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22 December 2020

Top five cot mattresses for 2021

Discover our pick of the best cot mattresses available to buy, based on the results of our rigorous lab tests.
SM
Sam Morris

When cot mattresses cost anything up to £300, you want to know your hard-earned cash gets you the best for your baby.

A great cot mattress should be firm enough to provide great body support for your baby as their bones rapidly grow, durable enough to last until they're ready to move on to a junior bed, and completely safe so you know your child is at no risk. 

With our most expensive Don't Buy costing £250, and our cheapest Best Buy £45, we have found that quality and safety does not always go up with price.

Our robust and impartial lab tests have uncovered the very best cot mattresses on the market – and found those that are unsafe to use.

Below, we have picked out our top five highest-scoring cot mattresses that are available to buy in 2021, so you can be sure you are buying the best.

All our top five cot mattresses have performed well in our body support, durability, and safety tests. 

Only logged-in Which? members can view our recommendations in the table below. If you're not yet a member, join Which? to get instant access.

The five best cot mattresses

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81%
Best Buy
£95.00
Reviewed

We were very impressed with this cot mattress. It is firm and durable, providing the body support needed for your growing child. Not only this, but it is well ventilated and easy to clean. Scoring highly across our test results, we highly recommend this cot mattress.

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79%
Best Buy
£45.00
Reviewed

This high scoring foam cot mattress is well priced, comes with two covers and is reversible. It scored high in our durability and body support tests - being it should last until your child is ready to move to a junior bed. On top of this it is also reversible! This cot mattress provides excellent value for money.

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79%
Best Buy
£70.00
Reviewed

This foam cot mattress is particularly, and it offers good body support to babies and toddlers. It's very easy to clean, though it's worth noting that it loses firmness over time, so it's not ideal to reuse with a second child. With it's reasonable price and features, this cot mattress is a great option to consider if purchasing from new.

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77%
Best Buy
£69.99
Reviewed

This cot mattress excels in terms of firmness and body support. It's durable, meaning it will last for at least three years with only a minimal change in height and firmness. The cover is easy to remove and clean, although you might want to invest in an extra waterproof cover. This cot mattress performed well across our testing.

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76%
Best Buy
£129.00
Reviewed

There’s plenty to like about the Ikea Drömmande cot mattress, not least the fact that it’s firm, supportive and held up well in our durability tests. There’s also a handle to help you move it, and a removable washable cover to keep it fresh. Scoring highly across our tests, the Ikea Drömmandecot mattress is definitely one to consider.

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Table last updated 22 December 2020.

Not found the right cot mattress? Discover all of our Best Buy cot mattresses.

The cot mattresses to avoid

We test all our cot mattresses to the British Safety Standard  BS EN 16890:2017. While meeting this standard is voluntary, manufacturers are strongly encouraged to meet it in order to minimise risks and hazards for babies and young children.

Below we have highlighted any cot mattresses that have failed our safety tests to such an extent that we have placed a safety alert on them. You should not buy these cot mattresses.

John Lewis Dual Purpose Spring Cotbed

John Lewis Dual Purpose Spring Cotbed

Safety alert
£200.00
Reviewed

Our tests indicate this mattress poses a potential suffocation risk if a young baby turns onto his or her front and is not able to turn back the other way. This is an issue not when new, but after several years of use. This mattress passed all relevant safety tests at launch, but John Lewis & Partners is recalling the Dual Purpose Spring Cotbed mattress after conducting their own retests of the product. Contact them on 01698 545 160 to arrange a replacement and a refund.

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Babydunlopillo Safer Sleep Cot Bed Mattress

Babydunlopillo Safer Sleep Cot Bed Mattress

Safety alert
£250.00
Reviewed

Our tests indicate this mattress poses a potential suffocation risk if a young baby turns onto his or her front and is not able to turn back the other way. This mattress also failed the shrinkage test. The cover shrank after two washes, which creates a possible injury risk as the contracted mattress could lead to an unsafe gap between the mattress and the cot where your child could get trapped. Both tests are part of the latest British safety standard (EN 16890:2017). This cot mattress does not claim to adhere to this voluntary standard.

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Stokke Home Bed Mattress

Stokke Home Bed Mattress

Safety alert
£87.00
Reviewed

While this cot mattress passed safety standards in force when it first went on sale, it failed our test which determines whether a mattress is firm enough to prevent a baby younger than six months old from being smothered if they roll on to their face while sleeping. Safer Sleep charity The Lullaby Trust recommends a firm and flat mattress, as there is evidence to show that soft sleep surfaces are associated with a significant increase in the risk of Sudden Infant Death Syndrome (SIDS). In 2020 Stokke told us it has updated this mattress and the old product is no longer in circulation, but we haven't verified this with our testing. We'll be keeping it as a Don't Buy until we're sure this version is no longer on sale. If you own this mattress Stokke says that customers can contact its customer service department for a refund if they are dissatisfied with it.

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Table last updated 22 December 2020

Why is it so important to test cot mattresses for hazards and risks? Read our full cot mattress safety guide.

How we test our cot mattresses

All our cot mattresses are put through robust, extensive and independent testing, all so you can have complete confidence in our results.

A cot mattress needs to provide great body support for your growing child. We use a 12kg and a 20kg dummy to test how well the cot mattress supports a baby and a toddler.

If the mattress claims to be reversible, we test each side of the mattress with both dummies. This body support test shows us if the mattress keeps your child's body totally supported – helping them stay settled while asleep.

We conduct our safety tests to the BS EN 16890:2017 safety standard for cot mattresses. This means we test for:

  • Suffocation hazards We test the firmness of each mattress to ensure it doesn't pose a suffocation risk. We also check that labels and decals cannot be detached or loosened, and that a child cannot accidentally access the inner materials of a mattress.
  • Choking hazards Any part considered grippable by a child and small enough to be potentially swallowed poses a choking risk, so we test to ensure nothing can easily detach or break away from the mattress.
  • Entrapment hazards We measure cot mattress dimensions to ensure they'll fit smugly and flat into the cot beds their made for. This is to ensure no gaps larger than 3cm can form between the mattress edge and cot bed. Gaps could lead to a child trapping a part of their body and injuring themselves.
  • Sharp edges We check the mattress for sharp edges or points both at the start and end of testing to ensure there's no feature your child can cut or hurt themselves on.

A cot mattress needs to last for at least two to three years of continual use – right up until your child's ready to move on to a junior bed. Our durability testing replicates two to three years of jumping, sitting and sleeping on the mattress.

We then record any changes, including damage, done to the mattress. A good mattress should be able to go through our durability tests without a large change in firmness or significant loss of height.

Find out in even more detail how we test cot mattresses.

View all Cot mattresses