Technical Specifications & Standards
Official chronometric properties, ISO standards, and international database registry identifiers for Australian Eastern Daylight Time:
Daylight Saving Time (DST) Transitions
⬆️ Spring Forward (Clocks Advance)
First Sunday in October at 02:00 AM (Clocks advance to AEDT)
⬇️ Fall Back (Clocks Return)
First Sunday in April at 03:00 AM (Clocks return to AEST)
Observing Jurisdictions & Subdivisions
1 Sovereign NationsSovereign nations, administrative subdivisions, and regional territories officially operating under AEDT:
Regional Subdivisions & Territory Details
Financial Markets & Trading Hours
Australian markets open Monday morning while it is still Sunday afternoon (5:00 PM EST / 2:00 PM PST) in the United States, giving early direction to currency futures.
Local Hours: 10:00 - 16:00 AEDT
UTC Window: 22:00 - 05:00 UTC
Major Cities in AEDT
Primary metropolitan centers and financial hubs observing this time zone:
Adoption History & Astronomical Facts
Year Established: 1971
Modern annual daylight saving was established across New South Wales, Victoria, Tasmania, and the ACT following trial legislation passed during the 1970–1971 summer to allow more evening outdoor recreation.
Because seasons are reversed in the Southern Hemisphere, Sydney advances its clocks into AEDT in October just as New York and London are preparing to fall back to standard winter hours.
Frequently Asked Questions about AEDT
What does AEDT stand for?
AEDT stands for Australian Eastern Daylight Time, eleven hours ahead of Coordinated Universal Time (UTC+11).
When does AEDT start and end?
AEDT begins on the first Sunday in October and ends on the first Sunday in April.
What is the difference between AEDT and AEST?
AEDT is summer daylight saving time (UTC+11), while AEST is winter standard time (UTC+10).