A flight from London (LHR) to Sydney (SYD) typically takes about 20 h 20 min. The return, Sydney to London, takes about 21 h 55 min. The distance is 17,020 km (10,575 miles) along the great-circle path.
Non-stop flights: Qantas has said it will launch daily non-stop Sydney–London flights from October 2027 using specially built Airbus A350-1000ULR aircraft, with flight times of up to about 22 hours. Until then every journey includes a stop (commonly in the Gulf, Singapore or Perth), so the total trip is longer than the direct-flying time shown here. Reviewed October 2026.
The jet stream, a fast river of air at cruising altitude, blows mostly from west to east. Flying London to Sydney you ride it, about 20 h 20 min; flying Sydney to London you fly into it, about 21 h 55 min. It is the same distance either way, which is why the westbound leg is usually the longer one.
Sydney is 10 hours ahead of London (standard time; the gap shifts by an hour for part of the year when only one of them is on daylight saving). Leave London at 10:00 and you land at about 16:22 Sydney time, the next day.
Sydney is 10 hours ahead, so your body clock has to move earlier. That is the harder direction: with no plan, expect about 10 days to feel properly adjusted. With a gap this large your body may adapt in either direction, so simply follow local time and light as soon as you land.
For two or three days before, go to bed and get up an hour earlier each day, and get bright light soon after waking. Even a partial shift helps.
Set your watch to Sydney time as you board. On a typical morning departure you land around 16:22 Sydney time, in daylight: sleep only if it is night in Sydney, drink water, go easy on alcohol, and then stay up until local bedtime.
Get outdoor light in the morning and avoid bright light in the evening for the first few days. Keep any nap under 30 minutes, and have caffeine only before noon.
General guidance, not medical advice. If you have a health condition or take medication, ask your doctor before changing your sleep routine.
At 17,020 km this is beyond the normal non-stop range of any standard airliner. The exception is the Airbus A350-1000ULR, a modified A350 with extra fuel capacity that Qantas is introducing for this route from October 2027.
| Aircraft | Approx. range | Estimated LHR–SYD |
|---|---|---|
| Airbus A320neo | 6,300 km | needs a stop |
| Boeing 737-800 | 5,400 km | needs a stop |
| Airbus A321LR | 7,400 km | needs a stop |
| Boeing 787-9 | 14,100 km | needs a stop |
| Airbus A350-900 | 15,000 km | needs a stop |
| Boeing 777-300ER | 13,650 km | needs a stop |
Distance is the great-circle distance between London Heathrow and Sydney Kingsford Smith. Time is that distance at about 830 km/h cruise, adjusted for the prevailing jet stream, plus roughly 35 minutes for taxi, climb and descent. It is a typical scheduled-time estimate, not a timetable: airlines publish their own, and daily winds, routing and air traffic can move a long flight by half an hour or more. Reviewed October 2026.
About 20 h 20 min from LHR to SYD. The return flight is about 21 h 55 min.
From London to Sydney it is typically about 20 h 20 min, covering 17,020 km.
17,020 km (10,575 miles, 9,190 nautical miles) in a straight line.
The jet stream blows west to east, so the eastbound flight is shorter than the westbound one. The distance is identical.
Sydney is 10 hours ahead of London in standard time.
Not yet. Qantas has said it will start non-stop flights from October 2027 using Airbus A350-1000ULR aircraft, taking up to about 22 hours. Until then, flights make a stop.
Typically about 10 days with no plan, and less if you shift your sleep and light exposure to local time.
Shift your sleep an hour earlier for two or three days before you fly, switch to destination time on boarding, sleep on the flight when it is night there, and get outdoor light in the morning after you land.
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