Firmness
Medium Firm
Type
Eco-Friendly Mattress
Depth (cm)
21
Number of Layers
3
Trial Period (nights)
60
Warranty (years)
5
Price Range
£219
Best Sleeping Position(s)
Certifications
Assessed from Silentnight's published specification for this mattress, captured September 2026, and from regular price comparison across our UK retail partners.
The strongest reason to choose this mattress is the combination of proper zoned support and a clean-sheet approach to materials. The Miracoil® spring system is scientifically proven to improve spinal alignment and posture, which matters during the years a child's back is still developing. The EcoComfort Fibres™ layer is breathable, so a warm sleeper should feel a little less clammy than on a dense foam alternative. Being foam free and FR chemical treatment free is rare at this price, and at £219 for a UK Single it sits at the affordable end without feeling flimsy. Add the 60-night trial and 5-year guarantee from Silentnight, and there's room to change your mind.
Key Features & what's inside
- Sleep surface. A luxurious quilted sleep surface that adds an extra touch of comfort. You'll feel a soft, gently cushioned finish rather than sleeping directly on the firmer layers below.
- EcoComfort Fibres. Breathable EcoComfort Fibres™ that allow air to move through the comfort layer. In practice this means cooler sleep, useful for children who tend to overheat at night.
- Support system. Miracoil® springs offering zoned support, scientifically proven to improve spinal alignment and posture. The zoning gives more resistance where body weight concentrates, keeping the spine in a healthier position.
Layer details from silentnight.co.uk product page, September 2026.
Who's it NOT for?
It's only made in a UK Single, so it won't work for couples or anyone wanting a double upwards. The medium/firm feel may be slightly too solid for very lightweight side sleepers, and at 21cm deep it will sit lower in the frame than a chunkier adult mattress. If you want memory foam contouring, this foam-free design isn't it.
Silentnight Healthy Growth Comet Eco Miracoil Mattress
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How firm is the Silentnight Healthy Growth Comet Eco mattress?
Silentnight describes it as medium/firm. That means a supportive, fairly solid feel with a quilted sleep surface softening the top, which suits most back and front sleepers, although lightweight side sleepers may find it a little too firm.
Does the Silentnight Comet Eco mattress contain foam?
No. It's built from EcoComfort Fibres™ over Miracoil® springs, with no foam and no FR chemical treatments. It's also hypoallergenic and naturally resistant to allergens, a sensible choice if your child has sensitivities.
What sizes does the Silentnight Healthy Growth Comet Eco come in?
It's available in a UK Single only, priced from £219. There's no double or king option, so it's aimed squarely at single beds, and its 21cm depth works well on children's frames and bunk beds.
Is there a trial period on the Silentnight Comet Eco?
Yes. Silentnight offers a 60-night trial on this mattress, alongside a 5-year guarantee, so you have time to see how your child settles on it before committing.
How long does delivery take for the Silentnight Comet Eco?
Silentnight lists delivery at 14 days for this mattress.
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