The city originally gave potential casino operators until August 23 to submit plans for the casino project, but the Mayor's office said that the deadline will be pushed back to October 29.
"This extension gives potential bidders more time to fully assess the Chicago casino opportunity, conduct additional due diligence, assemble more competitive bid packages, and explore financing opportunities," the Mayor's office said in a press release.
"This historic casino project stands to expand the economic vibrancy and strength of our city by bringing sustainable, good-paying jobs to residents from underrepresented backgrounds and creating a world-class casino resort that attracts visitors from all over," said Lightfoot.
"Extending the deadline for interested bidders will allow the city to collect as many robust, impactful and transformative proposals as possible. I look forward to seeing these bids roll in and working very closely with whichever team is ultimately chosen to develop Chicago's first-ever casino," he added.
The Mayor's office said that any plans for a Chicago casino complex should include a hotel with a minimum of 500 rooms, restaurants, shops, and entertainment venues.
The potential casino operator will be authorised to build a temporary gaming operation while the permanent facility is being designed and built.