How bad is jet lag flying to London?

It depends where you start. From Sydney you cross 9 time zones travelling west, which typically takes about 6 days to shake off. From cities in a similar longitude to London there is little or no jet lag at all.

Is jet lag worse flying east or west to London?

Flying east — where you lose hours and have to fall asleep earlier — is generally harder than flying west, for the same number of time zones. The table above marks the direction of each route so you know which kind of adjustment to expect.

How long does it take to get over jet lag in London?

A common rule of thumb is one day of recovery per time zone crossed when heading east, and a little faster heading west. Bright light at the right time of day and adjusting your sleep before you fly both speed it up.

Jet lag when you fly to London

London is on Europe/London. How much jet lag you get depends entirely on where you start — how many time zones you cross, and in which direction. Travelling west is the easier direction. Stay up later than usual before you go and get evening light once you arrive.

Jet lag to London by departure city

From	Time zones	Direction	Distance	Flight (approx.)	Recovery
Sydney	9	← west	16,994 km	20½ hours	~6 days
Los Angeles	8	→ east	8,756 km	11 hours	~8 days
Tokyo	8	← west	9,559 km	12 hours	~5 days
Singapore	7	← west	10,855 km	13½ hours	~5 days
New York City	5	→ east	5,570 km	7½ hours	~5 days
Mumbai	5	← west	7,192 km	9 hours	~3 days
São Paulo	4	→ east	9,497 km	12 hours	~4 days
Dubai	3	← west	5,486 km	7 hours	~2 days
Paris	1	← west	344 km	1 hour	~1 day
Johannesburg	1	← west	9,070 km	11½ hours	~1 day

Distances are great-circle; flight times are rough nonstop estimates. Recovery uses ~1 day per zone east, faster west.

Beating jet lag in London

Jet lag happens because your body clock stays on home time for a while after you land. The bigger the offset between London and where you flew from, the longer it takes to catch up — roughly a day for each time zone when you travel east, and somewhat faster when you travel west, because it is easier to stay up late than to force yourself to sleep early.

A few days before you fly, nudge your sleep schedule toward London time — earlier if you are heading east, later if west. On arrival, get outside: daylight is the strongest signal for resetting your clock. Morning light helps after an eastward trip; evening light helps after a westward one. To see the exact current offset, check the current time in London.

Frequently asked questions

How bad is jet lag flying to London?: It depends where you start. From Sydney you cross 9 time zones travelling west, which typically takes about 6 days to shake off. From cities in a similar longitude to London there is little or no jet lag at all.
Is jet lag worse flying east or west to London?: Flying east — where you lose hours and have to fall asleep earlier — is generally harder than flying west, for the same number of time zones. The table above marks the direction of each route so you know which kind of adjustment to expect.
How long does it take to get over jet lag in London?: A common rule of thumb is one day of recovery per time zone crossed when heading east, and a little faster heading west. Bright light at the right time of day and adjusting your sleep before you fly both speed it up.