9am in Chicago is 4pm in Zürich

Zürich is 7 hours ahead of Chicago. Chicago runs on America/Chicago (UTC-5); Zürich runs on Europe/Zurich (UTC+2). The difference is measured right now; it can shift by one hour during daylight-saving-time transitions.

Both Chicago and Zürich observe daylight saving time, but their transition dates are not identical. Chicago shifts between CST (UTC-6) and CDT (UTC-5); Zürich shifts between CET (UTC+1) and CEST (UTC+2). The difference between them stays close to 7 hours across most of the year, with short mismatch windows around each city’s transition when the gap briefly widens or narrows by an hour.

Standard 9-to-5 business hours in Chicago and Zürich overlap for roughly 1 hour a day. That window lands at 09:00–10:00 in Chicago and 16:00–17:00 in Zürich. Teams with real-time coordination needs anchor cross-city calls inside it: long enough to cover handovers, short enough that it forces crisp agendas. Outside that window, async is the default — shared docs, recorded updates, and scheduled follow-ups rather than live meetings.

When planning recurring meetings across Chicago and Zürich, pin them to one city’s local time rather than UTC or the other city’s clock. That way, the meeting time stays stable for the person anchoring the schedule, and the other side absorbs the one-hour drift during DST transitions. The alternative — a meeting pinned to the non-DST city — means the DST city sees the meeting time “move” twice a year, which is how recurring calendar invites end up at 7am on someone’s calendar in October.