How to Choose a Baby Mattress: The Ultimate Guide

How to Choose a Baby Mattress: The Ultimate Guide

There’s nothing more important than keeping your baby safe - finding a comfortable and secure sleeping environment is a huge part of that. Babies sleep anywhere from 14-20 hours per day, so ensuring their cot or Moses basket has the right mattress support is essential. 

The question on every parent's lips: how to choose a baby mattress? Our definitive guide will provide everything from size and thickness to mattress type and safety measures to ensure your baby has the perfect sleeping conditions for that all-important growth and development.

What to Look for in a Baby Mattress

It’s important to remember the below 4 points when choosing a mattress for your baby. Ensure it is;

  • The correct size for the cot
  • Firm and supportive
  • Water-resistant and washable
  • Breathable and hypoallergenic

Step-by-step guide: Choosing a Mattress for Your Baby

Follow these 5 steps when considering a new baby mattress;

1. Measure the Length and Width of your Cot

Standard cot mattresses are required to be a minimum of 69.2 cm by 129.5 cm. The cot mattress must fit snugly. Getting the right size and shape of mattress is essential to avoid your baby's limbs becoming stuck around the edges. There should be no more than a 3cm gap around the edges or sides.

Here are some standard mattress sizes for babies and small toddlers;

Cot Mattress

Dimensions: W60 x L120 x D10

A cot mattress is designed for babies and to fit a standard cot.

Cot Bed Mattress

Dimensions: W69 x L139 x D10

Perfect for babies and small toddlers, a cot bed mattress is designed to fit into a larger cot bed.

2. Check the Thickness of the Mattress

It’s important to note that mattresses that are too thick pose a suffocation risk to infants as they can sink into the soft sleeping surface. A cot mattress should not be thicker than 6 inches.

3. Ensure the Mattress is Firm Enough

A baby mattress should be firm and provide good support. Press your hands into the middle and sides of the mattress, to see if the mattress conforms to the shape of your hand or springs back to its original shape right away. If the mattress moulds to your hand, it is too soft for your baby.

4. Choose a Mattress with Ventilation Holes

Ensure your mattress has good breathability to help your baby regulate their temperature. Research has shown that overheating is associated with an increased risk of SIDS. A breathable mattress where air can circulate will allow any perspiration to wick away from your baby, so their mattresses stay clean and dry.

5. Choose a Mattress with a Very Thick Cover

We recommend a cot bed mattress that includes a washable and waterproof removable cover. This will keep your baby's mattress clean and hygienic.

Types of Mattresses for Babies


Are foam mattresses good for babies?

Memory foam moulds to the contours of your baby’s body providing maximum levels of support and comfort whilst they sleep. The foam’s tight structure is very difficult for dust mites to penetrate, making memory foam mattresses the best at reducing allergy symptoms.

The foam works with your baby’s body to keep them in the correct anatomical position, aligning their neck and spine. This creates a deeper, more restful and restorative sleep. 

Pocket Sprung

Pocket sprung mattresses are structured with thousands of individual springs that are housed in their fabric pocket. This composition allows the springs to move independently, offering high-pressure support whilst your baby sleeps. 


A hybrid mattress is a combination of the much-loved memory foam and pocket sprung mattresses. A layer of foam on top of the independent springs creates the perfect environment for back support and babies sensitive to movement.

Top Tips for a Safe Night’s Sleep

Put your Baby to Sleep on their Back

To reduce the risk of SIDS: Sudden Infant Death Syndrome, a baby should be put to sleep on their back. Babies should sleep on their back to ensure they are unable to roll onto their tummy and subsequently smother themselves in blankets, or breathe in any vomit that they may bring up.

Only use a Fitted Sheet for the Cot

The safest sleeping environment is a fitted sheet on a cot mattress, with no other bedding or soft objects in the crib to prevent suffocation.

Keep Your Mattress Clean

All baby and child mattresses have an outside fabric layer and a waterproof side. Some may not be removable for washing, so remember to wipe clean these regularly.

Use a Hypoallergenic Mattress or Mattress Covers

A hypoallergenic mattress is designed to prevent allergic reactions. The mattress is tightly sealed to prevent dead skin cells and body oils from permeating into the material which prevents dust mites from penetrating the mattress. 

We offer hypoallergenic mattresses which are anti-allergy and anti-bacterial. Your mattress should include the following features to reduce the likelihood of allergic symptoms:

  • Dust mite-resistant materials
  • Anti-allergy covers

Memory Foam Warehouse’s Junior Mattresses

We strive to bring the best possible night’s sleep to your little one, every night of the week. After all, the more they sleep, the more you do too!

Here’s a closer look at the finer details of our junior mattresses;

CoolKids Range

When your baby is ready for a toddler bed, our CoolKids memory foam mattresses are a perfect choice for your child.

CoolKids Memory Foam Mattress

They feature a top layer of foam that sits on a durable and sturdy base, giving optimum support levels throughout the night.

As well as this, it offers;

  • Duo layer design
  • 4G technology
  • Hypo-allergenic materials
  • Dust mite resistance
  • Washable cover
  • Medium-soft firmness
  • CoolMax memory foam fibres

The fabric itself has an innovative cooling design that helps your child to stay dry throughout the night. Also, the cover is made from fast-drying, breathable fibres that reduce shrinkage and wrinkling even after multiple washes.

The CoolKids brand is famous for its breathability, keeping children cool and fresh throughout the night. It’s also highly luxurious, offering medium-level support.

It’s been designed and created in-line with UK regulations, ensuring your little one is safe in bed. For this reason, it has all the necessary ingredients of a good night’s sleep.

CoolKids Pocket Sprung Memory Foam Mattress

The 3cm memory foam layer provides comfort and support for your growing child and works in harmony with their body to ensure that they are sleeping in the correct anatomical position. 

Pocket springs provide even further support as they respond to changes in your child's sleeping position. Both of these elements work perfectly together and reduce the need to toss and turn, creating a deeper and more restorative sleep for their active mind and body.


Whatever your age, preference and requirements, browse our full collection of memory foam mattresses to find the right fit for you.


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