Why Do We Have Daylight Saving Time?

(Last Updated On: June 14, 2021)

If you’re a fan of feeling like you have extra time, the whole idea of daylight saving time is probably both the best and worst thing for you. Once per year you get to feel like you’ve gained an entire hour–but it comes with the knowledge that you will soon have to feel the pain of effectively losing an hour in the following seasons. We know for starters DST is getting substantially less popular, and it’s really weird in how it’s even observed. So, why do we even have daylight saving time?

Also, it’s seriously wack. Let’s take Arizona as our example. They don’t observe daylight saving time. But the Navajo Nation, whose borders are within Arizona, do. However, the Hopi Reservation, within the borders of the Navajo Nation, do observe daylight saving time. But a small part of the Hopi reservation is a part of the Navajo Nation–so that little corner does observe daylight saving time. 


Further Reading: Why Doesn’t Arizona Observe Daylight Saving Time?

Daylight Saving Logic

Let’s logic out daylight saving time for a hot second. Which means we have to go back in time–to a time where clocks were less of a thing and we tracked time by daylight. In such a time, the way society functions and gets work done is largely based on how much light remains in the day. 

As seasons change, so does how much light we have on any given day. More limited daylight means society has to optimize its use more. So kicking clocks back by an hour when there’s less daylight basically means people will get their stuff done faster–effectively leaving people more daylight after they finish all their daily tasks.

Which doesn’t work all that well when you realize that people will have less daylight at the start of their day.


So yeah, the origins of daylight saving time have to do with pre-industrial society. Mostly because if you’re working in a factory or office, the Sun has little to no bearing on whether or not you’re able to do your job.

But way back before standardized clocks, societies had their ways around scheduling that didn’t involve kicking back hours. Time was pretty flexible, and everything was just related to whether or not the Sun was active. Roman clocks didn’t have standardized hours–they just said “every day is 12 hours of sunlight let’s just divide it up.” Which means hours were longer in the summer and shorter in the winter during the day, and the other way around at night.

That kind of timekeeping works quite well when you’re localized to a single geographic region, and don’t have to interact/trade with people from other regions. You know, because seasons are different in different parts of the world–depending on how far away from the equator you are. Suffice to say, the system of uneven hours was people had independently developed for their communities was going to have to go at some point

Thus, once clocks and hours became standardized within communities (for some this was the 14th century), some idea of daylight saving time as we know it would have to be implemented.

Getting Started

Many credit Benjamin Franklin with being the big brain behind daylight saving time. In no small part because he wrote “early to bed and early to rise makes a man healthy, wealthy, and wise” that one time in 1785. However western daylight saving time wasn’t observed until around WWI as a way to maximize daytime hours and minimize fuel consumption for keeping things lit when it was dark out.

The American version of DST (going back in November and forward in March) got started in 2007. It used to be April to the very end of October, but Bush extended it by roughly a month. 

Other Nations?

You may be wondering why most of the countries observing daylight saving time are western. That’s because the vast majority of them are. People near the equator have no need for any kind of daylight saving time–since sunlight near the equator is relatively constant year round. So happens many western countries are far enough up north to have used daylight saving time in the past. It’s a good rule of thumb that the farther a given nation is away from the equator, the more likely it is to observe the clock shifting. 

Is This Obsolete?

The quick, logical answer is yes–for quite a few people anyway. Many industrialized nations don’t do the whole outdoor-labor thing, instead sticking to schedules based on their watches more than the Sun itself. Thus, it’s not really necessary to preserve daylight beyond personal preference for people who don’t work outside.

For those who also have to plan international meetings, things get pretty logistically nuts as well. Because of the people that do observe daylight saving time, none of them really agree on when it starts and ends. Take New York and London–where New York starts observing DST roughly two weeks before London does. Which means in a 3 week time span, people in New York go from being 5 hours apart, to 4, to 5 again.

Let’s now throw in Sydney, which leaves daylight saving time a week after London enters it. In that same timespan, Sydney is 11, 10, and 9 hours apart from London, and 16, 15, and 14 hours from New York. Nuts? Repeat it again in 6 months. 

Daylight Saving Time and Energy 

Some argue that DST may save energy–which perhaps is valid. You could, however, argue that it uses more energy as well. If people are awake more in the daylight hours, they’re going to be spending more time cranking the air conditioning up–especially in hotter places. That’s probably quite a bit more expensive than a lightbulb.

Regardless of which side of that debate you fall on, it’s not swinging things much in either direction. Like less than 1% in either direction. Like 0.03%. Basically, it doesn’t matter.

That’s not to say this all isn’t costly–the resulting sleep deprivation actually does cause an increase in heart attacks and suicides. People also don’t work as well following their clock shifting–costing over $400 million in lost productivity from American workers in 2014. It’s probably not great to measure something’s worth based on how “productive” it is for American industry, but there’s a salient point there. Daylight saving time makes things hard for people who don’t rely on the Sun for time.

Further Reading: Daylight Saving Time Facts and Myths

See if you know who does and doesn’t observe DST here.



About Kyler 727 Articles
Kyler is a content writer at Sporcle living in Seattle, and is currently studying at the University of Washington School of Law. He's been writing for Sporcle since 2019; sometimes the blog is an excellent platform to answer random personal questions he has about the world. Most of his free time is spent drinking black coffee like water.