Remote and distributed teams have made international scheduling a daily reality for hundreds of millions of workers. Yet despite decades of globalization, scheduling a meeting across time zones remains one of the most reliably frustrating tasks in modern work life. Missed calls, confused attendees, and the dreaded "I thought it was 3pm your time" are universal experiences.
This guide covers the practical mechanics of cross-timezone scheduling: how to find overlap windows, how to handle DST transitions, which city pairs are easy versus nearly impossible to align, and the tools and habits that eliminate most scheduling errors.
Business Hours Overlap by City Pair
The first step in scheduling any international meeting is understanding how much overlap exists between standard business hours (9am–5pm) in each location. The table below shows the overlap for ten major city pairs — color-coded by difficulty.
| City Pair | Overlap Window | Hours | Difficulty |
|---|---|---|---|
| New York / London | 2pm–5pm GMT / 9am–12pm ET | 3h | easy |
| New York / Tokyo | None in business hours | 0h | hard |
| New York / Singapore | None in business hours | 0h | hard |
| London / Dubai | 9am–5pm GMT / 1pm–9pm GST | 8h | easy |
| London / Singapore | 9am–1pm GMT / 5pm–9pm SGT | 4h | moderate |
| London / Sydney | 9am–10am GMT / 8pm–9pm AEDT | 1h | hard |
| Dubai / Singapore | 9am–5pm GST / 1pm–9pm SGT | 8h | easy |
| LA / New York | 12pm–5pm ET / 9am–2pm PT | 5h | easy |
| Berlin / Singapore | 9am–1pm CET / 4pm–8pm SGT | 4h | moderate |
| Sydney / Tokyo | 9am–5pm JST / 10am–6pm AEDT | 8h | easy |
The Impossible Pairs: New York–Tokyo and New York–Singapore
Zero Business-Hours Overlap
Some city pairs have zero business-hours overlap. New York (UTC−5) and Tokyo (UTC+9) are 14 hours apart in winter. When it's 9am in New York, it's 11pm in Tokyo. When Tokyo opens at 9am, it's 7pm the previous evening in New York. There is no time that is business hours in both cities simultaneously.
The practical solutions for these pairs are:
- Early morning New York / Late evening Tokyo: 8–9am ET is 9–10pm JST. Tolerable for occasional calls, unsustainable as a recurring slot.
- Asynchronous-first workflow: Use recorded video updates, detailed written briefs, and shared documents. Reserve live calls for high-stakes decisions only.
- Rotating burden: Alternate who takes the inconvenient slot, so neither team always bears the cost.
- Overlap days: Schedule live collaboration during the few weeks per year when teams are in the same location for offsites or conferences.
The DST Scheduling Trap
The Transition Week Problem
Daylight Saving Time creates a particularly nasty scheduling trap for recurring meetings. Consider a weekly call between New York and London, set for "3pm London time / 10am New York time" in January:
- January–March 8: NY is UTC−5, London is UTC+0. Difference: 5 hours. Call is 10am ET / 3pm GMT. ✓
- March 9–30 (USA springs forward, UK hasn't): NY is UTC−4, London is UTC+0. Difference: 4 hours. The calendar invite still says 10am ET — but that's now 2pm London time, not 3pm. ✗
- March 31 onward (UK springs forward): NY is UTC−4, London is UTC+1. Difference: 5 hours again. 10am ET = 3pm BST. ✓
The three-week window between the US and UK transitions catches teams out every single year. The fix: use calendar tools that store meetings in UTC and display them in local time, rather than storing them as a fixed local time.
Six Best Practices for Cross-Timezone Scheduling
The "Golden Hours" for Global Calls
Best UTC Windows for Multi-Region Calls
If you need to schedule a call that works for multiple regions simultaneously, the following windows are the closest to universally workable:
| UTC Window | New York | London | Dubai | Singapore | Sydney |
|---|---|---|---|---|---|
| 07:00–09:00 | 2–4am ✗ | 7–9am ✓ | 11am–1pm ✓ | 3–5pm ✓ | 5–7pm ✓ |
| 08:00–10:00 | 3–5am ✗ | 8–10am ✓ | 12–2pm ✓ | 4–6pm ✓ | 6–8pm ✓ |
| 13:00–15:00 | 8–10am ✓ | 1–3pm ✓ | 5–7pm ✓ | 9–11pm ✗ | 11pm–1am ✗ |
| 14:00–16:00 | 9–11am ✓ | 2–4pm ✓ | 6–8pm ✓ | 10pm–12am ✗ | 12–2am ✗ |
✓ = business hours | ✗ = outside business hours | Times shown in winter (standard time)
Tools for Cross-Timezone Scheduling
Several tools make cross-timezone scheduling significantly easier:
- WhatTimeIsIt.blog Timezone Converter: Convert any time between any two cities with live DST awareness.
- WhatTimeIsIt.blog City Compare: See two cities' times side by side with full timezone and weather context.
- World Time Buddy: Visual overlap planner for up to four cities simultaneously.
- Calendly / Cal.com: Scheduling links that automatically convert to each attendee's local time zone.
- Google Calendar: Displays events in local time and supports multiple time zone display in the day/week view.
Check Current Times
Before scheduling your next international call, check the current local time in each city: