How to schedule meetings across time zones without the 2am surprises
Find the overlap windows, survive daylight saving changes, write times nobody can misread, and share the early starts fairly.
Scheduling meetings across time zones is easy right up until it isn't. A client in Sydney, a colleague in Manchester and a partner in Singapore can all agree to 'Tuesday at nine', and each of them can mean a different moment. Add daylight saving changes that happen on different dates in each hemisphere, and a regular call can quietly drift an hour without anyone noticing.
This guide gives you practical overlap windows for common UK, Australia, New Zealand, India, Singapore and US combinations, explains the daylight saving traps, and shows how to write and rotate meeting times so nobody is always the one on at dawn. For the wider team side, see how to schedule team meetings more efficiently.
What makes scheduling across time zones tricky?
Three things cause almost every cross-time-zone mix-up: the size of the gap, daylight saving, and ambiguous wording.
The gap is not fixed
Many places change their clocks, and the northern and southern hemispheres do it in opposite directions on different dates. The UK moves from GMT (UTC+0) to BST (UTC+1) on the last Sunday in March and back on the last Sunday in October. New South Wales, Victoria, the ACT, Tasmania and South Australia move forward on the first Sunday in October and back on the first Sunday in April. Queensland, Western Australia and the Northern Territory do not use daylight saving. New Zealand moves to NZDT (UTC+13) on the last Sunday in September and back to NZST (UTC+12) on the first Sunday in April.
The result: London and Sydney are 9 hours apart in the UK summer, 11 hours apart in the UK winter, and 10 hours apart for a few weeks around each changeover. The US changes on different dates again, so London and New York are usually 5 hours apart but only 4 for a few weeks in March and around the end of October.
Some zones are not whole hours
India is on IST (UTC+5:30) all year with no daylight saving, and Adelaide is on ACST (UTC+9:30) or ACDT (UTC+10:30). Half-hour offsets catch out anyone doing sums in their head.
Words mean different things
'EST' can mean US Eastern or, informally, Australian Eastern. 'Tomorrow morning' from Brisbane may still be today in London. Even 'AEST' is often written in summer when Sydney is really on AEDT.
The fix is a simple system
- Know the typical overlap windows for the places you work with.
- Check the offsets for the actual meeting date, not today's.
- Write times with the city or zone named, and give the other person's time too.
- Rotate inconvenient slots for regular meetings.
Booking tools help, but check how yours displays times to visitors and state your own time zone clearly on your booking page.
Why getting time zones right matters
A missed meeting because of a time zone slip feels worse than an ordinary no-show. The client got up early or stayed late, waited on a video call, and heard nothing. It chips away at trust in a way that is hard to fix with an apology email.
Time zone mistakes are also expensive in quieter ways. Each 'Is that your time or mine?' email adds a round of back-and-forth. Regular calls that land at 7am for the same person every week wear people down, and they start declining, joining tired or sending a deputy. For client-facing businesses, that can mean slower decisions and lost work.
There is a wellbeing angle too. If you serve clients in Australia from the UK, or the other way round, it is easy to let early and late calls spread across the whole week. Deciding in advance which windows you offer, and sticking to them, protects your evenings. Our guide to avoiding meetings outside business hours covers that side, and if you choose to open a few out-of-hours slots deliberately, see how to accept appointments outside business hours without burning out.
Finally, clarity helps your reputation. A confirmation that says '9:00 GMT (London) / 20:00 AEDT (Sydney)' looks organised and leaves nothing to interpret. What goes in that email is covered in our guide to what to include in an appointment confirmation email.
Benefits of a clear time zone routine
Fewer missed meetings: everyone turns up at the same moment because the time was written unambiguously.
Less back-and-forth: known overlap windows mean you can propose a workable time first go.
Fairer regular meetings: rotating slots shares the early starts and late finishes.
No daylight saving surprises: checking changeover dates keeps recurring calls from drifting.
Better wellbeing: set windows stop international calls creeping across every evening.
A more professional impression: clients see you have thought about their day, not just yours.
How to schedule meetings across time zones in 7 steps
List where everyone actually is — Write down each attendee's city, not just their country. Australia alone has several time zones, and Brisbane and Sydney differ for half the year.
Find the overlap window — Map each person's working hours onto one timeline and look for the hour or two where they overlap. If there is no overlap, decide who stretches and by how much.
Check offsets for the meeting date — Look up the time difference for the date of the meeting, especially in March, April, late September, October and early November when clocks change in different places.
Propose two or three options — Offer a small number of times inside the overlap, or use a date poll so everyone can mark what works. This beats open-ended 'When suits you?' emails.
Write the time in every relevant zone — Name the day, date, time and city or zone for each main group, such as 'Tuesday 3 November, 9:00 GMT (London) / 20:00 AEDT (Sydney)'.
Rotate inconvenient slots for regular meetings — If a weekly call has no comfortable time for everyone, alternate between an early slot for one side and a late slot for the other, and tell people the pattern.
Recheck recurring meetings around clock changes — Put a reminder in your calendar a week before each changeover to confirm your recurring international calls still land where people expect.
Common time differences and overlap windows (UK view)
| Feature | Typical difference | Easiest overlap |
|---|---|---|
| UK to India (IST) | 4.5 hours (BST) or 5.5 hours (GMT) ahead | UK morning is India afternoon |
| UK to Singapore (SGT) | 7 hours (BST) or 8 hours (GMT) ahead | UK early morning is Singapore afternoon |
| UK to Perth (AWST) | 7 hours (BST) or 8 hours (GMT) ahead | UK early morning is Perth afternoon |
| UK to Sydney or Melbourne | 9 to 11 hours ahead | UK 7 to 9am is Sydney late afternoon or evening |
| UK to Auckland | 11 to 13 hours ahead | UK evening is Auckland next morning |
| UK to New York | 5 hours behind (4 for a few weeks) | UK afternoon is New York morning |
| UK to Los Angeles | 8 hours behind (7 for a few weeks) | UK late afternoon is LA morning |
| Sydney to Singapore | 2 hours (AEST) or 3 hours (AEDT) behind | Most of the working day |
Best practices for cross-time-zone meetings
Name a city alongside the time zone, such as 'Sydney time', so daylight saving is handled for you.
Use the 24-hour clock or am/pm consistently, and always include the day and date.
Keep international meetings short and focused, as someone is usually outside their best hours.
Record decisions in writing afterwards so people who could not attend can catch up.
Set your booking page availability in your own time zone and state that zone clearly on the page.
Use a date poll for group meetings across three or more zones rather than proposing times by email.
Keep a small reference note of offsets for your regular contacts and update it at each clock change.
Common time zone mistakes
Writing 'EST' and leaving people to guess whether you mean New York or Sydney.
Assuming the time difference today will be the same on the meeting date.
Treating all of Australia as one zone, or forgetting Queensland does not use daylight saving.
Always scheduling the regular call at your comfortable time and making the same person dial in at dawn.
Forgetting that a morning meeting in Australia may fall on the previous calendar day in the UK or US.
Doing half-hour offsets for India or Adelaide in your head instead of checking.
Example: a Brisbane research studio with London and Singapore clients
Take a four-person user research studio in Brisbane with a client team in London and a partner agency in Singapore. They hold a weekly project call on Tuesdays.
Brisbane is on AEST (UTC+10) all year, and Singapore on SGT (UTC+8) all year, so Singapore is always two hours behind Brisbane. London is the moving part: 9 hours behind Brisbane during BST and 10 hours behind during GMT.
Until the UK clocks go back on the last Sunday in October, they alternate two slots:
- Week A: 5:00pm Brisbane, 3:00pm Singapore, 8:00am London.
- Week B: 6:30pm Brisbane, 4:30pm Singapore, 9:30am London. The Brisbane team stays a little later so London gets a gentler start.
After the UK moves to GMT, the same Brisbane times would put London at 7:00am and 8:30am. So the studio shifts both slots an hour later in Brisbane:
- Week A: 6:00pm Brisbane, 4:00pm Singapore, 8:00am London.
- Week B: 7:30pm Brisbane, 5:30pm Singapore, 9:30am London.
Because the later Brisbane slots eat into the team's evenings, they agree to cap the call at 45 minutes and give the Brisbane attendees a later start the next morning.
For one-off client calls, they use a date poll in Calenix to find a time, and every confirmation names all three cities. Illustratively, if a missed call used to cost two hours of rework across three people, avoiding one a month saves six hours. For clients further east, see our guide to scheduling software for New Zealand businesses, and for Singapore partners, scheduling software for Singapore businesses.
FAQ
Frequently asked questions
Across every zone
Find a time that works, wherever your clients are
Use Calenix availability rules, buffers and date polls to offer sensible international meeting times and confirm them clearly.