True 24-hour Starbucks are rare: only 61 of Chicago's 186 stores qualify — that is 33% of the city. Most are inside airports, hospitals, or along major highways. If you cannot find one in Chicago, the nearest 24-hour location may be 30+ miles away at a major highway exit.
Overnight staffing and security costs make 24/7 operations expensive. That is why you see this format almost exclusively where there is captive overnight foot traffic — flight crews at airports, night-shift workers at hospitals, long-haul drivers at truck stops, casino guests. A standalone residential-street Starbucks almost never runs 24 hours.
Some "24-hour" stores pause briefly (2–4 hours) for deep cleaning, typically between 2 AM and 6 AM on one weekday. If you rely on a specific location for an overnight shift, call ahead to confirm the cleaning schedule. Mobile Order is disabled during those cleaning windows even if the app shows the store open.