Australian Eastern (AEST/AEDT)
Sydney operates on Australian Eastern (AEST/AEDT). This time zone does not observe Daylight Saving Time.
Time Zone: Australian Eastern Standard/Daylight Time — Standard Offset: UTC+10 (AEST) — DST Offset: UTC+11 (AEDT)
Country: Australia
This city observes Daylight Saving Time, so the UTC offset changes twice per year. Always verify the current offset when scheduling across time zones.
Sydney's Daylight Saving Time runs opposite to the Northern Hemisphere — clocks spring forward on the first Sunday in October and fall back on the first Sunday in April. This means the time difference between Sydney and cities like London or New York fluctuates throughout the year. During the northern winter (when both Sydney's DST and New York's standard time are in effect), Sydney is 16 hours ahead of New York. During northern summer, the gap shrinks to 14 hours.
The Australian Securities Exchange (ASX) opens at 10:00 AM AEST and closes at 4:00 PM AEST. Sydney's time zone creates excellent overlap with Asian markets — when the ASX opens, Tokyo is still trading (1 hour behind), and Hong Kong and Singapore are 2-3 hours behind. This makes Sydney a key player in the Asia-Pacific financial corridor. Sydney's proximity in time to major Asian economies has fueled Australia's strong trade relationships with China, Japan, and South Korea.
Coordinating between Sydney and the US is notoriously challenging due to the 14-16 hour gap. The most practical approach: early morning Sydney calls (7-8 AM AEST) catch the US East Coast at 4-5 PM the previous day. For UK coordination, Sydney is 10-11 hours ahead — a 9 AM Sydney meeting is 10 PM London the night before, which is tough. The realistic overlap is narrow: 7-8 AM Sydney = 8-9 PM London (previous day).
Australia spans three major time zones (Western, Central, and Eastern) plus several territories with unique offsets. South Australia and the Northern Territory use UTC+9:30 — a half-hour offset that complicates scheduling further. Not all Australian states observe DST — Queensland, Western Australia, and the Northern Territory skip it, meaning the domestic time map changes seasonally. Sydney, Melbourne, and Canberra all share AEST/AEDT.