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Cot Bed Mattresses

Our cot and cot bed mattresses are not only safe and secure, but comfy and supportive. Let your baby sleep softly - so you can too - with our range of children's mattresses.

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Trustpilot Star rating

Based on 21,218 reviews

Trustpilot Star rating Verified

Great service, delivery within 24 hours, delivery men were on time and helpful. Mattress is super comfy, great value for money.

Peter 20th Feb
Trustpilot Star rating Verified

Easy to order and its a really next day delivery. Drivers was on time so dont need to all day waiting.

Marite 20th Feb
Trustpilot Star rating Verified

First finding a quality mattress that can be delivered so quickly.The delivery went very smoothly, fitted in with my timing. The mattress was exceptional, really great quality and so comfortable. I am really glad I chose my product through this supplier. Especially as it's a risk for an important purchase. Thank you

Farra Pedley 20th Feb

Help & Buying Guides

How to choose the right cot bed mattress

Babies can sleep for up to 20 hours a day in the first months, so it’s vitally important that a baby mattress is specifically designed to give them the comfort and support that they need. Because babies sleep on their back, a cot mattress needs to be firm but without being too hard.

Babies cannot regulate their body temperature as effectively as an adult, so our baby mattresses are designed to let the air flow pass through easily, keeping baby cooler and more relaxed.

They also need to be super-hygienic, which is why all of our baby mattresses are designed with removable outer covers and wipe-clean, waterproof inner covers. Simply remove the outer cover and pop in the wash, and wipe clean the inner cover if there’s a little night-time accident.

Toddlers can be restless, so our cot bed mattresses are designed to cope with everything from excited jumping up and down to snuggling with Teddy for a dreamy night’s sleep. Cot bed mattresses are usually slightly larger but have the same hygiene features as a baby mattress.

Can you get hypoallergenic baby mattresses?

Very young children can be incredibly sensitive to allergens and chemicals. To give you total peace of mind and to help your child get a great night’s sleep, our cot mattresses are chosen for their purity and hygienic design. Look for an anti-allergy cot mattress that’s free of chemicals that can trigger a reaction. Hypoallergenic cot mattresses also prevent the growth of mould, are anti-bacterial and anti-microbial, lessening the chances of causing an asthma attack or eczema flair-up.

At MattressNextDay, we want everyone to have a great night’s sleep. Our selection of cot mattresses and cot bed mattresses are perfectly suited for our younger customers. Browse our selection and remember that every mattress benefits from free next-day delivery, so your little one could be having sweet dreams all night long!

Do all cots have the same size mattress?

The most common size for a cot bed mattress is 70cm wide by 140cm long. Mattresses of this size should fit most cot beds and fit snuggly into a standard frame with no gaps around the edges that could pinch little fingers.

There are some mattresses that are designed to fit a slightly smaller cot bed at 60cm by 120cm, so it is important to measure your bed carefully to ensure you buy the correct sized cot bed mattress. 

What size cot mattress do I need?

The most popular size for cot mattresses is 120cm x 60cm, while for cot bed mattresses, which are designed for older toddlers, the common dimensions are 140cm x 70cm. These two sizes should fit the majority of both cots and cot beds without being pushed up at the ends or squeezed on the sides. The mattress should lay flat to make sure your little one has a comfortable night’s sleep.

Our top tip: Measure twice, buy once! Remember to measure the interior dimension of your crib, cot, or cot bed (and not the exterior) to ensure your mattress fits perfectly.

Mattress sizeDimensions
Cot Mattress120cm x 60cm
Cot Bed Mattress140cm x 70cm

What type of cot mattresses are available?

Just like adult and kids mattresses, cot bed mattresses are available in both pocket sprung and memory foam designs. The majority of baby mattresses are made from memory foam, but some also incorporate hybrid designs with pocketed springs making up the core of the mattress for a firmer feel.

The benefits of a cot mattress that’s pocket sprung include a more responsive feel, the elimination of movement transference and vibrations, and a cooler, fresher feel thanks to the increased airflow through the springs.

Memory foam mattresses for cots are primarily made from Reflex foam, which is denser and firmer than standard memory foam. They can be a little warmer than pocketed sprung options, so our advice is to look at either a pocket sprung cot mattress or a hybrid option that combines the best of both springs and memory foam.

For more information, read our guide on how to buy a cot bed mattress.

How thick should a cot bed mattress be?

The recommended thickness for a cot bed mattress is at least 10cm. this provides enough padding and support for your baby. Just as in an adult mattress, it should be sufficiently thick enough to transfer the child’s weight effectively if they wriggle or move in the night. The mattress should also be thick enough to ensure that the weight of the child doesn’t cause the mattress to sag.

As the average cot bed mattress will spend around three to five years being used, and taking into account that the child’s weight will more than triple during that time, it will need to be thick and firm enough to support a growing child through all stages of development.

Look out for dual mattresses that have one side designed specifically to be comfortable for babies, and the other that is more robust and suitable for larger toddlers or children.