The best mattress firmness for children by age

Choosing the correct mattress firmness

Children weigh significantly less than adults, so logic would dictate that buying them a standard mattress won’t work well. But it’s the opposite — a single mattress with a medium or medium-firm ‘feel’ is more than suitable for most kids.

Mattress firmness is subjective because the heavier you are, the softer a mattress feels as your body compresses the support system. So, a medium or medium-firm surface might feel solid to a child, but it provides excellent support.

Most children’s mattresses have a medium or medium-firm feel because the support system is good from age five to adulthood. Plus, more support means a more durable mattress to withstand bouncing and messing around.

However, you can also get soft and medium-soft mattresses, which are much cushier and provide fine support but are less durable.

Age 1-4

Your child will be in a cot or cot bed between these ages, and mattresses for them don’t typically have firmness ratings. They are, however, medium-firm or firm when unlabelled to prevent sinking and suffocation.

You should shop for a cot/cot bed mattress based on its composition (pure foam or sprung) and thickness. A 10-15cm pure foam mattress will serve your child perfectly until they can move up to a single or small single bed.

If you move your child to a full-size bed, age two and a half is a good benchmark — look for a medium or medium-firm mattress.

Age 5-10

At this age, your child is ready for a full-size bed and can enjoy any adult-sized mattress that is medium-soft, medium-, or medium-firm.

A medium-soft mattress might sink, which might concern you — in which case, a medium mattress is a good compromise. The safest choice is a medium-firm mattress, as the surface won’t allow dips and deformities.

Pocket springs are the best composition for a child’s mattress. They are more durable than open coils and pure foam options. The downside to pocket springs is that they are bouncy, and your kid might find jumping on them irresistible!

If your kid has bunk beds, look at pocket spring and open coil mattresses, but ensure the top bunk mattress is slim enough for the top guard rail to work.

Age 11-16

Older kids do best with the most durable surface possible without making their bed rock-hard. Medium-firm is the best firmness for your kid, as the surface will be comfortable without crumpling under the first misuse.

Mattresses with a memory foam top layer or a pillowtop filled with foam or fibre are great options for preserving that soft, cushioning feel.

Older teenagers

Older teenagers can enjoy any mattress as you don’t have to contend with them jumping on the bed and breaking a soft support system.

You’ll find that the lighter your kid is, the softer the mattress should be, making medium-soft a perfectly good choice for teenagers under 135 lbs.

Teenagers who weigh more than 140 lbs are best off with a medium mattress, and those over 190 lbs should consider medium-firm mattresses.

Your biggest considerations

Toddlers and children sleeping in a cot bed just need a cot or cot bed mattress — they are usually medium-firm by default.

Younger children will adore a soft mattress, but if their surface is so soft that it restricts mobility, there’s a risk of suffocation. We recommend a medium or medium-firm (ideally medium-firm) mattress for them.

Older children could easily destroy a soft mattress by jumping on it, so a firmer option could save you money (and frustration). A medium-firm mattress is perfect, but a medium one is fine if your kid takes it easy.