The bill, which was approved 6-3, would affect 625 members of the staffs of the council and Mayor Dave Bing, The Detroit News reported. Members of the mayor's staff said they would get one unpaid day off every two weeks.
The measure is expected to save $250,000 a month. Officials say savings would be even greater if the unions representing the bulk of city workers agree to furloughs.
Under Michigan law, the city faces the appointment of an emergency financial manager if officials cannot get the deficit under control.
Last week, the council approved higher co-pays on health insurance for city workers. But that wouldn't begin until October with savings coming in the next fiscal year.
The council also froze payments to the pension fund for non-union employees.