How to Get More Deep Sleep

If you have started paying attention to your deep sleep, there is usually a reason. Either you are waking up tired despite a decent stretch in bed, or a tracker has told you your deep sleep is low, and you are not sure what to do with that. Both are worth taking seriously. The honest answer is that deep sleep is harder to control directly than most advice suggests, and easier to protect than you might think.

Deep sleep is stage N3, the deepest part of the non-REM portion of your sleep cycle. It is also called slow-wave sleep, after the large slow brain waves that show up on an EEG (electroencephalogram). It accounts for roughly a quarter of a night’s sleep in a healthy adult, and it is the stretch during which the body repairs tissue, builds bone and muscle and supports immune function.

It is also the hardest stage to wake someone from. Some people will sleep through noises above 100 decibels while in N3, and anyone woken out of it gets 30 minutes to an hour of the mental fog known as sleep inertia.

For the full picture on what it does and how much you should be getting, read our guide to how much deep sleep you need. This article is about the practical side.

Partly. This is where most advice on this topic quietly oversells itself, so it is worth being clear about what is going on.

Deep sleep is largely self-regulating. Your body decides how much it needs based on how long you have been awake and how much deep sleep you have recently had, then front-loads it into the early cycles of the night. Deep sleep dominates the first half of the night and tapers off towards morning, while REM does the opposite. You do not get a say in that scheduling.

What that means in practice is that you cannot simply decide to have more deep sleep tonight. A review of slow-wave sleep from the cell to the clinic works through the various techniques researchers have tried to enhance it directly, and most of them are laboratory methods rather than anything you can do at home.

The useful framing is different. You are not trying to manufacture deep sleep. You are trying to give your body a long enough, calm enough window to take what it needs, and removing the things that cut it short. That is genuinely achievable, and it is what the rest of this article covers.

It’s not always easy to get enough deep sleep, but to help you get more, we have 7 tips for you:

A consistent schedule keeps your circadian rhythm aligned, which matters because the timing of your sleep affects its structure. Going to bed at wildly different times shifts your sleep relative to your body clock, and the deep sleep you would have got early in the night can end up landing somewhere less useful. Holding roughly the same wake time at weekends is the part most people skip and the part that helps most. If your schedule has drifted, our guide on resetting your body clock covers the practicalities.

Exercise is one of the better-supported ways to improve sleep quality generally. The standard advice to avoid evening exercise altogether turns out to be too blunt.

A 2025 study in Nature Communications tracked 14,689 physically active people across more than 4 million nights of biometric data. Later and harder evening exercise was associated with delayed sleep onset, shorter sleep and lower sleep quality. The useful finding is the threshold. Exercise finishing 4 or more hours before sleep showed no association with disruption, regardless of intensity. It was observational data from wearables rather than a controlled trial, so treat it as a strong signal rather than proof.

So the workable rule is to train whenever suits you, and keep the genuinely strenuous sessions to more than 4 hours before bed. A gentle evening walk is not the problem.

A cool, dark, quiet room supports the whole night rather than deep sleep specifically, which is still worth having. Cleveland Clinic puts the useful bedroom range at the cooler end of comfortable, and our own guide to the best temperature for sleep has the details. Darkness matters because light suppresses melatonin, which delays sleep onset and therefore pushes back the whole deep sleep window.

Being too hot was the third most common complaint in our survey at 24%, so it is worth checking your duvet tog and bedding before assuming the problem is something more complicated.

Sometimes the problem is less about adding good habits and more about removing something that is already interfering, such as:

• Alcohol: It gets you to sleep faster and then fragments the rest of the night, particularly the second half. The sedation is not the same thing as good sleep.
• Untreated sleep apnoea: Repeated airway collapse pulls you out of the deeper stages, so people with apnoea spend less time in N3 even when they are in bed for a full night. Read more about the symptoms and causes of sleep apnoea.
• Caffeine later than you think: It has a long half-life, so an afternoon coffee can still be active at bedtime. Our guide to caffeine and sleep covers the timings.
• Getting older: The most consistent age-related change in sleep is a steady decline in slow-wave sleep. This one is not a habit you can fix, and it is worth knowing before you conclude something has gone wrong.

Deep sleep has become a wellness product category, which means there is now a lot being sold on thin evidence. Three things worth knowing before you spend money:

• Chasing the number on your tracker: Consumer devices are reasonable at estimating when you were asleep and much shakier on which stage you were in. A study comparing 11 popular devices against clinical polysomnography found that agreement on sleep staging ranged from fair to moderate. The figure in your app is an algorithm that infers brain states from your pulse and movement, so it is worth reading as a trend over weeks rather than a verdict on last night.
• Pink noise machines: The laboratory studies behind the claims use closed-loop stimulation, where an EEG tracks your brain waves in real time and fires brief pulses of sound timed to the upswing of each slow wave. A speaker playing continuous pink noise all night is doing something else entirely. One recent trial found that continuous pink noise reduced REM sleep. Researchers have urged caution about nightly use until more work is done.
• Most supplements: The evidence for supplements raising deep sleep specifically is thin. Worth knowing that in the UK, melatonin is a prescription-only medicine rather than something you can pick up in a health food shop. Our guides to magnesium for sleep and natural sleep remedies go through what is and is not supported.

If you are consistently sleeping a reasonable number of hours and still waking unrefreshed for weeks on end, that is worth a conversation rather than another gadget. The same goes if you snore heavily, wake gasping, or your partner has noticed you stop breathing during the night, all of which point towards sleep apnoea and need proper assessment.

For persistent insomnia, the first-line treatment recommended in clinical guidance is cognitive behavioural therapy for insomnia, which works better over the long term than sleeping tablets. Our guide to insomnia and how to beat it covers what it involves.