Firmness
Medium Firm
Type
Memory Foam
Depth (cm)
27
Number of Layers
2
Trial Period (nights)
100
Warranty (years)
5
Price Range
£299 to £559
Best Sleeping Position(s)
Certifications
Assessed from the specification published by Mattress Online, captured September 2026, and from regular price comparison across our UK retail partners.
If you like memory foam's pressure relief but worry about feeling stuck or sleeping hot on solid foam, the spring core here is the appeal: the MemorySense layer cushions your shoulders and hips while the PostureTech springs keep your spine supported and let air move through the mattress. The medium to firm feel suits back and stomach sleepers well, although lightweight side sleepers may find it slightly too firm. It's a simple two-layer build, but that simplicity keeps the price honest, from £299 for a single. Buying through Mattress Online adds free delivery to most UK locations with a two-hour time slot, and a 100-night trial if you buy a mattress protector with it.
Key Features & what's inside
- Comfort Layer. A layer of MemorySense memory foam sits on top, which means it moulds to your body shape and eases pressure on your shoulders and hips. It gives you that gentle cradling feel memory foam is known for.
- Support System. Beneath the foam, PostureTech Core Support Springs do the structural work, keeping your spine aligned and adding responsiveness so you don't feel stuck when changing position. The springs also allow more airflow than a solid foam base.
Layer details from mattressonline.co.uk product page, September 2026.
Who's it NOT for?
If you share a bed and are easily disturbed, springs can transmit a little more movement than all-foam designs, and one owner review mentioned motion transfer. Those wanting a genuinely firm, orthopaedic-style feel should look elsewhere too, as some owners found it softer than expected. And if you dislike memory foam's hug, this isn't for you.
Sealy Advantage Memory Essential Mattress
Across 412 verified owner reviews on the Mattress Online product page, rated 4.7 overall, customers report very comfortable sleep, better sleep quality and relief from back pain, with praise for material quality. Some note the firmness feels softer than expected, and one reviewer raised motion transfer from the springs.
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How firm is the Sealy Advantage Memory Essential mattress?
Sealy describes it as medium to firm, so it sits towards the supportive end without being hard. Some owners report it feels a little softer than expected, which is common with memory foam as it warms to your body. Back and stomach sleepers should find it comfortable; very light side sleepers may find it slightly too firm.
Does the Sealy Advantage Memory Essential come with a trial period?
Mattress Online lists a 100-night comfort trial, though it requires you to buy a mattress protector from them at the same time. That's the retailer's own offer rather than a Sealy guarantee, so terms will differ if you buy elsewhere.
How deep is the Sealy Advantage Memory Essential mattress?
It's 27cm deep, made up of a MemorySense memory foam comfort layer over PostureTech Core Support Springs, finished with a knitted cover. That depth suits standard fitted sheets and gives a reasonably substantial feel for the price.
What guarantee does the Sealy Advantage Memory Essential have?
Mattress Online lists a 5-year guarantee on this mattress. It's the retailer's listed term rather than a stated manufacturer promise, so check the guarantee offered wherever you buy.
What sizes does the Sealy Advantage Memory Essential come in?
Five UK sizes: single, small double, double, king and super king, priced from £299 to £559 depending on size. It's handcrafted in the UK and conforms to BS7177: 2008 fire resistance standards.
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