The Best Sleeping Position for Back, Hip and Neck Pain (And the One Pillow Most People Are Missing)

Most people asking “what’s the best sleeping position?” are really asking a different question: why do I wake up sore when I went to bed fine?

The honest answer is that position alone doesn’t fix it. Side sleeping is the position most often recommended for back, hip and neck pain — and it’s the right recommendation — but side sleeping done badly is worse than back sleeping done well. The difference between the two isn’t your body. It’s what’s supporting it.

There are two support points that matter, and almost everyone gets one of them and ignores the other.

Why side sleeping is the default recommendation

Side sleeping wins for most people for three reasons that have nothing to do with comfort preference:

It keeps the spine in a neutral line. Lying on your side, the natural curve of your lower back is preserved rather than flattened (back sleeping on a soft mattress) or hyperextended (stomach sleeping).

It opens the airway. Side sleeping reduces snoring and obstructive events compared to sleeping flat on your back, where the tongue and soft palate fall backward under gravity.

It takes rotational load off the neck. Stomach sleepers have to turn their head 80–90° to one side for six to nine hours a night. There is no version of that which is good for the cervical spine.

So far, so standard. Here’s the part that gets skipped.

The problem side sleeping creates

Lie on your side without support and watch what happens to your top leg.

It drops. It slides forward and down across the bottom leg, and because your femur is attached to your pelvis, the pelvis follows it — rotating forward. Your shoulders stay roughly where they are, because they’re pinned by the mattress and your bodyweight.

That mismatch is the whole problem. Your pelvis is rotated one way, your ribcage is rotated the other, and the twist has to be absorbed somewhere. It gets absorbed by the lumbar spine, the sacroiliac joint, and the IT band running down the outside of your top leg.

Six to nine hours of low-grade torque. Every night. This is why so many side sleepers wake with:

• Lower back stiffness that eases after 20 minutes of walking around
• A deep ache in the top hip — often mistaken for arthritis or bursitis
• One-sided sciatic-type pain that’s worse in the morning
• Knee discomfort on the inside of the bottom knee, where the top one has been grinding against it

None of that is caused by side sleeping. It’s caused by unsupported side sleeping.

The fix: a pillow between your knees

Putting a pillow between your knees does one mechanical job, and it does it well: it holds your top leg at roughly the same height as your hip, so the pelvis stays stacked rather than rotating forward.

Stack the pelvis and the twist disappears. That’s it. It’s not a comfort accessory — it’s a structural correction, and it’s the single highest-return change most side sleepers can make.

If you’ve read our best pillow for hip pain guide, this is the same principle applied one level down the chain.

How to actually position it

The details matter more than people expect. Most of the benefit is lost if the pillow is in the wrong place.

1. Start on your side with knees slightly bent. Not curled into a full fetal position — that flexes the lumbar spine and can make disc-related pain worse. Think 20–30° of bend.
2. Place the pillow between the knees and the lower shins. This is the mistake almost everyone makes: a pillow at the knees only, with the ankles left touching. That still lets the lower leg drop and the pelvis rotate, just less. Support from knee to ankle.
3. Check the height. Your top knee should sit level with — or very slightly above — your top hip. If the knee is dropping below hip height, the pillow is too thin. If your top leg is riding up above the hip, it’s too thick, and you’ll get lateral hip tightness instead.
4. Keep both legs roughly parallel. If the top leg is still sliding forward past the bottom one, you’re half-rotated and the pillow isn’t doing its job. Pull it back into line.
5. Hug a pillow with your top arm (optional, but it helps). It stops the top shoulder rolling forward, which is the upper-body version of the same rotation problem.

What kind of pillow

You don’t need a specialist product for this to work, but firmness matters a lot more than shape:

• A firm standard pillow — folded once if it’s soft — works fine and costs nothing. Downside: it compresses overnight and shifts out of position.
• A dedicated contoured knee pillow — hourglass-shaped memory foam with a strap. Holds height overnight and doesn’t migrate. Worth the €20–30 if you move a lot in your sleep.
• A body pillow — supports knees, shins and top arm in one piece. Best option for pregnancy, and for people who wake up half on their stomach.

Avoid anything squashy. If it compresses to half its height under your leg’s weight, it’s not supporting anything by 3am.

The other half: what’s under your head

Here’s where most people’s setup falls apart. They fix the knees, feel a partial improvement, and conclude that side sleeping “just doesn’t work” for them.

The knee pillow controls the pelvis. Nothing is controlling the neck.

When you’re on your side, there’s a gap between your ear and the mattress equal to the width of your shoulder — around 10–15 cm for most adults. A pillow needs to fill exactly that gap so your head stays in line with your spine.

• Too flat → head drops toward the mattress, neck bends downward, and you wake with pain on the upper side of your neck.
• Too thick → head is pushed up, neck bends the other way, and you get pain on the underside plus a numb arm.

You can test this in ten seconds: lie on your side in your normal setup and have someone look at you from behind, or take a photo. Your nose, chin, breastbone and navel should form a straight line running parallel to the mattress. If your head is tilted either way, your pillow height is wrong — and no amount of leg support will fix a neck problem.

This is the reasoning behind contoured designs like the Derila, which use a raised side wall specifically to fill the shoulder gap for side sleepers, with a lower centre channel for the nights you roll onto your back. Whether that specific pillow suits you depends on your shoulder width and mattress firmness — we’ve covered the honest case for and against it, including who should skip it.

The principle stands regardless of brand: two support points, not one. Neck gap filled, knees stacked.

The complete side-sleeping setup

Run through this once tonight:

• On your side, knees bent 20–30° (not curled tight)
• Pillow between knees and shins, top knee level with top hip
• Head pillow fills the ear-to-mattress gap completely
• Nose, chin, sternum, navel in one line
• Top arm supported — on a pillow, not draped across your body
• Bottom shoulder pulled slightly forward, not crushed under you

That’s the whole system. It takes about 90 seconds to set up and it’s the closest thing to a free fix that exists for mechanical sleep pain.

If you’re not a side sleeper

Back sleepers: put a pillow under your knees instead. Lying flat pulls the pelvis into an anterior tilt and hyperextends the lower back — a wedge or folded pillow under the knees releases the psoas and lets the lumbar spine settle. Head pillow should be thinner than a side sleeper’s, since there’s no shoulder gap to fill.

Stomach sleepers: the honest answer is to stop, and we know that’s not very useful. If you can’t, put a thin pillow under your pelvis and hips to stop the lower back sagging, and use the thinnest possible pillow under your head — or none. Then work on transitioning to your side, using a body pillow to hug. It gives your arms and top leg somewhere to go, which is usually the reason stomach sleeping feels comfortable in the first place.

Recliner sleepers — recovering from surgery, or managing reflux — have a different set of trade-offs entirely. We covered those in the recliner sleeping guide.

Common mistakes

Giving up after two nights. Your body has adapted to its current position over years. A corrected position genuinely feels wrong at first — that’s the adaptation, not a sign it isn’t working. Give it two weeks before you judge.

Using a pillow that’s too soft. It compresses to nothing by the middle of the night and you wake up in the same rotated position you started with, wondering why nothing changed.

Fixing the knees and ignoring the neck. Half a system produces half a result, and people usually conclude the whole approach is a bust.

Chasing the “correct” position instead of the right support. There’s no universally correct posture. There’s your body, your mattress, your shoulder width — and support that matches them.

When position isn’t the problem

Be realistic about what a pillow can and can’t do. Sleep position corrections help pain that is mechanical — the kind that’s worse on waking, eases with movement, and varies with how you slept.

Get it checked if your pain:

• Wakes you in the night rather than being there on waking
• Doesn’t ease at all with movement or position change
• Comes with numbness, weakness, or loss of bladder or bowel control
• Is accompanied by unexplained weight loss or fever
• Has been steadily worsening for more than a few weeks despite changes

Those patterns aren’t positional, and no pillow addresses them.

Frequently asked questions

Can I use a pillow between my knees while pregnant?

Yes — it’s usually recommended, particularly left-side sleeping in the second and third trimesters. A full body pillow tends to work better than a small knee pillow as pregnancy progresses, since it supports the bump as well.

Does it work if I switch sides during the night?

Yes, though you’ll have to reposition the pillow each time. A strapped knee pillow moves with you; a loose one usually ends up on the floor.

How thick should the knee pillow be?

Enough that your top knee sits level with your top hip. For most adults that’s 15–20 cm of uncompressed foam. Wider hips and narrower waists need more.

Will this help sciatica?

It helps the type of sciatic irritation caused by rotation and nerve compression during sleep — which is a real and common contributor if your symptoms are worst in the morning. It won’t resolve a herniated disc.

Can I just use a rolled-up blanket?

Short term, yes. It compresses faster than foam, so it drifts out of position, but as a test to see whether the approach helps you at all, it’s a perfectly reasonable free trial.

This page contains affiliate links. If you buy through our link we may earn a commission at no extra cost to you. Our guidance is based on product research and verified buyer feedback; vendors have no input. This article is general information, not medical advice — if your pain is severe, persistent or accompanied by the warning signs above, see a clinician.