Getting back to a sleep schedule:
how to move your clock back after a holiday

You haven't lost sleep:
your clock has moved

There are two different things that feel the same on a Monday morning, and if you confuse them, you treat the wrong problem.

The first is sleep debt: you slept less than you needed and your body wants the hours back. The second is a phase shift: you slept enough, but at different times, and now you're asking a body that got used to falling asleep at 1:30 am to fall asleep at 11:00 pm. Your body isn't refusing out of stubbornness. It's simply that, at 11:00 pm, it's still late afternoon as far as it's concerned.

The test is simple. Think back to how you slept in the last week of your holiday. If you slept eight hours, but from two until ten, you don't have a deficit, you have a time shift. If you slept both too little and too late, you have both, and the plan below only fixes one of them. The other is paid off with full nights, not with tricks, and if you feel you're sleeping enough and still feel shattered, we've written separately about why you're tired even when you sleep 8 hours.

Your clock doesn't run on 24 hours:
it runs on 24 and a quarter

In 1999, a group from Harvard published in Science the results of a protocol that completely removed light and time cues from participants' lives, to see how long an internal day really lasts. The answer: the intrinsic period of the human circadian clock averages 24.18 hours. The same value in young and older people, contrary to the older idea that the clock shortens with age.

24.18 hours means 24 hours and about 11 minutes. In other words, your clock, left to its own devices, runs a little late every day. It never runs fast. That's why on holiday you gradually end up going to bed later and later, without ever deciding to, and never the other way round.

In real life the delays don't add up in a perfectly straight line, because daylight partly resets you anyway, even on holiday. But the direction is always the same, and once the morning alarm and the fixed schedule disappear, nothing pulls the clock back. That's why coming back takes effort, while drifting away took none.

Social jet lag:
the technical name for that Monday morning feeling

Chronobiologists have a measure for the difference between when you sleep when you can and when you sleep when you have to. It's called social jet lag, and the formula is simpler than it sounds: the difference, in absolute value, between the midpoint of your sleep on free days and the midpoint of your sleep on work days.

The midpoint is exactly what it sounds like: if you sleep from 11:00 pm to 7:00 am, the midpoint is at 3:00 am. If on holiday you slept from 1:30 am to 9:30 am, the midpoint was at 5:30 am. The difference, two and a half hours, is your social jet lag. The measure comes from the work of Till Roenneberg and colleagues, built on the Munich ChronoType Questionnaire, a database that had reached more than 185,000 participants by July 2017.

The number is useful because it tells you how far you have to move, not how tired you are. Twenty minutes doesn't need a plan. Two and a half hours does. If you want the bigger picture, including the extra pressure that comes in September, you'll find it in our guide to sleep and stress.

Morning light is the main lever:
and it needs time, not good intentions

Light that reaches your eyes early in the morning pulls the clock earlier. Evening light pushes it later. That's the whole mechanism, and the rest of the sleep advice is, at best, arrangements around it.

The part hardly anyone mentions is how much light this takes. A study published in 2020 in Frontiers in Neuroscience took 37 adolescents with late bedtimes and gave them bright light on two weekend mornings, then measured their clock by the time melatonin secretion began in their saliva.

The groups had between 11 and 13 participants each, and the participants were adolescents aged between 14.7 and 18. It doesn't translate one to one to a 35-year-old woman. The direction, however, is the useful lesson: an hour and a half of light didn't beat the group that got nothing, while two and a half hours moved the clock by a whole hour in two mornings.

The practical conclusion for you: it isn't about looking out of the window for five minutes with your coffee in hand. It's about going outside and staying there. Outdoor light, even under a completely overcast sky, is far brighter than what you have in the kitchen with all the lights on, and a closed window cuts out a good part of it.

The five-morning plan:
what you actually do and in what order

The first rule of the plan is counterintuitive: don't touch your bedtime. Sleep doesn't come on command, and if you get into bed two hours earlier, you'll spend two hours staring at the ceiling and end up dreading your own bedroom. What you adjust is your wake-up time, the only one you can set directly, and your morning light. Bedtime follows on its own after them, within two or three days.

If your gap is under an hour, move your wake-up time all at once and go straight to day three. If it's two hours or more, move it in steps of 20 to 30 minutes a day.

If you're already back at work and don't have five free days, the plan still works: skip the gradual steps, set the wake-up time you need straight away and keep up the morning light. There will be two hard mornings. The third is noticeably easier. If on these evenings you're also looking for some evening support, it's worth reading first about the difference between magnesium glycinate, citrate and oxide, because they aren't interchangeable.

What ruins the plan:
afternoon naps, alcohol and Saturday

You don't need a list of thirty sleep hygiene rules. You need to avoid wrecking, within five days, the one thing you're building: a fixed wake-up time followed by light.

The screen part is the hardest to stick to, and if you want a structure for it, we have one in the seven-day digital detox plan. The weekend, though, is where most people give in, and that's understandable. One extra hour on Saturday doesn't ruin anything. Three extra hours mean that on Monday you start all over again, with the same feeling and the same bewilderment, plus the brain fog that comes with it.

With children it's a different story:
and they're usually the only ones who get reset

In the last week of August, the same thing always happens in homes with children. The children's schedule is carefully shifted, days in advance, with gradual wake-ups and dinner at school-term times. The schedule of the adult organising it all stays exactly where the holiday left it, and on the first day of school it's the parent who wakes up feeling as if they've been hit by a car.

The levers are the same for everyone: a fixed wake-up time and outdoor light in the morning, started a few days in advance. The difference is that with children no supplement comes into the question, and in teenagers the clock is naturally pushed later anyway, which makes a September morning a negotiation, not an order.

What melatonin can do:
exactly that and nothing more

In the European Union, melatonin has a single authorised health claim that a supplement can use: it contributes to the reduction of time taken to fall asleep. The condition of use is just as precise: at least 1 mg, taken close to bedtime.

It's worth reading what it doesn't say. It says nothing about staying asleep. It says nothing about sleep quality. It says nothing about how you feel the next day. And it says absolutely nothing about moving your internal clock, which is actually your problem after a holiday.

That makes melatonin a side helper in your reset week, not its engine. It shortens the wait on the evenings when you go to bed earlier than your body is used to. It doesn't replace the mornings outside. We've detailed doses, timings and side effects in our complete guide to melatonin.

What's in our
melatonin gummy

Melatonin 5mg is a blackberry-flavoured gummy. One serving is two gummies and contains 5 mg of melatonin derived from pistachio, 200 mg of 25:1 chamomile extract and 200 mg of 10:1 lavender extract. Made in Romania.

Melatonin contributes to the reduction of time taken to fall asleep, and the beneficial effect is obtained with 1 mg, taken close to bedtime. The chamomile and lavender are there for the taste and for their long history of use in evening tea.

The part you don't often see written on a product page: 5 mg is five times the threshold at which the effect is obtained. More doesn't automatically mean better. If it's your first time taking melatonin, a single gummy, which is 2.5 mg, is still above the threshold and is a better start.

And one thing to remember: it isn't a sleeping pill, and it doesn't replace a conversation with your doctor if you haven't been sleeping for months.

When it isn't about the holiday:
signs that the question belongs with someone else

Holiday jet lag is fixed in a few days of fixed times and light. If it doesn't get fixed, it wasn't holiday jet lag.

It's worth talking to a doctor if three weeks of a stable schedule have passed and you still can't fall asleep, if you wake up night after night at the same time and stay awake for hours, if someone has told you that you snore with pauses in your breathing, if you nod off at the wheel or in meetings, or if your tiredness no longer has anything to do with how much you've slept. An article can't make a diagnosis and shouldn't try.

Frequently asked questions:
about getting back on schedule after a holiday