the UK's largest local authority. The city council has 18,993 full-time staff posts.
A consultation in November detailed plans to reduce staff numbers to 11,877 by 2014/15.
Unison's assistant general secretary Roger McKenzie said: "It's not just devastating news for people losing their jobs, but for the people of Birmingham.
"This is 7,000 people thrown into three to four years of uncertainty.
"Uncertain how they are going to pay their mortgage, their rent or put food on the table."