Firmness
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.
If you're shopping for a child or teenager, the case here is straightforward. The Miracoil® spring system offers zoned support, which Silentnight states is scientifically proven to improve spinal alignment and posture, useful during the years when both are still developing. The EcoComfort Fibres™ layer is breathable and helps maintain a comfortable temperature, handy if your child tends to run warm at night. It's hypoallergenic and free from foam and FR chemical treatments, a genuine reassurance for parents who'd rather avoid those materials. Yes, the Medium/Firm feel may seem firm at first to a child used to something softer, but firmer support generally suits lighter bodies well. Delivery is quoted at 14 days.
Key Features & what's inside
- Sleep surface. A luxurious quilted sleep surface sits on top, which means the first thing your child feels is a soft, cushioned finish. It adds an extra touch of comfort above the firmer layers beneath.
- EcoComfort Fibres. Beneath the surface, breathable EcoComfort Fibres™ soothe and help maintain a comfortable temperature through the night. If your child is a warm sleeper, this is the layer doing the quiet work.
- Support system. At the base, Miracoil® springs provide zoned support, scientifically proven by Silentnight to improve spinal alignment and posture. In practice, that means the hips and shoulders are held in a healthier position as your child grows.
Layer details from silentnight.co.uk product page, September 2026.
Who's it NOT for?
It's only available in a UK Single, so it won't work for double beds or adult couples. Anyone wanting a soft, cradling feel may find the Medium/Firm rating a little unforgiving. And at 21cm deep, it's slimmer than some sleepers expect, less of an issue for children than adults.
Silentnight Healthy Growth Comet Eco Comfort Miracoil Mattress
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How firm is the Silentnight Healthy Growth Comet mattress?
Silentnight rates it as Medium/Firm. That's a supportive feel rather than a plush one, which generally suits children and lighter sleepers well, although anyone expecting a soft, sink-in surface may find it slightly firmer than they'd like.
Does the Silentnight Healthy Growth Comet come with a trial?
Yes. Silentnight offers a 60-night trial on this mattress, so you can return it if it doesn't suit your child. It also comes with a 5-year guarantee for longer-term peace of mind.
Is the Silentnight Healthy Growth Comet good for allergies?
It's listed as hypoallergenic, and it's free from foam and FR chemical treatments, which many parents prefer. If allergies are a concern, those certifications make it a reassuring option, though pairing it with a washable mattress protector is still sensible.
What sizes does the Silentnight Healthy Growth Comet come in?
It's available in a UK Single only, priced at £219. That fits its purpose as a children's mattress, but if you need a small double or larger you'll want to look elsewhere in Silentnight's range.
How long does delivery take for the Silentnight Healthy Growth Comet?
Silentnight quotes delivery within 14 days when ordering from its own site. Timings may differ if you buy through a retailer, so check at checkout.
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