Phase 4 allows additional business to reopen with limited capacities and COVID-19 safeguards, and significantly more indoor activity, but Chicago will have some greater restrictions compared to other parts of the state.
Chicago had initially been set to move to Phase 4 on July 1, but with the number of new cases declining faster than the city expected, officials decided to go ahead with the next phase Friday.
Restore Illinois: 5-phase reopening plan by Governor Pritzker splits IL into 4 regions
"Under no circumstances should our move to stage four be confused with this crisis being over," Mayor Lightfoot said Monday.
Indoor seating at restaurants, museums and zoos, health care facilities, movie theaters, performance venues and summer camps will all be allowed to reopen in Phase 4.
"We're working on serving as many people as we can. Just be patient with us, but the light is at the end of the tunnel," said Ron Anderson, executive director of the Irving Park YMCA.
YMCA fitness rooms will open July 1, and lap swimming will be allowed starting July 15. All other facilities will reopen in August and reservations will be required.
"We really wanted to make sure that we allow, still allow our patrons and our members to be social distancing," said Denise Lam, executive vice president of YMCA of Metro Chicago.
All indoor businesses will be allowed to operate at 25% capacity, with a maximum of 50 people per space.
Outdoor gatherings can have up to 100 people.
Residents are asked to continue to follow social distancing and wear a face mask.
RELATED: Illinois Reopening: Phase 4 guidelines released by Gov. Pritzker
"We're hoping we can put everything that we need in place and be ready to open by October, because we need time to market," said Jackie Taylor, founder and CEO of Black Ensemble Theater.
"We do not want to go the way that we've seen other states, other cities," Lightfoot said. "We want to turn the dimmer switch ever so slightly, consistent with the public health data."
The city has released industry-specific guidelines for reopening businesses, which are available at chicago.gov/reopening.
The city has hit all the required COVID-19 health metrics, including averaging fewer than 200 new cases a day and having a testing positivity rate under 7%. Numbers that continue to improve could result in restrictions being eased even more.
But health officials still urged caution.
"Moving to Phase 4 does not mark the end of COVID-19. It marks the beginning of another step forward," said CHDPH Commissioner Allison Arwady.
Because of the city's higher infection rate, Chicago's rules are stricter than the rest of Illinois. Officials estimate that in a group of 50 people in Chicago, there's a 15% chance someone has COVID-19.
"When you think, go up to 25 and that probability goes up to 60 percent, this is why we are being cautious and prudent," Lightfoot explained.
Reopening Illinois: Chicago's Lakefront Trail, 606 Trail bike path reopen with COVID-19 restrictions
The state guidelines will allow for that 50% capacity as of Friday, although indoor gatherings will, just like Chicago, be restricted to 50 people or fewer. Face coverings and six-foot social distancing will still be required.
The mayor said conventions and sporting events with fans are not likely to resume anytime soon, and there is still no target date for reopening the beaches.