If your child has said their back hurts, the mattress is worth checking, but it usually isn't the cause.
Back pain in children is less common than in adults, and when it does happen the reasons are more often a heavy school bag, hours hunched over a phone, a growth spurt, or a sport. The mattress matters, but it's one factor among several.
Here's how to work out whether yours is part of the problem, and what actually helps.
First, the important bit
Persistent back pain in a child should be looked at by a GP.
Unlike in adults, back pain in children is less often mechanical and more likely to warrant a proper look. That's not a reason to panic, but it is a reason not to spend three months trying different mattresses first.
See a doctor if the pain:
- Lasts more than a couple of weeks
- Wakes them at night, or is worse at night than during the day
- Comes with fever, weight loss, or feeling generally unwell
- Follows a fall or an injury
- Is in a young child, under about ten
- Affects how they walk, or comes with numbness or tingling
We sell beds, not medical advice. For anything persistent, the NHS is the right starting point, and your GP is the right next step.
When the mattress is likely to be the problem
There are a few clear signals.
The pain is worst on waking and eases within an hour. That's the classic pattern for a mattress that isn't supporting them. If it builds during the day instead, look at school bags and posture rather than the bed.
You can see a dip. Strip the bed and look across the surface in daylight. A visible body impression that doesn't spring back within a minute or two means the mattress has gone.
It's more than about seven years old. Children's mattresses generally need replacing every five to seven years, and often sooner because they've been outgrown.
They sleep better elsewhere. If they're fine after a night at a grandparent's house and sore again at home, that's a fairly direct answer.
You can feel the springs. Self-explanatory.
What actually supports a growing spine
Firmer is generally better than softer, up to a point. A mattress that's too soft lets the hips sink and the spine curve. A mattress that's too hard creates pressure points at the shoulder and hip. Medium to medium-firm suits most children and teenagers.
Support matters more than plushness. A thick pillow-top on a poor base feels comfortable for a fortnight and then sags. What you're paying for is what's underneath.
Depth is about body weight, not comfort. A 15cm mattress supports a child perfectly well. A heavier teenager benefits from more, which is one of the genuine advantages of a floor-level bed over a bunk.
The one that catches people out
On a bunk bed or high sleeper, you can't just buy a thicker mattress.
Raised beds have a maximum mattress depth, usually 15 or 16cm, because guard rails are designed to sit a set height above the mattress surface. Going deeper for comfort removes that clearance and the rail stops doing its job.
If your teenager is on a high sleeper and needs more support than a 15cm mattress gives, the answer is a different bed rather than a deeper mattress.
Which mattress
On a bunk bed or high sleeper — 15cm maximum
PocketRest 15, from £230
Pocket springs respond individually to body weight, which gives more targeted support than foam at the same depth. The one we'd suggest for a child who's uncomfortable on a raised bed.
ComfortSleep 15, from £160
Reflex foam, firmer feel. Good for younger, lighter children.
On a standard bed frame — no depth limit
MemoryTeen 18, from £260
Deeper memory foam, built for a heavier and taller body. Not suitable for a raised bed, but the better choice for a teenager on a normal frame.
Guardian Orthopaedic Sprung Mattress
Firmer sprung support in the traditional orthopaedic style.
Full depth mattresses for older teenagers and adults, where depth isn't restricted.
The things that aren't the mattress
Worth ruling these out first, because they're more likely and they're free to fix.
School bags. A bag carried on one shoulder, or over about 10% of body weight, is one of the most common causes of back pain in school-age children. Two straps, worn properly, both shoulders.
Screen posture. Hours looking down at a phone loads the neck and upper back considerably. Raising the phone rather than lowering the head is the whole fix.
Desk setup. If homework happens at a desk under a high sleeper, check there's room to sit up straight, and that the chair is the right height for the desk.
Growth spurts. Genuine, temporary, and not something a mattress solves. Muscles and ligaments catching up with bone growth causes real aches, particularly in the early teens.
Sport. Gymnastics, rugby, dance and rowing all put specific loads through the back. Worth mentioning to a GP if there's a pattern.
Not enough movement. Counterintuitively, sitting still is worse for backs than being active.
Making a mattress last
- Rotate head to toe every three months. Most children's mattresses are single-sided, so rotate rather than flip unless the label says otherwise.
- Check the base. A broken slat or a sagging bed base ruins a new mattress within months, and it's often the real cause when a mattress seems to have failed early.
- Use a protector. The main reason children's mattresses are replaced early is what's happened to them rather than wear.
More detail in our guide to how often to change a mattress.
Common questions
Can a bad mattress cause back pain in children?
It can contribute, particularly if it's old or sagging. But back pain in children more often comes from school bags, posture, growth or sport. If the pain is worst on waking and eases within an hour, the mattress is a likely factor.
What firmness is best for a child with back pain?
Medium to medium-firm. Too soft lets the spine curve; too firm creates pressure points at the hip and shoulder.
Should a child sleep on a hard mattress?
No. The old advice about a board under the mattress has long been superseded. Supportive is the aim, not hard.
Is memory foam or pocket sprung better for back pain?
Pocket sprung gives more targeted support at the same depth, which is why we'd suggest it on a raised bed where you're limited to 15cm. On a normal bed frame, either works, and depth matters more than type.
My teenager has back pain. Should I buy a thicker mattress?
Only if they're on a standard bed frame. On a bunk or high sleeper the depth limit is a safety figure and can't be exceeded.
How do I know if the mattress needs replacing?
A visible dip that doesn't recover, springs you can feel, more than seven years old, or they consistently sleep better elsewhere.
When should I see a doctor about my child's back pain?
If it lasts more than a couple of weeks, wakes them at night, follows an injury, comes with fever or feeling unwell, or affects how they walk. Back pain in young children in particular is worth a proper look.
Browse our kids' mattress range, or read the kids' mattress guide for sizes and depths.
