Time difference between Australia and the United States

Q: What is the time difference between Australia and the United States?

There is no single figure. the United States spans 6 of the offsets in this data, so the difference runs from 12 hours (Perth to New York) to 20 hours (Brisbane to Honolulu). Any converter giving one number for this pair has quietly picked a city.

12 hours to 20 hours, depending on the city

Why there is no single answer

Australia spans 2 different offsets in this data — Brisbane, Sydney and Melbourne at UTC+10, Perth at UTC+8; and The United States spans 6 different offsets in this data — New York at UTC−5, Chicago at UTC−6, Denver at UTC−7, Los Angeles at UTC−8, Anchorage at UTC−9, Honolulu at UTC−10. One number cannot cover 2 and 6 offsets, so any single figure for "Australia to the United States" is a choice of city — declared or not. That is why two sources can both be right and still disagree, and why the useful answer is the table rather than the number.

Every combination

From	To	Usual difference	Changes in the year
Brisbane	New York	14 hours behind	yes — also 15 hours
Brisbane	Chicago	15 hours behind	yes — also 16 hours
Brisbane	Denver	16 hours behind	yes — also 17 hours
Brisbane	Los Angeles	17 hours behind	yes — also 18 hours
Brisbane	Anchorage	18 hours behind	yes — also 19 hours
Brisbane	Honolulu	20 hours behind	no
Sydney	New York	14 hours behind	yes — also 16 hours, 15 hours
Sydney	Chicago	15 hours behind	yes — also 17 hours, 16 hours
Sydney	Denver	16 hours behind	yes — also 18 hours, 17 hours
Sydney	Los Angeles	17 hours behind	yes — also 19 hours, 18 hours
Sydney	Anchorage	18 hours behind	yes — also 20 hours, 19 hours
Sydney	Honolulu	20 hours behind	yes — also 21 hours
Melbourne	New York	14 hours behind	yes — also 16 hours, 15 hours
Melbourne	Chicago	15 hours behind	yes — also 17 hours, 16 hours
Melbourne	Denver	16 hours behind	yes — also 18 hours, 17 hours
Melbourne	Los Angeles	17 hours behind	yes — also 19 hours, 18 hours
Melbourne	Anchorage	18 hours behind	yes — also 20 hours, 19 hours
Melbourne	Honolulu	20 hours behind	yes — also 21 hours
Perth	New York	12 hours behind	yes — also 13 hours
Perth	Chicago	13 hours behind	yes — also 14 hours
Perth	Denver	14 hours behind	yes — also 15 hours
Perth	Los Angeles	15 hours behind	yes — also 16 hours
Perth	Anchorage	16 hours behind	yes — also 17 hours
Perth	Honolulu	18 hours behind	no

When the gap moves

22 of these 24 combinations change by an hour at some point in the year. Brisbane, Perth and Honolulu do not change their clocks; Sydney and Melbourne go forward on the first Sunday in October and back on the first Sunday in April; New York, Chicago, Denver, Los Angeles and Anchorage go forward on the second Sunday in March and back on the first Sunday in November. Where the two sides change on different weekends, there is a stretch of days when the difference is what neither party expects.

Frequently asked questions

What is the time difference between Australia and the United States?

There is no single figure. the United States spans 6 of the offsets in this data, so the difference runs from 12 hours (Perth to New York) to 20 hours (Brisbane to Honolulu). Any converter giving one number for this pair has quietly picked a city.

How many hours ahead is the United States of Australia?

It depends which part of the United States you mean. The table on this page gives every combination; the extremes are 12 hours and 20 hours.

Does the difference between Australia and the United States change during the year?

Yes. 22 of the 24 city combinations here shift by an hour at some point, because the two sides change their clocks on different weekends or one of them does not change at all.

About these places

Brisbane. Brisbane is UTC+10 and does not change its clocks, while Sydney and Melbourne — the same offset in winter — go an hour ahead in October. For half the year Queensland is an hour behind its southern neighbours, which is a standing annoyance for anyone scheduling across the east coast.

Sydney. Sydney is UTC+10 in winter and UTC+11 from October to April. Its summer is the northern hemisphere's winter, so the gap to Europe and North America swings by two hours over the year rather than staying put.

Melbourne. Melbourne keeps the same clock as Sydney, UTC+10 in winter and UTC+11 in summer, and changes on the same dates. The pair are the reason "Australian Eastern Time" needs the Standard or Daylight qualifier to mean anything between October and April.

Perth. Perth is UTC+8, the same as Singapore and Beijing, and is the only Australian capital that does not change its clocks. Western Australia has rejected daylight saving in four referendums, most recently in 2009.

New York. New York is UTC−5 in winter and UTC−4 from March to November, and it changes clocks on different weekends from Europe — a fortnight in March and a week in autumn when the transatlantic gap is an hour off what everyone expects.

Chicago. Chicago is UTC−6 in winter, the US Central zone, and the one people most often mean by an unqualified "CST" — a reading that collides with China Standard Time fourteen hours the other way.

Denver. Denver is UTC−7 in winter, the US Mountain zone, and the smallest of the four continental US zones by population. Arizona, in the same zone, does not change its clocks, so for half the year Denver and Phoenix are an hour apart.

Los Angeles. Los Angeles is UTC−8 in winter and UTC−7 from March to November. California voted in 2018 to move to permanent daylight saving and has not been able to: the change needs an act of Congress, which has not come.

Anchorage. Alaska is UTC−9 in winter, one hour behind the US Pacific coast, and covers a longitude range that would justify four zones. The state consolidated into one in 1983 so that Anchorage business hours would overlap with the rest of the country.

Honolulu. Hawaii is UTC−10 and does not change its clocks, so it drifts an hour further from the mainland every March. It is the furthest behind of any populated US zone, and the overlap with a European working day is essentially nil.

The same pair from the other end

This page reads the difference as the United States against Australia. The United States to Australia states the same gap the other way round, which is the one to send someone if they are the one doing the travelling.

Other country pairs

Every Australia pair · Every the United States pair · All country pairs · City pairs