These are the best cot mattresses that helped our parent testers and their baby get a good night’s sleep

Best cot mattress

by Stephanie Spencer |

You've already bought the best cot or crib for your baby to safely sleep in, so now it’s time to find the very best cot mattress for your baby. We know how important sleep is for babies, and the best way to encourage sleep is by creating a sleep environment that's cosy and safe for your baby. The right baby and toddler mattresses can do just that.

Safety is paramount when you're a parent and as well as comfort, this should be at the forefront of your mind when choosing the best cot mattress for your baby or cot bed mattress for your toddler. That can include making sure it's the right size for your cot, crib or cot bed so there are no gaps around the edges. Many of the mattresses on our list can be ordered in different sizes so be sure to check the sizing carefully as there is a slight difference in size between cot mattresses and cot bed mattresses.

Along with safety, there are a few other features you'll want to consider. You may be looking for your child's cot mattress to be made of a certain material, especially if they suffer from allergies. It's also likely that you'll be after a cot mattress that can be either washed or comes with a removable, washable cover. While this can all feel like a lot to consider, we've done the hard work for you and rounded up our top thirteen choices.

Selecting a mattress for your baby is a hugely important task and actually very personal. Whether you're selecting a mattress for a bedside crib or you're moving your toddler into their own room for the first time, you want to find the best mattress to suit your little one's needs.

Remember, if you are planning to use a bedside crib for your newborn to sleep in, you would need a different-size mattress for this. Similarly, if you plan to use a travel cot in the future, this will usually come with its own mattress.

The best cot mattress at a glance:

Best overall cot mattress: CuddleCo Lullaby Hypo-Allergenic Bamboo Cot Bed Mattress - Buy now on Amazon UK
Best premium mattress: Simba Baby Cot Bed Mattress - Buy now on SIMBA
Best budget cot mattress: Tutti Bambini Sprung Cot Bed Mattress - Buy now on Amazon UK
Best long-lasting cot mattress: The Little Green Sheep Natural Twist Cot Bed Mattress - Buy now on Amazon UK

How we tested and chose these mattresses

Our Mother&Baby Awards are renowned in the industry for being one of the most highly respected product awards for baby and parenting products and every year, we arrange for thousands of independent mum reviewers to test the latest products on the market. Find out more about how we test and what considerations we take into account in our testing process.

Our independent mums review products based on their usability, design, quality, and value for money. Reviewers give us qualitative feedback on their experience with the product, which our team of journalists review to decide our recommended products. We combine this with mattresses that have been tried and loved by parents, reading hundreds of online reviews so you don't have to.

From all this work, the best cot mattresses are chosen and listed below, along with the review comments that we thought would be most useful to those looking for the best cot and cot bed mattresses.

Our editorial team is also constantly updating our best of articles and looking for new cot and cot bed mattresses to test so that we can help you find the best – be that a cheaper product that we want to test for value for money or the latest innovation.

Our sleep expert's advice on choosing a mattress

In addition to this testing and reviewing, we spoke to sleep expert, Emily McInnes from Sound Asleep Coaching who offered advice on what you should look for when choosing a mattress and how to create a safe sleep environment for your little one. This includes:

  • A firm, flat mattress

  • No rips or tears in the fabric

  • Waterproof cover

  • Fire resistant

  • Breathable

  • Adhere to the British Safety Standards (BSI)

The best cot mattress 2024

Best overall cot mattress

The CuddleCo Lullaby hypo-allergenic bamboo cot bed mattress is a two-time Mother&Baby Awards Gold winner, featuring two sides: one soft side for cosy nights and another waterproof mattress cover layer included for easy potty training. Crafted with natural hypo-allergenic and anti-microbial properties, it creates a germ-free sleep environment, ensuring peace of mind for mums. Our mum tester Steph loved how her son took to this mattress."My son has really taken to this mattress and it's given him plenty of good nights' sleep! I feel I can put him down easier and feel more at ease knowing he's on a comfortable mattress for the night.” 

Measuring 140cm x 70cm, parent testers also loved its quality and how perfectly it fit their child’s cot beds as well as how much space it allowed for little ones to rest and grow. Mum Erin particularly loved the fit, commenting, “it fits the cot well and doesn’t have gaps around the top or bottom.”

Parents also found their tot remained comfortable all night long with this cot bed mattress, with our mum tester vicky saying how cool it kept her son. “His mattress has never felt too warm or sweaty even in 30 degree plus temperatures." She said. Parents also loved its reversible and washable cover, making maintenance a breeze.

The CuddleCo Lullaby Hypo-Allergenic Bamboo Cot Bed Mattress was awarded Gold for Best Sleep Product at the Mother&Baby Awards 2024 and 2023.

Read our full CuddleCo Lullaby Hypo-Allergenic Bamboo Cot Bed Mattress review.


  • Breathable airflow fibres to maintain baby's temperature
  • Anti-allergy, so great for tots with allergies
  • Removable cover which makes washing easy


  • Spare cover not included so would need to dry quickly if washed
Size:140 x 70cm
Material:Bamboo fabric
Machine washable cover:Yes
  • Includes a machine washable cover
  • Made from natural fibres
  • Reversible training layer

Best long-lasting cot mattress

A firm favourite amongst mums and dads, The Little Green Sheep Natural Twist Cot Bed Mattress is crafted with four natural ingredients - Coconut Coir, Natural Latex, Wool, and Cotton - this mattress offers 100% natural comfort, free from harmful chemicals, ensuring the right support for your little one from infancy to toddlerhood.

The firm side is recommended for babies up to 12 months to provide a safe and supportive sleep surface, while the more supple side features natural latex for more cushiony comfort as your child grows. Our mum tester Susan loved the fact it was made using natural fibres, giving her peace of mind. “Knowing that the mattress is hand made from four natural breathable materials with no harmful chemicals or toxins gives me peace of mind. The materials are also temperature regulating which ensures the baby does not get too hot” she said.  

As well as its natural materials, mum testers also found this a very comfortable and high quality mattress, with mum tester Jamie loving the ‘try before you buy’ feature. “The mattress itself was weighty but not too heavy to pick up and move around. I also liked that the plastic cover provided a 'try before you commit' - it allowed me to double check that the mattress would fit my cot bed frame correctly and if not I would be able to return the mattress provided I did not remove the cover” she commented. 

The main area where our mum tester Lucy thought this could be improved is in the addition of a waterproof cover. “Being made of natural materials the product information states that it is therefore very important to avoid spills or accidents getting through to the mattress and that a waterproof mattress protector should therefore be used" she said.

Won Gold at the Mother&Baby Awards 2021 for Baby Sleep Product.

Read our full The Little Green Sheep Group Twist Natural Cot Bed Mattress review.


  • Dual-sided with a firmer side for babies and a softer side for 12 months+
  • Breathable materials to maintain baby's temperature
  • Non-toxic to offer peace of mind to parents who prefer a more natural approach


  • No waterproof covers included so would need to be bought separately
Size:140 x 70cm
Material:Hypo-allergenic wool
Machine washable cover:No
  • Dual-sided
  • 100 per cent cotton
  • Hypoallergenic and temperature regulating

Best budget cot mattress

Made using foam and open coil springs, this affordable yet high-quality mattress supports your baby's natural posture while ensuring breathability with hypoallergenic properties for a peaceful night's sleep.

The mattress comes with a removable washable cover, making it easy to clean in case of any accidents, and is quilted with 100% polyester filling along with the fully breathable Just-Tec fabric which enhances airflow,  to help keep your little one cool and comfortable throughout the night, while the hypoallergenic properties provide added peace of mind for parents. One parent tester found their little one remained very comfortable on this mattress, commenting; “We bought this when we moved our daughter from a cot to toddler bed and she has slept soundly every night since (about 3 weeks ago). That's really all the proof I need as she has been quite a fussy sleeper and would not sleep if she was not comfortable!”


  • Affordable option
  • Hypoallergenic, so good for babies and toddlers with allergies
  • Supportive coil springs


  • Some parents found it a little too soft for their newborn so might be better for toddlers
Size:120 x 60
Machine washable cover:Yes
  • Open coil spring
  • Hypoallergenic
  • Removable wash cover
  • Fully breathable Just-Tec fabric

Best cot mattress with Clevafoam technology

Designed to provide optimal support for your baby's developing head and joints, the ClevaMama Clevafoam Support Cot Mattress is made using ClevaFoam®, offering superior protection against Flat Head Syndrome, scientifically proven to reduce pressure on the head by 50% and increase support by 80%.

The mattress is breathable and lightweight with reduced heat retention, creating a comfortable sleeping environment for your little one. Its hypoallergenic and pH-balanced properties make it suitable for babies with sensitive skin or allergies. 

The removable and machine-washable cover with a reverse zip ensures easy cleaning, while the mattress is tested for harmful substances according to global criteria, meeting OEKO-TEX® STANDARD 100 standards. This mattress offers a three-year guarantee, providing long-lasting comfort and safety for your baby.

Our mum tester Melissa found her baby settled well when transitioning to this mattress. “Since using the Clevafoam mattress my baby has slept much better which makes mum life much more manageable after a full night's sleep. My baby settles quickly and seems less restless in the hot weather than he did with his previous mattress” Melissa said. Its compact delivery box makes it convenient for parents with limited space. 

The main change our parent testers would have liked to see is the addition of a waterproof fabric or cover. Mum tester Melissa commented, “my baby has reflux so is sick quite often. I did purchase a waterproof sheet however, though it took a small part of the comfort away with the sheet being thicker than a normal sheet.”

Won Silver at the Mother&Baby Awards 2022 for Best Bedding.

Read our full ClevaFoam Support Baby Mattress review.


  • Hypoallergenic
  • Made with ClevaFoam technology to provide support for developing joints
  • May prevent Flathead syndrome
  • Removable washable cover for easy cleaning of spills and accidents


  • One tester felt it wasn't waterproof enough so bought a separate cover
Size:140 x 70cm
Machine washable cover:Yes
  • Breatheable material
  • Hypoallergenic
  • Pressure relief support

Best cot mattress for support

Made using a natural lambswool support system to ensure optimal support for your baby's head and body during those crucial early years, the Silentnight Safe Nights Superior Pocket Cot Mattress is designed with a breathable mesh cover to promote airflow for a more hygienic sleeping environment, while the Purotex treatment combats moisture, mites, and allergens. 

Our real parent testers found this mattress helped their little ones to settle quickly and sleep soundly, with our mum tester Terri commenting, “It could be a coincidence, but my normally bad sleeping toddler has started sleeping through the night since using this mattress!” Its compact and lightweight design makes it convenient for travel, and the removable and washable cover ensures easy cleaning after accidents.

One thing our mum testers found could have been more helpful were the care instructions, and mum tester Danielle would have liked it to be waterproof or come with a waterproof cover for simplified cleaning.

Read our full Silentnight Safe Nights Superior Pocket Cot Bed Mattress review.


  • Hypoallergenic for asthma and allergy sufferers
  • Mini-pocket core for responsive support
  • Breathable mesh cover for better airflow


  • Would benefit from buying a waterproof cover
Size:140 x 70cm
Material:Features a mini-pocket core combined with lambswool and clever 3D mesh cover
Machine washable cover:Yes
  • Waterproof panel
  • Washable cover
  • Hypoallergenic
  • Double-sided

Best dual-sided cot mattress

With a dual-sided design and a pocket-sprung core, the SnüzSurface Duo Cot Mattress offers support as your little one transitions into toddlerhood. Simply use the firmer side for babies and change to accommodate their changing needs as they grow.

Designed to withstand leaks, accidents, and spills, this mattress boasts a waterproof surface, ensuring easy cleanup and maintaining a hygienic sleeping environment. The innovative 3D breathable mesh cover helps keep little ones cool in the night, while the anti-dust mite barrier provides added protection.

Suitable from birth to 4 years and compliant with safety standards, it offers longevity as well as peace of mind to parents. The removable, machine-washable cover simplifies maintenance, while the 2-year guarantee ensures its durability.

Real parent testers loved the impact it had on their child's sleep quality, although some did struggle to find a mattress cover to fit properly, with mum tester Ellie saying, “Excellent quality mattress. Breathable, firm but comfortable seeming. The only issue is, you absolutely cannot get sheets to fit this mattress unless they’re directly bought from Snuz themselves.” It was also annoying that the mattress needed to rest flat for 7 days upon opening before use.


  • Dual-sided with a firmer side for babies and a softer side for 12 months+
  • Waterproof
  • Breathable mesh cover


  • Takes up to a week to decompress
Size:140 x 70cm
Machine washable cover:Yes
  • Pocket spring core
  • Hypoallergenic
  • Waterproof cover

Best fully washable cot mattress

Designed with a unique hollow core and fully breathable mesh, the Purflo Cot Bed Mattress ensures optimal air circulation, providing a comfortable and safe sleep surface for your baby or child. Its suitable from birth to 4 years (or up to 25kg), conforming to your baby's body, helping prevent flat head syndrome and promoting healthy sleep patterns.

Certified as fully air-permeable, the Purflo mattress maintains a thermo-neutral environment, helping regulate your baby's temperature for a comfortable sleep experience year-round, even on those hot summer nights. Its removable and washable cover ensures optimum hygiene, preventing the build-up of dust mites and allergens while also extending its lifespan for future use.

Hypoallergenic and featuring specialist fibre padding that is chemical and allergen-free, this is an ideal mattress for babies prone to allergies, asthma, or eczema. Real mum tester Jen loved how breathable this mattress was as well as the convenient washable design, commenting, “fully breathable so if little one decides to roll over I know they will be safe. Washable! Oh my days, a washable mattress, so very very handy for those little accidents!” As mum Jen says, unlike traditional foam mattresses, the Purflo mattress can be washed repeatedly, keeping it fresh and pristine for years to come.


  • Fully washable
  • Thermo-neutral
  • Conforms to the baby’s body


  • Mesh may get frayed over time
Size:140 x 70cm
Material:85% Polyester 10% Cotton 4% Amicor Pure™ 1% Polypropylene
Machine washable cover:Yes
  • Certified as fully air-permeable
  • Hypoallergenic: Amicor Pure fibre padding that reduces dust mite build-up
  • Thermo-neutral, so that it maintains room temperature so baby doesn’t get too hot or too cold

Best bamboo pocket-sprung cot mattress

Offering both luxury and practicality, the CuddleCo Signature Children's Mattress is made from bamboo, a hypoallergenic surface. This mattress also responds to your child's body position, offering them comfort and support as they grow.

Our real mum testers loved the double-sided design, with a soft bamboo fabric side for infants and a waterproof training layer for older children making it nice and easy to clean during potty training and everyday use. Mum tester Hayley said, “my little girl finds the fabric side very comfortable and she sleeps really well on it.”

Hypoallergenic and breathable, it provides a hygienic and comfortable sleep environment for your little one, with our mum testers finding it helped settle their babies quickly, even little ones with sensitive skin. “I love the hygienic aspect - the mattress is anti-allergenic and anti-microbial. It's breathable, meaning the mattress stays safer, and fresher for my baby”, commented our mum tester Laura. 

Although some mums had a personal preference for a sprung mattress for added support, overall, they couldn’t find much they’d change with this mattress. Made here in the UK, parents loved the comfort and durability of this mattress, also appreciating its reasonable price point.

Read our full CuddleCo Comfi-Love Signature review.


  • Waterproof side for when potty training
  • Breathable to maintain baby and toddler's temperature
  • Pocket sprung


  • Some parents felt it was too firm
Size:140 x 70
Material:Bamboo fibres
Machine washable cover:Yes
  • Pocket sprung
  • Hypoallergenic
  • Waterproof

Best cot mattress for adaptive comfort

The CuddleCo Signature hypo-allergenic bamboo pocket sprung cot bed mattress is made using bamboo fabric which boasts natural hypoallergenic and antimicrobial properties, promoting a cleaner and germ-free environment for your little one. Dual-sided, it’s designed to adapt to your child's needs as they grow, featuring a luxurious bamboo fabric on one side and a waterproof training layer on the other. 

Mum testers loved the comfort and support it offered their little ones, with our mum tester April sharing how her daughter loved this mattress. “This mattress seems really comfy, it’s really soft and springy and easy to clean. My daughter really liked it, it felt like it contoured to her shape and she looked so cosy when she was sleeping.” 

Mum and dad testers liked its compatibility with cot sizes and easy-clean properties, adding to its convenience. The only thing some parents worried about was that it was a bit too soft for babies under six months, with mum tester Alexandra saying, “ I felt confident leaving my little one on it during her day time naps (when they happen that is!) but before six months old I would worry the mattress is a tad soft."

Won Bronze at the Mother&Baby Awards 2023 for Baby Sleep Product.

Read our full CuddleCo Signature hypo-allergenic bamboo pocket sprung cot bed mattress review.


  • Bamboo fabric has anti-microbial properties
  • Double-sided with a waterproof side for potty training when they're older


  • Doesn't come with a spare cover
Size:140 x 70cm
Material:Bamboo fabric
Machine washable cover:<meta charset="utf-8">Yes - easy clean waterproof training layer
  • Double-sided, with easy to clean training layer
  • Hypoallergenic
  • Pocket-sprung

Best organic cot mattress

If you’re looking for a sustainable and organic mattress, then the Naturalmat Quilted mattress might be just what you’re looking for. Made using organic materials, including coir, lambswool, and latex foam, it provides excellent breathability and softness while being hypoallergenic and anti-dust mite. 
Our mum tester Emma found it very comfortable for her son, commenting, “my son Olly had a great night’s sleep on this. It’s a moderately soft mattress which is really comfortable.”

The chemical-free composition make this mattress a safe choice for your child and also offers added support. Parents also loved how durable it is, and liked the peace of mind the five-year guarantee gave them. It's designed to last until your child outgrows it, making it excellent value for money. 

Read our full Naturalmat Quilted Latex Mattress review.


  • Hypoallergenic and natural materials
  • Designed to grow with baby


  • Additional charge for mattress cover
Size:Made to measure
Material:Natural and organic
Machine washable cover: Optional
  • Made to measure
  • Breathable fabric
  • Medium support

Best cot mattress with 100 per cent allergy protection

This mattress is all about giving your baby a cleaner, fresher, and healthier sleep environment. Featuring a blend of nature's finest TENCEL™ fibres and Purotex® anti-allergy protection, The Mother&Baby Gold Collection baby and toddler mattresses ensure a hygienic sleep space. This feature gave our mum tester Louise some much-needed peace of mind, with her commenting, “We have a cat in our house, so I love the idea that this mattress can clean cat allergens! With the usual new baby anxieties, I’m so keen on making sure my little one’s environment is as natural and clean as possible.”

The Purotex technology found in this White Gold Anti-allergy Pocket Sprung Mattress is proven to reduce house dust mite allergens by 93.7%, cat hair allergens by 92.8%, and dog hair allergens by 66.7%. The inclusion of Tencel natural fibres enhances breathability and temperature control for added comfort. One dad found it really helped his daughter to get back off to sleep after feeding. “We bought this as we were worried or 6-month-old was waking due to not being as comfortable as she could be. Now she sleeps right through most nights and straight back to sleep when she does wake for a night feed" he said. 

This mattress features individual adaptable pocket springs for tailored support for your little one, is suitable for cots, and comes with a waterproof membrane. You’ll be pleased to know all covers are removable and washable, ensuring easy maintenance and long-lasting freshness.


  • Natural coconut coir for firmer sleep
  • Eliminates allergens
  • Enhanced moisture management
  • Removable and washable covers for easy cleaning
Size:120 x 60cm
Material:Polyester with coconut coir
Machine washable cover:Yes
  • Dual-sided
  • Pocket sprung
  • Eliminates allergens

Best cot mattress for four sleeping options

Suitable from birth, this hypoallergenic mattress from Obaby is designed to support your baby's muscle development and bone growth, thanks to its firm yet resilient design. Made with coconut coir bonded with natural latex, it offers a naturally bouncy and soft feel, promoting a comfortable sleep environment for your little one. Parents loved the level of comfort this mattress gave their babies, with one mum tester commenting, “although there are pocket springs in it the mattress is also surrounded by foam so it seems nice and comfy but has that spring and bounce you get with pocket springs to give our daughter that support.” 

As your baby grows, this mattress adapts to their body with a reversible design. One side features individual pocket springs encased in high-grade, dent-resistant nursery foam, offering increased support for your tot's back, neck, and head, aiding their posture and helping them drift off in the process. The other side has a Tencel fabric top panel, helping keep them cool in the night, while the polyurethane panel underneath provides waterproof protection against little accidents. Parents found this mattress to be great at keeping their little ones cool, one parent tester commented, “If she naps on my bed, her whole back is wet, but on this matress-never.” 

This mattress is also very easy to keep clean with its removable and washable covers, including a water-resistant inner cover that can be used as a sleeping surface while the outer cover is being cleaned. Available in two different sizes to fit Obaby's range of cots, cot beds, and mini cot beds, this dual-core mattress is a reliable choice for parents.


  • Absorbent and supportive for babies
  • Water-resistant
  • Mattress cover unzips in order to flip core from baby side to toddler side


  • Some parents found it had quite an unpleasant odour at first

Best premium mattress

Designed to provide your little one with the perfect balance of comfort and support from birth to toddlerhood, this double-sided Simba Hybrid Cot Bed Mattress is made using Simba’s award-winning technology with eight layers of engineered comfort, ensuring your child gets the quality sleep they need each night.

On one side, a firm, flat surface provides optimal support for newborns, keeping them safe from bacteria, allergens, and chemicals. Then, at 12 months and beyond, simply flip it over for a cushioned, edge-to-edge support suitable for toddlers. This versatile design ensures your child's sleep needs are met as they grow, saving you money in the long run.

As well as loving the seamless transition between each side, our parent testers loved the convenience of the removable, washable cover, particularly if accidents happened. One mum tester said, “with it being a child’s mattress there are often times they need a thorough clean and the fact you can easily remove the cover to machine wash it is fab."

Although some parents were put off by the premium price, our parent testers found it really was worth the investment, with one of our mum testers finding her two-year old son loved this after being moved into his own room. “He has done amazingly well at settling into his own room and I do believe the mattress plays a big part in this. It is such a comfy mattress and perfect for little ones. My son used to regularly wake up but I’m beginning to question if maybe he just wasn’t as comfy on his previous mattress as he now sleeps so well.” She said.

The Simba Baby Cot Bed Mattress was awarded Bronze for Best Sleep Product at the Mother&Baby Awards 2024.

Read our full Simba Baby Cot Bed Mattress review.


  • Double-sided so grows with your baby, with one firmer side for babies and one for 12 months +
  • Washable cover for easy cleaning
  • Designed to last
  • Eight layers to create extra comfort


  • On the more expensive side so might not be within everyone's budgets
UK Single Mattress:90W x 190L (cm)
  • The Hybrid® Cot Bed Mattress has a double-sided design. We've added helpful Firmer/Softer labels to each side of the mattress so you'll always know which side is which
  • Soft, breathable, knitted outer. Breathable cover. Removable for machine washing.
  • Water-resistant inner lining. Breathable, fixed inner lining wraps round internal layers for durability and shape retention. 100% breathable.
  • Thick layer of firm Simba Renew. Breathable, firm comfort layer ensures the recommended flat, firm sleep surface for babies up to 12 months.
  • Responsive Aerocoil® spring layer. Innovative central spring layer provides responsive support for toddlers aged 1-3yrs; firmer springs provide edge-to-edge stability and roll-free security.
  • Medium layer of Simba Renem. Medium to firm comfort layer provides optimum core support for toddlers.
  • Cushioning layer of  Simba Renew. A more cushioned, comfort layer provides soft, cloud-like surface support.
  • Water-resistant inner lining Breathable, fixed inner lining wraps round internal layers for durability and shape retention. 100% breathable.
  • Soft, breathable knitted outer. Breathable, anti-allergenic cover. Removable for machine washing.

Cot mattress – All you need to know

Types of cot mattress

When it comes to choosing a mattress for your baby's cot, you have three main choices:

Foam cot mattresses: They are designed to provide the right support and maintain your baby's natural posture.

Spring or pocket-spring cot mattress: With coiled spring interior with layers of felt and foam padding. A spring inner core will support your baby and hold its shape well.

Coir or natural fibre cot mattress: With a core of coconut fibre, they tend to be more breathable and naturally hypoallergenic.

Hollow frame (PurFlo) cot mattress: Made only by brand PurFlo, this mattress is supposedly the only fully breathable and fully washable mattress.

Choosing the right cot mattress for you and your child


According to the Lullaby Trust, it’s best to choose a firm and flat mattress. It'll need to fit your baby's cot snugly and there should be no gaps for fingers or toes to get trapped. Keep an eye out for the British Standards with the prefix BSI number BSEN716 on swing tickets and product specifications, as this is the standard for cots, prams and mattresses.

It's important to avoid adding any extra bedding in the cot, such as duvets, as they can increase the risk of SIDS. If it’s cold, it's recommended you opt for a baby sleeping bag instead of extra blankets or covers. You can introduce a duvet when your little one gets older.

Emily McInnes from Sound Asleep Coaching recommends that "the optimal bedroom temperature for safe, comfortable sleep is 16-20'C” and that "it is safer for your baby to be slightly on the cooler side than warmer side." For that reason, she notes that "if your baby is in a sleeping bag, ensure that they are wearing the correct tog based on the temperature of the room."


You'll want a cot mattress that is protected by a waterproof cover. This will help keep the mattress clean and dry, as the cover can be wiped down.

Can I use a second-hand mattress?

Generally, it is advised that babies should sleep on a new mattress as The Lullaby Trust suggests there is some evidence to suggest that bringing in a mattress from another home might increase the risk of sudden infant death (SIDS) very slightly. While this link has not been proven, you might want to be cautious about using a second-hand cot mattress.

If you do want to use a second-hand cot mattress - perhaps given to you by a friend or family, or from your older child, The Lullaby Trust say "to make sure the mattress you choose was previously completely protected by a waterproof cover, with no rips or tears and is in good condition. The mattress should also still be firm and flat to keep your baby sleeping safely."

What size mattress do I need for a cot or cot bed?

Baby mattresses come in a variety of sizes, depending on what sort of bed your baby is sleeping in.

Moses basket mattress: normally 28cm x 75cm, but it depends on the brand of Moses basket

Travel cot mattress: 65cm x 95cm

Small cot mattress: 54cm x 90cm

Cot mattress: 60cm x 120cm

Cot bed mattress: 70cm x 140cm

Although it can differ depending on the type of mattress you buy, typically, a cot mattress will last between 3-5 years.

About the experts

Emily McInnes is a Paediatric Nurse and Certified Holistic Sleep Coach. She has over ten years experience in the healthcare setting and has a passion for supporting parents with their child's sleep. She has a vast amount of knowledge in paediatric sleep which she is passionate about sharing with the wider community to educate and reassure parents about the biologically normal sleep behaviours of babies and toddlers. Follow her at Sound Asleep Coaching.

Stephanie Anthony is the Deputy Digital Editor at Mother&Baby and auntie to four aged 7 to 2 months old. With a particular interest in health, she loves discovering products that make parent’s lives easier.

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