Your child gets a new mattress; guests can have the spare
Buy your child a new mattress with a proper support core and enough cushioning to feel comfortable. That's my rule even when there's an older sibling's mattress available. I'm all for passing things down, but I draw the line at a sleeping surface with somebody else's dip in it. A mattress that has already sagged won't become level when you put a lighter child on it.
A used mattress can also come with an unknown history, or springs that have lost their support. A clean cover tells you very little about either. Even when you know exactly where the mattress has been, check its shape: a hollow where another person slept is enough reason to rule it out for your child.
New needs to mean more than unused, though. The thinnest foam pad in the range doesn't become a proper everyday mattress because someone has put a cheerful cover on it. Children get plenty of cheerful covers; the bit underneath deserves some attention. Look for a stated pocket-spring or foam construction, then check its suitability for the bed and the maker's care instructions.
On a tight budget, put the money into the mattress before decorative extras. A plain frame with sound support is a perfectly sensible choice. My spare-room standards are considerably more relaxed, but the mattress your child sleeps on every night is the purchase I want you to get right.
Children need more sleep, but a mattress is only one part of it
Give your child enough opportunity to sleep; buying a mattress is only one part of that. The National Sleep Foundation's eighteen-member expert panel, reported by Hirshkowitz and colleagues in 2015 , recommended 9 to 11 hours a night for school-age children, against 7 to 9 for adults. These are consensus recommendations for healthy people, not findings from a trial.1
In a 2016 systematic review, Chaput and colleagues brought together 141 articles covering 592,215 children and young people aged 5 to 17 across 40 countries.2
“ Overall, longer sleep duration was associated with lower adiposity indicators, better emotional regulation, better academic achievement, and better quality of life/well-being.
My practical view is to get the bedroom basics sorted before buying anything with "sleep technology" printed across it. Keep the room dark and comfortably cool, and give bedtime a regular place in the evening. Blackout blinds would be my first choice for a bright room. You don't need to turn bedtime into a wellness project with its own shopping basket.
A comfortable mattress belongs alongside that routine. It gives your child a suitable surface to sleep on, but there's no reason to choose a mattress by promises about school performance or development. Choose it by fit, construction and how comfortable your child finds it.
A light child needs give, and the bed sets the depth limit
Start a small, light child on a medium tension, then check the mattress fits the frame and stays within its depth limit. A child puts less weight into the mattress than an adult, so they sink less. The shoulder and hip need some give. To a five-stone child, a firm or extra-firm mattress can feel brutally hard, however approvingly a salesperson says "supportive".
I work from the body using the mattress before the preferred sleeping position. For a light child, that means a softer starting point than my usual adult recommendation. A heavier or older child can move towards medium-firm, particularly if they sink too deeply into a medium. Treat those descriptions as starting points: brands use firmness labels differently, which is a bloody nuisance when you're trying to compare them.
These are my shopping starting points, not clinical weight thresholds. Dimensions are UK bed-size conventions; measure the actual frame before ordering.
Your child or bed What to look for What to check A small, light child, such as a five-stone sleeper A medium feel with cushioning at the shoulder and hip They should get some give without lying in a hollow A heavier or older child Try medium-firm alongside medium Choose by their comfort and how far they sink Most children's rooms UK single: 90 by 190 centimetres Enough floor space and growing room in the bed An older child with room for more width Small double: 120 by 190 centimetres The extra width must leave usable space around the bed A compact room or cabin bed Compact sizes include 75 by 190 or 90 by 175 centimetres The exact internal dimensions; compact sizes are not interchangeable A bunk, cabin bed or mid-sleeper A mattress within the bed's marked maximum depth The depth mark and the bed manufacturer's instructions
A single suits most children's rooms. A small double is lovely when the child's age and the room suit it, but it adds width without adding length. Measure the space with drawers and doors open. The beautifully styled bedroom photo rarely includes somebody trying to get a clean sheet out of the wardrobe.
Never exceed the maximum mattress depth marked on a bunk bed, cabin bed or mid-sleeper. The mattress must leave the guard rail well above the sleeping surface. Most of these beds need a shallow mattress, so deeper is no advantage. Check the depth before ordering, including whether the instructions allow any extra layer.
The base needs checking too, especially on a second-hand frame. Look for broken or loose slats and keep gaps to about seven centimetres at most, or closer if the mattress maker requires it. A new mattress still needs proper support underneath. For a younger child's bed change, our toddler mattresses are a useful place to look; for an older child's changing size, compare our teenager mattresses .
Choose a proper core and make accidents easy to clean up
Choose pocket springs or good-density foam, and put a washable, waterproof protector on before the first night. Pocket springs are my preference, though a well-made foam mattress is a sensible option. A modest pocket-spring count is fine for a child's weight. You can safely decline the spring-count competition; there are enough numbers in the school newsletter.
Open coil would never be my choice for a child's everyday bed. Its connected springs pass movement across the surface, and I prefer the separate support of pocket springs. With foam, check what the maker says about the core and its density. A decorative cover and a thin pad underneath don't amount to a good everyday mattress.
Memory foam runs warm, so I wouldn't make it the default for a child whose room is already warm. Cooling names don't change my preference for a more breathable construction in that situation. Compare the fillings and core before getting distracted by the name. Some mattress names sound as though you're choosing a gaming laptop.
This is one of the few places where I'm firmly in favour of a protector. During the accident years, choose one that's both washable and waterproof, and check its washing instructions before you buy. Wash bedding weekly and air the room. A spare protector makes an overnight change much less of an operation, especially when you're doing it half asleep.
Rolled delivery is useful when access is awkward. Give the mattress the maker's full expansion time and air the room before use. Keep the packaging instructions until it's ready, and judge the feel over the first fortnight instead of treating the first evening as conclusive. The initial feel can change as the mattress settles; a visible defect or unsafe fit needs addressing straight away.
Replace the mattress when there's a lasting dip or your child's feet reach the end. A mattress that has been wet through and hasn't dried properly also needs replacing. After a long illness with heavy sweating, replacement is appropriate if you cannot get it aired fully dry. Age alone is less useful than its shape, condition and remaining length.
For a baby, the mattress should be firm, flat and waterproof, fit the cot with no gaps, and be new if possible. Follow the NHS and the Lullaby Trust's safer sleep advice for everything else about a baby's sleep.
Leave the dipped spare and the over-deep mattress out of the basket
Rule out these choices before comparing the remaining mattresses. "They'll grow into it" is fine for a slightly roomy jumper; I don't accept it for an uncomfortable mattress. And the bargain is considerably less charming if you have to arrange a return because it sits above the bed's depth mark.
The older sibling's mattress with a dip: your child would still be sleeping on an uneven surface.A firm "orthopaedic" mattress for a five-stone child: the word is unregulated, and the hard feel can be entirely wrong for a light body.A mattress deeper than the bunk or cabin bed allows: it reduces the guard rail height above the sleeping surface.The thinnest foam pad because it's "only for a child": choose a proper support core and suitable cushioning.No waterproof protector during the accident years: keeping liquid out is far easier than drying a soaked mattress.
