The measure would allow most workers to earn one hour of paid sick time for every 30 hours of work.
The council approved key changes to the bill, including expanding the definition of a family member for whose care one can take an earned sick day to include siblings.
Also, employees can enforce their rights under the law by going to municipal court if their rights are violated, and the Department of Child and Family Well-Being has the power to enforce the law.
"By broadening the definition of family and adding key enforcement mechanisms, the Newark City Council has strengthened a law that was already set to be one of the best in the nation," said Analilla Mejia, state political director of one of the state's health care unions.
Jersey City is the only other city in New Jersey with mandatory paid sick time.
Before the vote, workers and advocates representing a coalition of civic organizations, labor unions, and community leaders rallied at City Hall in support of the proposal.
They testified before the council about the public health and economic benefits of guaranteeing earned sick days for workers.
A statewide earned sick days bill has also been introducted in the New Jersey state legislature.