Daylight saving: When it starts, why we have it and how to change the time on your phone

Explainer: Get ready to spring into summer; daylight saving begins this month which will mean we lose an hour of sleep on Sunday - but the days should be warmer and brighter.

So when do the clocks switch over? Why do we observe daylight saving? And how do you check the time on your phone is accurate? Here's everything you need to know.

Do the clocks go forward or back?

Spring into summer! Clocks will go forward one hour at 2am on Sunday 28 September.

That means you'll lose an hour's sleep and it will be darker when you wake up in the morning.

It also means the sun will set an hour later, allowing extra time in the evening for those summer BBQs or some sport/ exercise.

How do I change the time on my phone?

You probably won't need to, because most smart phones will adjust to time zones automatically. Here's how to check if your smartphone does that:

Android: Go into the clock app, tap more and then go into settings. Then go into change date and time, select set time zone automatically and then select use location to set time zone.

iPhone: Open settings, select general, to go date & time and make sure set automatically is turned on

Samsung: Open settings, go to general management, select date and time and then make sure automatic date and time is turned on. This should mean your phone will automatically reflect the time depending on where you are.

Why do we have daylight saving?

Because the Earth is on a tilt (of about 23 degrees, for those curious), we are exposed to more sun during summer and less during winter.

That means the days are longer during the warmer months and shorter in the colder months.

Daylight saving is intended to make the most of those long daylight hours. It means an extra hour of light on summer evenings, rather than super early in the mornings when hardly anyone is awake to enjoy it.

How long have we been doing this?

New Zealand first observed daylight saving in 1927.

However, the dates that clocks went forward and back, and the amount of time they were changed, varied over the following years.

In 1941, daylight saving was extended year-round under emergency regulations to help save energy during World War II.

Five years later, daylight saving time (or summer time as it was then known) was adopted as standard time, effectively discontinuing daylight saving.

In 1975, daylight saving was introduced again.

It was extended to its current dates - from the last Sunday in September to the first Sunday in April - in 2007.

When will daylight saving time end?

Daylight saving time ends every year at 3am on the first Sunday in April.

That means it ends in 2026 at 3am on Sunday 5 April.

Do other countries observe daylight saving?

They do, but they're in the minority. About two thirds of the world's countries do not change their clocks throughout the year, according to Pew Research.

US President Donald Trump has pushed for an end to daylight saving, calling it inconvenient and costly.

In the last decade alone, Azerbaijan, Iran, Jordan, Namibia, Russia, Samoa, Syria, Turkey and Uruguay have all ended their seasonal time changes.

According to the Pew Research, in the US, Hawaii and most of Arizona, as well as some territories, do not observe daylight saving time. Australia, Brazil and Canada are similar. For example, in Australia, daylight saving is not observed in Queensland, the Northern Territory, Western Australia, Christmas Island or the Cocos (Keeling) Islands.

The practice is most popular in Europe, where 37 out of 44 countries observe daylight saving, and it's also observed in parts of North America, Latin America and Australia.

Egypt is the only African nation with daylight saving after bringing it back in 2023.

Countries close to the equator do not usually change their clocks as the length of their days does not vary enough throughout the year to justify it.

How long does it take for the body to adjust?

The spring transition is the easier one - going into daylight saving time, putting the clock forward an hour "we just squash an hour out of our day", says Dr Karyn O'Keefe, from the Sleep/Wake Research Centre.

It's not such a problem on Sunday, but on Monday morning we might feel robbed of that extra hour when getting up to start the working week.

"So we can be frustrated in the evening or at night and tired and groggy in the morning and have short sleep as well. It's like this combination of feeling really groggy and grotty for a couple of days at least."

What if I'm working when the time changes?

The rules around getting paid for working during daylight saving time are set out in the Time Act 1974.

It says that if you're working when clocks go back an hour, you are entitled to be paid for that extra hour.

For example, if your shift started at 10pm and finishes at 6am, you will have actually worked nine hours and must be paid for nine hours of work.

If you're working on 28 September when the clocks go forward, you are still entitled to be paid for your normal hours. In this instance, a 10pm-6am shift will only mean seven hours of work, but you must be paid for eight.

I've changed the clock on my microwave - what next?

Daylight saving is a good time to check the batteries on your smoke alarm by pushing the test button to sound the alarm.

Check the alarm's expiry date too - most last a maximum of 10 years - and give the cover a clean to avoid false alarms from dust buildup.

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