Silentnight Safe Nights Lullaby Cot Mattress review: firm, breathable and built for safer sleep

Our verdict

If you're looking for a cot mattress that prioritises safety, support and practicality over flashy extras, the Silentnight Safe Nights Lullaby Cot Mattress is worth considering.

Parent tester Izzy used the mattress every night with her daughter from 3.5 to 4.5 months old, including during the dreaded four-month sleep regression, and found it performed exactly as she hoped. The mattress felt supportive, fitted securely in her cot bed and gave her confidence thanks to its firm construction and strong safety credentials.

One of the first things Izzy noticed was the quality. She says the mattress "looks and feels premium" and was impressed by the snug fit in her daughter's cot bed, explaining that "it was reassuring that we couldn't see any gaps between the mattress and cot bed where our baby would be sleeping."

The breathable, hypoallergenic design was another highlight. Testing coincided with one of the first warm spells of the year and Izzy felt the mattress helped her daughter stay comfortable overnight, while the removable machine-washable cover made everyday maintenance straightforward.

There are a couple of drawbacks. Unlike some rivals, including waterproof models at a similar price point, the Silentnight Safe Nights Cot Mattress isn't water resistant, meaning you'll likely want to budget for a separate mattress protector. Izzy also found the secure fit made sheet changes slightly awkward when the mattress was inside a cot with raised sides.

That said, these are relatively minor complaints. Overall, Izzy felt the Silentnight Safe Nights Cot Mattress offered a good combination of comfort, safety and durability, adding that she would "confidently recommend it to other parents looking for a durable and safe cot mattress."

This foam-free cot mattress combines a firm, supportive feel with a removable machine-washable cover.

How we tested the Silentnight Safe Nights Cot Mattress

Izzy used the Silentnight Safe Nights Cot Mattress every night for five weeks with her daughter, who was 3.5 months old at the start of testing and 4.5 months old by the end.

The mattress was used in an everyday family setting, fitted inside an Ickle Bubba Snowdon cot bed and put through the realities of life with a young baby. During the testing period, Izzy's daughter had plenty of disrupted nights and as a result, Izzy made repeated trips back and forth to the cot.

As she puts it, “We really put the mattress through its paces with multiple pick up and put downs each night!” Alongside assessing comfort and support, Izzy also looked at how it performed in day-to-day use, including fit and breathability to get a realistic sense of how it would accommodate her daughter’s sleep routine.

During testing, Izzy scored the Silentnight Safe Nights Cot Mattress across key criteria including performance, quality and durability, ease of use and value for money, along with safety-focused areas such as firmness, comfort, cleaning and fit and compatibility  giving it strong overall scores, particularly for safety, firmness and durability where it performed especially well.

The Safe Nights range includes coordinating bedding and accessories, sold separately.

What does the Silentnight Safe Nights Cot Mattress come with?

The Silentnight Safe Nights Cot Mattress arrives ready to use and includes a removable quilted cover, which Izzy particularly liked for its soft feel and practical design.

Included in the box:

• Silentnight Safe Nights Lullaby Cot Mattress

• Removable quilted mattress cover

While the mattress itself doesn't come with any additional bedding or accessories, Silentnight offers a range of matching products that can be purchased separately, including:

• Mattress protector

• Fitted sheets

• Anti-allergy pillow (for older children)

• Safe Nights cot bed duvet set

Izzy appreciated the simplicity of the package and felt the quilted cover gave the mattress a more premium feel straight away.

What are the key features of the Silentnight Safe Nights Cot Mattress?

Izzy was particularly impressed by how securely this mattress fitted inside her daughter’s cot bed (the family are using the Ickle Bubba Snowdon Cot Bed) and how supportive it felt compared to the mattress she’d been using previously. As she explains, "This mattress is very firm and feels perfectly supportive for my daughter. It felt firmer than the mattress that we had been using previously."

Other notable features include a breathable polyester core, hypoallergenic materials and a foam-free design. Silentnight also backs the mattress with a five-year guarantee, which is useful given that many parents will use a cot bed mattress for several years as their child grows.

During the five-week testing period, Izzy was also pleased with how durable the mattress was. She says, "… It’s firmness holds well and we didn't see any loss of shape during testing."

The mattress arrived flat-packed in protective plastic packaging

How did the mattress arrive?

The Silentnight Safe Nights Cot Mattress arrived flat-packed in protective plastic packaging, so there was no waiting around for it to expand before use. Izzy found the setup process refreshingly simple. As she explains, "Because the mattress arrived flat, it just needed unpacking and some time to air out (we left it for three hours), before setting it up in the cot bed and using it for the first time."

Although Silentnight recommends allowing the mattress to air before use, Izzy didn't notice any strong odours when it was first unwrapped. She says, "From what we could see, it didn’t need any time to expand – just some time to air out slightly before first use, although we didn't notice any sort of smell."

Overall, it was a straightforward process from delivery to first use, with no assembly required beyond placing the mattress into the cot bed and fitting a sheet.

How does it look and feel?

Izzy's first impression was that the Silentnight Safe Nights Cot Mattress felt like a high-quality product. She particularly liked the quilted cover, which features a subtle cloud pattern and gives the mattress a softer, cosier look than some of the more basic cot mattresses she’d seen.

The cover feels soft to the touch and can be removed for machine washing, which is always useful with a young baby. As Izzy explains, "One night during testing we ran out of clean sheets, and we felt comfortable putting our daughter to sleep in her sleeping bag, straight on top of the mattress cover." That small moment reassured her that the materials felt comfortable and well finished. Overall, the mattress feels sturdy and well-made and it gives the impression that it's built to withstand everyday family life.

How comfortable is the Silentnight Safe Nights Cot Mattress?

Very. Rather than being overly soft, the mattress has a reassuringly sturdy feel while still providing a comfortable sleep surface for a growing child. During testing, Izzy's daughter moved onto the mattress without any obvious adjustment period and continued sleeping as she normally would.

As Izzy explains, "Our daughter seemed to adapt to the new mattress straight away, and we didn't observe any negative changes in her sleep which could have been caused by the mattress."

While it's impossible to know exactly how comfortable a child finds a mattress, Izzy felt the Silentnight Safe Nights cot mattress offered the right combination of support and comfort for everyday sleep.

The 140 x 70cm cot bed mattress fitted securely in our test cot bed, with no noticeable gaps around the edges.

How well does the mattress fit a cot?

A good fit is one of the most important things to look for in a cot mattress, and Izzy was pleased with how securely the Silentnight Safe Nights cot mattress sat inside the Ickle Bubba Snowdon Cot Bed. She found that it fitted snugly, with no noticeable gaps around the edges. As she explains, "It was reassuring that we couldn't see any gaps between the mattress and cot bed where our baby would be sleeping."

Because Izzy chose the cot bed version, which is slightly bigger than the cot version, she's expecting to get several years of use from it. She says, "We intend to use this product until our daughter outgrows the bed, making the mattress feel like a longer-term purchase rather than something that will need replacing after the first year.”

How practical is the Silentnight Safe Nights Cot Mattress for everyday use?

It’s very secure in the cot bed, which gives reassurance, but does make it a little fiddly when changing sheets. Izzy explains: “It fit our cot bed so securely that it was slightly tricky to lift out when we needed to change the sheet.”

In day-to-day use, this snug fit felt reassuring rather than problematic, although it did mean a bit more effort when lifting the mattress out for cleaning. She felt this would likely become easier once their Ickle Bubba Snowdon Cot Bed is converted into a toddler bed with open sides, making it easier to grip and move the mattress.

What safety features does the mattress have?

Safety was one of the strongest points for Izzy, particularly the firm feel and materials used. She says: “It’s foam-free and chemical-free, which gave us peace of mind straight away.”

The mattress is also fire retardant, hypoallergenic and tested to high UK safety standards in Silentnight’s SATRA-approved testing lab, including flammability checks. Overall, it gave her confidence that it was designed with safe sleep as the priority.

How breathable is the Silentnight Safe Nights Cot Mattress?

Testing took place during a warm spell, which helped put breathability to the test. Izzy explains: “Even during warmer nights, she didn’t seem uncomfortable or overly warm, which we were pleasantly surprised by.”

Part of this comes down to the mattress construction, which uses a breathable polyester core and a soft-touch quilted cover designed to allow airflow while still feeling cosy. The cover also has a cloud-pattern finish and is machine washable, which adds to the practical feel of the design. While not something she could measure scientifically, in real use it seemed to help maintain a comfortable sleeping temperature and avoid overheating.

The quilted cover unzips easily and can be machine washed when little accidents happen.

Is it easy to clean?

While Izzy didn’t clean the mattress itself, the removable quilted cover made cleaning straightforward. Izzy says: “The cover is easy to zip off and wash, which was really helpful with a young baby and inevitable little accidents.”

Minor leaks during testing didn’t reach the mattress core, so most cleaning was limited to the cover. As the mattress itself isn’t waterproof, Izzy felt a separate protector would be a sensible extra for longer-term use.

Is the Silentnight Safe Nights Cot Mattress good value for money?

Yes. While there are cheaper cot mattresses available, including budget options like the KATY cot bed mattress at around £60 for the same 140 x 70cm size, we felt the Silentnight justifies its higher price point when you take safety testing, materials and build quality into account.

At around £140, it sits firmly in the mid-range, but the firm, supportive feel, hypoallergenic materials and UK safety testing standards gave us added reassurance that it’s built for consistent, long-term use through the cot bed stage.

While the KATY sits at a significantly lower price point and is often chosen as a straightforward, no-frills option, the Silentnight positions itself more as a safety-led, structured sleep solution with stronger testing credentials and a more premium finish.

About the author

Tammy Jacks has over 20 years of experience in the publishing industry, holding key roles such as Managing Editor and Health & Beauty Editor for Woman & Home magazine in South Africa, and Assistant Editor for Living and Loving - a parenting title focused on children’s health and development.

She has contributed to a wide range of lifestyle publications (including magazines, journals and newspapers) and has edited books for fitness influencers and health professionals. As a researcher and writer, Tammy specialises in children’s development, wellbeing and safety. Over the years, she has reviewed countless toys and developmental aids, as well as essential baby products for everyday family life, from baby monitors and sleep aids to feeding equipment like highchairs and nursery must-haves, alongside baby travel gear such as baby carriers, child bike seats and lightweight strollers.

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