Jet lag from London to Sydney: what to expect

How long does jet lag last from London to Sydney?

Your clock will adapt the long way round: later each day, not earlier.

Unaided, eastward shifts settle at around a day per time zone: about 11 days for this one. S6 S7

This plan targets 8 days.

That's what the plan aims at, not a promise — bodies vary.

For this trip that's 3 days sooner than the unaided estimate, on the effort level that fits around a working day.

On night one, the afternoon you land, the plan's bedtime is 13:25, early by Sydney's clock, and it moves later night by night, reaching 23:00 by night 9.

Studies of aircrew point the same way: after large shifts, westward adaptation runs roughly 50% faster than eastward S6 S8. It's why the plan goes the long way round here.

What does the plan say for a typical London to Sydney flight?

Departs

23:15 London time

Lands

07:30 Sydney time +2 days

In the air

about 21h 15m (estimate)

Light, landing day

12:25–13:25 Seek bright light (delay shift)

Keep it dim, landing day

21:25–23:25 Avoid bright light (sunglasses / dim room)

Last caffeine, landing day

05:30 on the plane

Caffeine after landing

21:25–10:30 landing night into the next day

First night's sleep

13:25–21:25 the afternoon you land

Eastbound long-hauls tend to land in the morning, so this example lands in Sydney at 07:30, leaving London at 23:15 the day before, after about 21h 15m in the air.

The flight time is our estimate for a nonstop from the distance, and the trip is set in January. It's the default traveler from the calculator: usually asleep 23:00 to 07:00, no melatonin, Real Life effort.

Flying this far east, you land two calendar days after you leave.

That's longer than any regular nonstop flight, so in practice this trip has a stop. For a trip with connections, the calculator takes your first departure and your final arrival.

In July the gap is 9 hours, not 11, because London and Sydney change their clocks in opposite halves of the year.

The plan puts about 8 hours of sleep on board, from 12:10 Sydney time. You're awake again before you land.

The day before you fly, the plan keeps your morning dim, 07:00–09:00 London time, and the sun is up in London by about 07:58 in January, so plan on sunglasses for the commute.

Your last coffee on the plane is at 05:30 Sydney time. After you land the plan opens caffeine again at 21:25, until 10:30 the next day: at 21:25 your body thinks it's 10:25 in London, its morning, and the plan keeps you up through the night on purpose.

January is summer in Sydney, with about 14 hours of daylight. In January the sun is up in Sydney from about 06:04 to 20:07, so the 12:25 light step on landing day is daylight. Outside is the easy way to get it.

What helps after flying east to Sydney?

Because the plan moves your clock later, the light advice for westward trips applies here, even though you fly east: light before your body's low point, which usually means bright light in the evening and staying up a little later S1. Bright light first thing in the morning works against you. East vs west explains the mechanism, and the plan's light steps above already follow it.

And the flight home from Sydney?

Sydney to London is the same 11 hours the other way, westward. It's the easier direction: about 8 days unaided, and the plan targets 7. Jet lag from Sydney to London has the details.

More routes from London

• London to New York
• London to Boston
• London to Miami
• London to Chicago
• London to Los Angeles