🌸 Spring Forward
3:00 AM → 4:00 AM · lose an hour
🍂 Fall Back
4:00 AM → 3:00 AM · gain an hour
Greece keeps EET in winter and shifts one hour forward for the summer.
Countdown to the next change
Spring transition
Lose an hour of sleep, gain an hour of evening daylight
Autumn transition
Gain an hour of sleep as standard time returns
Longer evenings
Sunset falls an hour later through the summer months
Earlier sunrises
Winter mornings get light sooner once the clocks go back
Does DST Actually Save Energy?
This was the original justification, and it is the claim that has held up worst. A US Department of Energy report to Congress in 2008 measured the four weeks added to DST in 2007 and found a saving of about 0.5% of daily national electricity use — real, but small.
Other work has found no saving at all. A well-known study of Indiana, which adopted DST statewide in 2006, found residential electricity use actually rose by 1–4%: households used less lighting but more air conditioning on hot summer evenings. Any lighting savings are also partly offset by extra petrol use as people travel more in the lighter evenings.
Technology and Time Changes in 2025
Phones, computers and anything else that syncs with an internet time server handle the transition on their own. What still catches people out in Greece is the long tail of devices that don't: car dashboards, ovens and microwaves, wall clocks, older thermostats, and cheap alarm clocks with a DST setting hard-coded to a schedule that has since changed.
For anyone running servers, the transitions are a recurring source of bugs — duplicated or missing local timestamps around the changeover, cron jobs that fire twice or not at all, and stale operating system timezone databases. Storing timestamps in UTC and keeping the tzdata package current avoids almost all of it.
Did you know?
- Arizona and Hawaii are the only US states that skip DST statewide, along with the territories of Puerto Rico, Guam, American Samoa and the US Virgin Islands.
- Germany and Austria-Hungary were the first countries to adopt DST nationally, in April 1916, as a wartime fuel-saving measure.
- The Uniform Time Act of 1966 ended a chaotic period in which US cities set their own clock-change dates, and established a uniform national schedule.
Frequently asked questions
When do the clocks change in Greece in 2025?
Clocks go forward on Sunday, March 30, 2025 and back on Sunday, October 26, 2025.
Which way do the clocks go?
"Spring forward, fall back" is the usual mnemonic: forward one hour in spring, back one hour in autumn.
Do I have to change anything myself?
Phones, computers and anything that syncs over the internet update on their own. Car clocks, ovens, microwaves and older wall clocks generally do not.
Is Daylight Saving Time being scrapped?
It has been proposed in many places and adopted in few. The European Parliament voted in 2019 to end mandatory clock changes and the change has stalled; in the United States the Sunshine Protection Act has repeatedly passed the Senate without becoming law. Most of the world that changes its clocks is still changing them.