How to Choose a Kids Mattress

At Happy Beds, we have a range of mattresses that are perfect for kids. Here are some of our most popular kids mattress sizes.

What size is a toddler mattress?

A toddlers mattresses is 70cm x 140cm. They're designed to fit perfectly within a toddler bed.

What size is a shorty mattress?

A shorty mattress is 75cm x 175cm. Shorty mattresses are just what they sound like - a little shorter, to support littler bodies! Shorty mattresses are an excellent choice for smaller kids.

What size is a small single mattress?

A small single mattress is 2’6” x 6’3”. If your kid needs something bigger than a toddler mattress but isn't quite ready for a single, or if you're trying to save space in a smaller bedroom, a small single mattress is ideal. It’s the same length as a regular single but slightly narrower.

What size is a single mattress?

A single mattress is 3’ x 6’3”. When your kids are beyond the toddler stage, you may prefer to sleep them in a standard single bed. A single bed will give them plenty of wiggle room as they grow.

What size is a small double mattress?

A small double mattress is 4’ x 6’3”. A small double is a great compromise if you have an older kid or teenager who wants a little more room. They’re slightly narrower than a standard double but wider than a single.

Of course, if you want an even bigger mattress for older kids, you can treat them to a double, king, or even super-king. Explore our overall mattress size guide for more information on our bigger mattresses.

If you're choosing a baby mattress, we'd always recommend a firm option to begin with. You'll also need a cot-specific mattress. It's incredibly important to make sure your baby mattress is perfectly sized for the cot you're using, with no gaps around the sides that the baby could fall down. Always double-check measurements to make sure your baby mattress is safe for use.

Your child will likely move into a toddler bed from around a year onwards, which allows more room than a standard cot. Again, at this age, you'll want a relatively firm mattress to provide support for your tot as they grow. If your child overheats a lot during the night, a ventilated mattress with cooling properties is ideal.

At around 4 or 5, most kids will make the move from a toddler bed to a regular kids bed. The size of this bed is totally up to you. Single beds are standard, but you can also opt for a small single or a shorty bed if you're looking to save space in a smaller bedroom.

When it comes to mattresses, always make sure the size aligns with the bed you've chosen. Medium firm is a good option for younger kids, and you can begin exploring different mattress options such as reflex or memory foam as your kid grows older. If your kid is a fidgeter and moves around during the night, foam mattresses can be a good option to keep them comfortable and steady.

When it comes to mattresses for teenagers, it mostly comes down to personal preference. They're still growing, so they'll need a supportive mattress, but you can choose from a range of different types depending on their sleeping preferences. Latex foam mattresses are a good choice for most teenagers, as they provide support while adapting to the body - ideal for handling those growing pains!

The way a teenager sleeps can also come into play. Stomach sleepers are best off with a firm mattress, as it keeps the spine aligned, while side sleepers can opt for medium to soft mattresses if they prefer. For more tips and advice for buying a mattress for a teenager, check out our Mattress Guide for Growing Teens.

We're often asked whether it's better for kids to sleep on a firm mattress. Generally speaking, yes, it is!

Young kids need a firm mattress to help support them as they grow. Particularly at the baby and toddler stage, their neck and spine are still developing, so they need to be adequately supported throughout the night. A firm mattress keeps the spine in a neutral position, minimising stress and reducing pressure.

When exploring mattresses, you'll find a range of different types available. If you're wondering which to buy for a child, we've detailed some of the most popular options and their benefits.

Open coil spring kids' mattress

An open coil spring mattress is a long-lasting option, making it great for growing kids. The spring design helps support their spine and distributes body weight evenly for a comfortable night's sleep.

Pocket spring kids' mattress

A pocket spring mattress is slightly more cushioned than open coil, meaning it's a little more responsive. Again, the spring design means this long-lasting mattress offers high levels of support.

Memory foam kids' mattress

Memory foam adapts to the sleeper's shape, making it an extremely comfortable option. Memory foam is excellent for older kids and teenagers but should be avoided for babies, toddlers and younger kids.

Reflex foam kids' mattress

Reflex foam is lighter than standard memory foam, with a solid, firm base that provides a great level of support. Again, it's a better choice for slightly older kids.

Should I buy a foam or spring mattress for a baby?

We'd always recommend buying a spring mattress for a baby. As we've mentioned, babies' and toddlers' spines are still developing, so a spring mattress is ideal as it provides the optimum level of firmness and support they need.

Are memory foam mattresses safe for children?

Memory foam isn't recommended for babies, toddlers and younger children who are still growing, as it moulds to the body and may not give the level of support they need while their spine is still developing. For this reason, pocket sprung or open coil mattresses are best for growing kids.

If you're looking for a mattress for an older child or teenager, memory foam is a perfectly safe (and comfortable!) option.

An important thing to keep in mind when shopping for a kids' mattress is safety. As we've mentioned, it's vital for babies and toddlers that their mattress fits perfectly in their cot or bed, with no gaps around the edge, so always double-check measurements before you buy.

For older kids who may want a high sleeper or a bunk bed, you always need to make sure the mattress they're using is totally safe. For higher beds, you need to ensure the height of the mattress doesn't reach above any safety rails, or you'll risk falls. Again, double-check all measurements before buying a mattress for a high bed, to make sure it's safe for use.

Firmness is the priority when purchasing your child’s first mattress, but why? Well, during the night, a toddler’s spine can grow up to 1.5cm as the intervertebral discs in between their vertebrae fill with water. As this process takes place, both the spine and neck should be firmly supported and held in a neutral sleeping position. Basically, there’ll be no starfishing as of yet. The mattress itself must be firm enough to provide this support but soft enough that your child is actually comfortable staying in roughly the same position throughout their nightly rest.

Alongside this, keeping cool also has a huge effect on how your child develops in their first bed. If you are considering some form of orthopaedic mattress, it's important to remember that memory foam uses stored body heat to activate its moulding system, which can, in turn, lead to a rather warm foundation for your child to sleep on. So, maybe hold off with the memory foam for a few more years!

If yours is a relatively cold room, then no problem, but if the room does get warm in summer, a latex mattress would provide this function without that extra heat. However, we should also state that while orthopaedic mattresses are wonderful for adults who suffer from joint pain or a bad back, that very same moulding function can lead to a lack of stable firmness that is necessary for a growing spine.

If you're looking for a new kids' mattress, you've come to the right place. Whatever type of mattress you settle on, our Happy Beds collection is full of comfortable options that will ensure your little ones get a dreamy night's sleep.