Permanent Daylight Saving Time vs. Standard Time: How It Would Affect Sunrise and Sunset in Your City

Twice a year most of the United States changes its clocks, and twice a year the same question comes back: why not stop? The trouble is that "stop changing the clocks" can mean two very different things. We could keep daylight saving time all year, the summer clock, or keep standard time all year, the winter clock. The Sun does not care which one we pick, but your mornings and evenings do.

In short: daylight saving time all year would make sunrise and sunset an hour later in winter, and standard time all year would make them an hour earlier in summer. Because we calculate sunrise and sunset for every place on this site, we can show exactly what that means where you live. Type a town or city to see its whole year under the three clocks: the solid lines are today's clocks, with their spring and autumn jumps; the dashed lines are the two permanent options.

See it for your location

Today’s clocksStandard time all yearDaylight time all year

	Today’s clocks	Standard all year	Daylight all year

The Two Options

Daylight saving time all year means keeping the summer clock through the winter. Winter evenings get an hour more light after work and school, and winter mornings get an hour darker. In the north and west of a time zone, sunrise would come close to 9 am in late December.

Standard time all year means keeping the winter clock through the summer. Summer mornings get an hour lighter, often with sunrise before 5 am, and summer evenings lose an hour: a late-June sunset at 9 pm becomes a sunset at 8 pm.

Neither option gives us more daylight. The day is just as long either way; what changes is the time on the clock when the Sun rises and sets. Daylight saving time all year moves an hour of light from winter mornings to winter evenings. Standard time all year moves an hour of light from summer evenings to summer mornings.

What It Would Mean in US Cities

Each option has a cost and a benefit, and they fall in the same season. These are the extremes of 2026 in eight cities, with the date of each, under today's clocks and under the permanent clock.

Daylight Saving Time All Year: the Winter

The cost is in the morning. The latest winter sunrises would come in Detroit and Indianapolis, which sit on the western side of Eastern Time: after 9 am in early January. The benefit is in the evening: the earliest sunset of the year, around 4:15 pm in Boston, Seattle and Chicago, would move to around 5:15 pm.

The jump in the latest sunrise is not always a full hour, because today the latest sunrise of the year often does not happen in winter. In most of these cities it comes on the last day of daylight saving time, at the end of October, or on the day the clocks spring forward in March, when sunrise suddenly comes an hour later.

Standard Time All Year: the Summer

Here the benefit is in the morning and the cost is in the evening. Boston, Seattle and Chicago would see the summer Sun rise soon after 4 am, and the latest sunset of the year would come an hour earlier everywhere: around 8:15 pm in Seattle and Detroit instead of after 9 pm.

Has Anyone Tried It?

The United States has, twice. During the Second World War the whole country stayed on daylight saving time from 1942 to 1945, which was called "War Time". In January 1974, in the middle of an energy crisis, the country switched to daylight saving time all year again. It was popular when it was announced and much less popular once children were walking to school in the dark, and standard time came back that autumn.

Federal law today lets a state stay on standard time all year, which is what Hawaii and most of Arizona do, but it does not let a state stay on daylight saving time all year. Around twenty states have passed laws to switch to permanent daylight saving time if Congress ever allows it, and the federal Sunshine Protection Act, which would do that for the whole country, passed the Senate in 2022 but did not become law.

Elsewhere, Mexico stopped changing its clocks in 2022 and stayed on standard time, except for the towns along the US border, which still change with the United States. Paraguay chose to stay on its summer clock from 2024. In the European Union, the European Parliament voted in 2019 to end the seasonal changes, but the member states have never agreed on a common position, and the EU still changes its clocks twice a year.

So Which One Is Better?

There are two questions here. For health, the American Academy of Sleep Medicine recommends standard time all year, because it keeps the clock closer to the Sun and gives light in the morning, when the body clock needs it. For everyday life, supporters of daylight saving time all year point to the extra hour of evening light in winter, for outdoor activity and shopping after work.

What the numbers make clear is that there is no option without a cost: someone, somewhere, gets either very dark winter mornings or very early summer sunrises. The simulator above shows which one it would be where you live.

And you, what would you prefer?

Daylight saving time all year Standard time all year Keep changing the clocks twice a year

Times calculated with the NOAA solar position algorithm, as everywhere on this site (see how we calculate).