Residents in Victoria, New South Wales, Tasmania, South Australia and the Australian Capitol Territory will lose an hour's sleep on Sunday, as clocks reset at 2am.
Smartphones should automatically reset to the correct time, while clocks should be wound forward one hour.
Clocks were first wound forward in 1942 to save on fuel during the First World War. The cost saving measure was then abandoned in 1944, until is was adopted once again in Tasmania in 1967. NSW, Victoria, Queensland, South Australia and the ACT followed suit in 1971, although Queenslanders discontinued the practice the following year.
The state government is urging Victorians to change their smoke alarm batteries every time they adjust their clocks.
Daylight savings will end on Sunday, April 2.
