How to adjust your sleep to daylight saving time

When the clocks change, go by the new clock and get up when you always do, starting the first morning. Your body can take a week or so to catch up, sometimes longer in spring.

When do the clocks change in 2027?

In most of the US and Canada the clocks go forward an hour at 2am on Sunday, March 14, 2027. Hawaii and most of Arizona keep the same time all year. The UK goes forward at 1am on Sunday, March 28, and Ireland and most of Europe change that day too.

The clocks go back on October 31, 2027 in the UK and Europe, and on November 7 in the US and Canada. Parts of the southern hemisphere change on the opposite schedule. New South Wales, in Australia, puts its clocks back an hour on April 4.

In July 2026 the US House voted 308 to 117 to make daylight saving time permanent. The Senate sent the bill to its commerce committee the next day and, as of early November 2026, hasn't voted on it. Until it passes the Senate and the President signs it, the clocks keep changing twice a year.

Sleep doctors also want the clocks to stop changing, though they'd keep standard time, the clock we use in winter, all year. A 2024 American Academy of Sleep Medicine position statement says standard time fits the body clock best.

Why is the spring change harder?

Springing forward takes an hour out of one night, and for the next few days your body lags an hour behind. Bedtime comes before you're sleepy, and a 7am alarm goes off at what still feels like 6.

A study of 732,835 fatal crashes in the US, from 1996 to 2017, found the risk rose about 6% in the week after the spring change, and the rise was biggest in the morning. The fall change made no difference to the overall risk.

How long does it take to adjust to the time change?

Adjusting to the spring change can take a week or more, though the research is mixed. A 2013 review, drawing mostly on small studies, found sleep came more slowly and was more broken for at least the week after. A 2025 review of 27 studies also found shorter, poorer sleep and more daytime sleepiness, more so in night owls. Its authors point out how much the studies varied.

The clearest loss is the first night. Among 11,780 UK adults aged 43 to 78 who wore activity trackers, sleep on the Sunday the clocks went forward was about an hour shorter than on the Sunday before. Weekday sleep after that didn't drop.

What helps in spring

Don't sleep in on the Sunday the clocks go forward, however much you want that hour back. Get outside once it's light, as early in the morning as you can. Morning light pulls your body clock earlier, and there's far more of it outdoors than in. Keep the last hour or two before bed dim that week, since bright light late in the evening pushes your body clock later.

Early wakers get a break in spring, since 5am becomes 6am on the new time. We'd go easy on bright light first thing so you don't undo it, and get your daylight in the late afternoon instead. We're going on how light moves the body clock here, and nobody has tested it around the clock change.

Wait until you're sleepy to go to bed, even if that's a little later than usual for a few nights. Waiting it out in bed while wide awake tends to make things worse. Once you're more annoyed than sleepy, get up and sit in a dim room until you're drowsy, then try bed again. You're better off sitting up in bed with a small light on if you've taken something for sleep or your balance is shaky at night. If you take something for sleep, take it only as prescribed and talk to your doctor before changing it.

We'd ease in during the week before if the change usually hits you hard. Starting that Wednesday, get up 15 minutes earlier each morning, so by Saturday you're up an hour early. Move bedtime earlier only as you start to feel sleepy earlier.

If you're drowsy, don't drive. That first week, watch for it in the mornings most of all, and pull over somewhere safe if sleepiness creeps up at the wheel.

What happens when the clocks go back?

Your body runs an hour ahead for a few days after the clocks go back in the fall. You'll get sleepy before bedtime and may be awake before the alarm.

Do you get an extra hour of sleep?

Some of the extra hour you get when the clocks go back does turn into sleep. The UK tracker study of 11,780 adults found people slept about half an hour longer on the Sunday the clocks went back than on the Sunday before, and their weekday sleep barely changed.

The fall change can still unsettle sleep for a week or so. In a Canadian survey of adults aged 45 to 85, the 573 asked in the week after the clocks went back reported more trouble falling asleep than the 588 asked the week before (7.1% against 3.3%), and more trouble staying asleep (12.9% against 8.2%). By two weeks after the change the gap was gone. The survey compared different people, so it can't show the clocks caused it.

Anyone who already wakes too early may notice it most, with 6:30 turning into 5:30 for the first few days.

What helps in the fall

After the clocks go back, your get-up time stays put. If you normally get up at 7, get up at 7 on the new clock, even after waking at 6. You're awake at 6 because your body is still on the old time. It catches up if you stick with your get-up time.

On those early mornings, leave the lights low until 7 and rest as best you can. Bright light that early keeps your body clock running ahead. When you can't settle, turn on a small lamp in another room and sit there until you're drowsy again. With something for sleep in your system, or shaky balance in the dark, skip the walk and sit up where you are, with a bedside lamp on low.

Try to stay up until close to your usual bedtime, too. Nodding off on the couch at nine makes it harder to fall asleep later.

Easing in works here too, the other way. For the four days before, set your alarm 15 minutes later each morning and let bedtime drift later with it. Skip this one if you already wake early, since a later alarm only means more time lying awake.

Talking to a doctor

Poor sleep on three or more nights a week for three months, whatever set it off, is reason enough to see a doctor. Ask them about CBT-I too. For chronic insomnia, the American College of Physicians recommends trying it first. Don't wait that long if you snore loudly, wake up gasping, nod off during the day, or wake very early most days feeling low.

A short night can bring on a manic episode in bipolar disorder or a seizure in epilepsy. With either, talk to your doctor before the clocks change, in spring or fall, about keeping your sleep steady that week.

How Goodmorrow handles the change

At 6pm the evening before the clocks change, we send you a message with your get-up time in it, something like "The clocks go forward an hour tonight. Tomorrow, get up at 7:30 on the new time." We skip that day's lesson. The next morning opens with "First morning on the new clock," and the reply to your morning note knows which way the clocks moved.