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Guide

Scheduling meetings across time zones without the mess

Most cross-zone scheduling problems are not arithmetic problems. The maths takes ten seconds. The difficulty is agreeing a slot that is reasonable for everyone, and then keeping that slot correct through two daylight saving transitions a year. This guide covers both.

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Find the overlap before you propose a time

Start by working out the genuine overlap between the working days involved. London and New York share about four hours: 2pm to 6pm in London is 9am to 1pm in New York. London and Mumbai share about four and a half. London and Sydney share nothing at all during standard working hours, which means somebody is taking the call outside them.

Once you know the size of the overlap, the approach follows from it. A large overlap means you can simply pick a time. A narrow one means the overlap should be protected for anything that genuinely needs both parties live, with everything else moved to writing. No overlap means someone is making a sacrifice, and the only fair answer is to rotate who.

The second half of the problem is durability. A time agreed in February between London and New York moves in March, because the US changes its clocks three weeks before the EU does. The fix is procedural rather than mathematical: agree the slot once, put it in a calendar system, and let the software re-render it for each person. An email saying "every Tuesday at 3pm" is ambiguous the moment it crosses a border.

Key facts

London–New York overlap

About four hours, 2pm to 6pm UK time.

London–Mumbai overlap

Roughly four and a half hours in the UK afternoon.

London–Sydney overlap

None during standard working hours in either city.

The 8am and 5pm rule

Meetings before 8am or after 6pm local time get cancelled far more often.

Transition weeks

Late March and late October are when transatlantic slots silently move.

Rotation beats fairness policies

Alternating who takes the awkward slot works better than any fixed rule.

How to get it right

1

Map the working days

Write both in the same reference zone and see where they cross.

2

Pick inside the overlap

Choose a slot that is inside normal hours for everyone if one exists.

3

Send a calendar invitation

Never agree a recurring time as plain text in an email.

4

Review after each transition

Check recurring invites in late March and late October.

Questions people ask

Rotate it. If one side always takes the 10pm call, that side quietly disengages within a few months. Alternating between an early start and a late finish spreads the cost.

Keep reading

Daylight saving explained

Which countries change their clocks, when they do it, and why the same two cities can be five hours apart one week and six the next.

UTC, GMT and Zulu time

What UTC actually is, how it differs from GMT, why aviation says Zulu, and when the distinction matters.

Why abbreviations are ambiguous

IST means three different things, CST means three more. Which abbreviations are ambiguous and what to use instead.

Plan a meeting across zones

The meeting planner shows the working-hours overlap for several cities at once.

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