Firmness
Medium
Type
Pocket Spring
Depth (cm)
24
Number of Layers
3
Trial Period (nights)
60
Warranty (years)
5
Price Range
£229 to £255
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 main draw is the balance of support and breathability at a modest price. The 600 Mirapocket springs respond individually, which means the mattress adapts to a growing body rather than pushing back uniformly, and the zoned design targets spinal alignment. EcoComfort Fibres in the comfort layer help air move through, so warm sleepers should stay a little cooler through the night. There's no foam and no FR chemical treatment, a genuine plus for allergy-prone children, and the hypoallergenic build reinforces that. Yes, the price range of £229 to £255 is more than a basic children's mattress, but the pocket spring construction and 5-year guarantee justify the step up. Delivery is quoted at 14 days.
Key Features & what's inside
- Sleep surface. A breathable quilted sleep surface, which means a soft first point of contact that lets air circulate rather than trapping warmth.
- Support system. 600 Mirapocket springs providing zoned support, which Silentnight states is scientifically proven to improve spinal alignment and posture. Each spring moves independently, so support follows the body's shape.
- Comfort layer. Breathable EcoComfort Fibres designed for cooler sleep, helpful if your child tends to overheat at night.
Layer details from silentnight.co.uk product page, September 2026.
Who's it NOT for?
This is a children-focused design available only in UK Single and UK Small Double, so couples or anyone wanting a Double or larger should look elsewhere. If your child prefers a noticeably soft or firm feel, the medium tension may not suit. At 23.5cm deep, it's also slimmer than some adult mattresses.
Silentnight Healthy Growth Astro Eco 600 Pocket Mattress
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How firm is the Silentnight Healthy Growth Astro Eco 600?
It's a medium feel, according to Silentnight. That middle-ground tension suits most growing sleepers in most positions, although children who strongly prefer a very soft or very firm surface may find it a compromise.
Does the Silentnight Astro Eco 600 come with a trial?
Yes. Silentnight offers a 60-night trial, so you can return it if it doesn't suit, and the mattress carries a 5-year guarantee.
Is the Silentnight Astro Eco 600 good for allergies?
It's certified hypoallergenic and is free from foam and FR chemical treatments, which makes it a sensible pick for allergy-prone children or parents who prefer to avoid chemical fire retardants.
What sizes does the Silentnight Astro Eco 600 come in?
Two sizes: UK Single and UK Small Double. Pricing runs from £229 to £255 depending on size, and it's stocked by 2 retailers.
How deep is the Silentnight Astro Eco 600 mattress?
It measures 23.5cm deep. That's slightly shallower than many adult mattresses, but standard fitted sheets should still fit comfortably, and it's a sensible height for a child's bed frame or bunk.
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