Firmness
Type
Open Coil Spring
Depth (cm)
27
Number of Layers
3
Trial Period (nights)
Warranty (years)
5
Price Range
£299 to £519
Best Sleeping Position(s)
Certifications
Assessed from the specification published by MattressNextDay, captured September 2026, and from regular price comparison across our UK retail partners.
Choose this if you want firm-leaning support without a premium price. The twice-tempered springs are built to keep their resilience over time, which means the mattress should hold its shape rather than developing dips early on. The breathable damask cover helps air move through the sleep surface, useful if you tend to run warm. It comes in five sizes from UK Single to UK Super King. MattressNextDay, the retailer listing it, states a 5-year guarantee and free next day delivery to mainland UK, though some addresses may incur a small fee. Yes, the fillings are simple polyester fibre rather than natural materials, but that simplicity is a large part of why the price starts at £299.00.
Key Features & what's inside
- Damask Cover. A cover made from breathable Belgian damask fabric, which means air can move through the sleep surface rather than getting trapped against you. It gives a traditional, tailored finish.
- Soft White Fibres. Soft fibre fillings made from 100% polyester sit above the springs. They add a slightly softer initial feel before you reach the firmer support beneath.
- PostureTech CS Springs. These springs respond to your body weight to provide deep down support, so heavier areas like hips and shoulders get pushed back where needed. They are twice tempered, which means the steel is treated to stay resilient over time.
Layer details from mattressnextday.co.uk product page, September 2026.
Who's it NOT for?
If you like a soft, cradling surface or sleep mainly on your side with a lighter build, this medium firm feel may press a little too hard on shoulders and hips. It's also an open coil design, so couples who move at different times may notice more motion transfer than with pocket springs.
Sealy Ortho Plus Essential Mattress
Across owner reviews on MattressNextDay, customers report high satisfaction with comfort, supportive feel and material quality. Some note it feels firmer than expected, which suits spinal support but may not please softness lovers.
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How firm is the Sealy Ortho Plus Essential mattress?
It's listed as medium firm. Some owners report it feels firmer than expected, so treat it as sitting at the firmer end of medium firm. That's helpful for back sleepers wanting spinal support, but lighter side sleepers may find it a little unforgiving.
What springs does the Sealy Ortho Plus Essential use?
It uses Sealy's PostureTech CS springs, an open coil system made from high tensile steel. The retailer page describes the same system as both 'Open Coil Springs' and 'PostureTech CS Springs'. The springs respond to your body weight for deep down support and are twice tempered for durability.
How deep is the Sealy Ortho Plus Essential mattress?
It's 27cm deep, a fairly standard depth that most fitted sheets will cover comfortably.
Does the Sealy Ortho Plus Essential come with a guarantee?
MattressNextDay, the retailer listing this mattress, states a 5-year guarantee. As that's stated on a retailer page rather than Sealy's own site, check the terms at your point of purchase before buying.
What sizes does the Sealy Ortho Plus Essential come in?
Five UK sizes: Single, Small Double, Double, King and Super King, priced from £299.00 up to £519 depending on the size you choose.
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