A Playbook for Scheduling Meetings Across Time Zones
Finding fair overlap windows, writing invitations that cannot be misread, and handling pairs with little or no shared workday.
Start from the overlap, not from your calendar
The instinctive way to schedule is to scan your own free slots and offer them. Across timezones this fails immediately, because your convenient Tuesday morning may not exist as working hours on the other side. Instead, compute the overlap first: take each participant's rough workday, convert both into one reference frame, and see where they intersect. London and Seoul, eight or nine hours apart, intersect only in London's early morning and Seoul's early evening — that narrow band is the entire usable space, and every proposal should start inside it.
If there are more than two cities, overlap shrinks fast. Anchor on the pair with the smallest intersection and fit everyone else around it, rather than optimizing for the majority and stranding one region at 3 AM.
Write invitations that cannot be misread
Every cross-timezone invitation should carry three things: the time with an explicit city ("18:00 Seoul / 10:00 London"), the date for both sides when they differ, and a calendar event created in a real timezone so each client renders it locally. The double notation looks redundant right up until it catches a conversion error before the meeting instead of after.
Avoid noon and midnight in written plans entirely — "12 AM Friday" is genuinely ambiguous to many readers. Write 11:59 PM, 00:00, or simply pick a different minute.
When there is no good overlap
Some pairs barely share a waking hour — US West Coast and India, Seoul and the US East Coast in winter. For those, a live meeting is a cost someone pays every single time. Rotate that cost: alternate which side takes the early-morning or late-evening slot, meeting by meeting or month by month. A fixed time that is permanently comfortable for one office breeds quiet resentment in the other.
Better still, question whether the meeting needs to be live. Status updates, reviews, and announcements move well through documents and recorded video, leaving the scarce overlap window for discussion that genuinely needs back-and-forth. Teams that ration their overlap this way hold fewer, better meetings.
Keep recurring meetings from drifting
A recurring series is only correct until the next daylight saving transition. Pin the series to one owner city, spelled out in the event description — "this meeting follows London time" — so everyone knows which side's wall clock is authoritative when the offsets shift in March and October. Participants in non-shifting cities like Seoul or Singapore will see their local slot move by an hour; that is expected, not an error.
Twice a year, when the transitions hit, spend five minutes confirming the next occurrence with the other side. It is the cheapest insurance in international work.