mattress online mobile
Sealy Activsleep Ortho Posture Firm Support Mattress Rated 3/5 based on 66 customer reviews

Sealy Activsleep Ortho Posture Firm Support Mattress

Brand: Sealy
Firmness: Firm Mattress

3/5 - 66 Read Reviews


Small Double
King Size
Super King

*We work with retailers direct to secure the best deals. Outgoing links on our site are monetised

wizard icon
wizard banner
Is the Sealy Activsleep Ortho Posture Firm Support Mattress suitable for you? Find out!
Take Quiz

What Makes The Sealy Activsleep Ortho Posture Firm Support Mattress Great

I am a post-natal mother with a five-month old baby and my back has obviously taken a bit of a hammering recently what with the breastfeeding and constantly picking up a baby. Therefore, I was looking for a very firm and supportive mattress, which is exactly what I got. It has been a game-changer. Also, I bought it during the Covid-19 pandemic and it only took a few days to be delivered from 7 hours away - excellent logistics. Even better, I paid £20 and they took the old mattress away and not to landfill. I also didn??t realise all the eco-credentials of the mattress before it arrived - be sure to check these out. I will definitely be buying my next mattress from this company - credit where credit is due.


This product is unlikely to cause any sort of allergic reaction. Ideal if you suffer from any sort of allergy problems

Made in the UK

These are made and manufactured in the UK, meaning that they all meet the same exceptional quality and durability that we expect from genuine UK manufacturing.

Depth: 24cm

Most experts recommend a minimum 10 inches, 4 inches on the top layer and 6 inches for the core so this size is an ideal balance of size and performance. Generally, the heavier the load the deeper the mattress should be.

5 year guarantee

A 5 year guarantee is quite rare in the industry and is a great indicator of the retailer beleiving in their product. Anything go wrong in the next 5 years, no drama, get it replaced.

Handcrafted in the UK

Handcrafted in the UK means that the product is built here, by people being paid a fair and honest wage using certified and safe products of good quality and construction. UK manufacturing is some of th best in the world and all of that is reflected in this product

Orthopaedic Support

Do you suffer from back pain? If so you will likely find that an orthopaedic mattress will be massively beneficial to you. Slightly firmer in the comfort side of things but ultimately with a better support layer means that your back and neck will thank you for years to come.


Firm mattresses are great for those looking for an extra bit of support, either because they have a higher BMI and leanm toward the heavier side, or because they have joint and muscle pain and appreciate a decent amount of support while they sleep. If you are not actively looking for a firm mattress it may be wise to consider something else from the range that is perhaps closer to the medium firmness rating

Knitted Cover

It is common in the industry to have a knitted cover, these covers can come in a variety of patterns but are typically hard wearing and do not present problems for consumers.

24cm deep

A depth of 24cm is about right for a good quality mattress. While the depth of a mattress is not necessarily a guarantee of quality, you typically cannot get the best comfort and suport out of a thin mattress

Soft white fibres

White fibres tend to be a mixture of polester and other non-descript synthetic fibres


Single sided means only one side is comfy. Positives are you only need to rotate the mattress occassionaly rather than the more cumbersome rotate and flip. Downside is the lifespan of the product may suffer as a result, only marginal, but worth mentioning.

Part of Sealy's Activsleep mattress range - designed for a healthy, active lifestyle

An orthopaedic and highly supportive mattress

Ideal if you love a firmer feel

Featuring Sealy's PostureTech Core Support spring system

Core Support delivers plenty of support to the areas you need it most

Smooth knitted fabric cover provides a plush, cushioned feel

The cover is micro-quilted to secure the fillings and improve durability

Adaptive technology keeps you cool, fresh and dry as you sleep

Approved by the National Bed Federation

The NBF is one of the most prestigious awarding federations in the industry, helped slightly by the fact that it is one of the only, however, it is still a great source of comfort knowing that this product holds approval by the team

Approved by Allergy UK

If you have allergies then you may want to consider a mattress like this. Approved by Allergy UK, this product has fillings that are approved for those that suffer from a host of common allergies and while there is no guarantee that this product will prevent allergies, it should prevent further problems for those that do suffer

Purotex probiotics are infused within the cover and help prevent bacteria and dust mites

The clever cover technology provides a cleaner, fresher mattress feel

Hypoallergenic and approved by Allergy UK for your total peace of mind

Single-sided mattress and easy to care for - no need to turn over

Fire Resistant

Fire resistant does not mean the product will never catch fire, rather, it will not go up in flames quite so quickly. Resistant to fire in the same way that I am resistant to kisses, sooner or later you end up giving in.

PostureTech Core Support Springs

Providing even weight distribution, the PostureTech spring system feels soft then gradually gets firmer as pressure is applied. The entire spring unit is twice tempered, making it strong. Their Smaller diameter means they can fit more into an area, allowing for a more fine-tuned level of support.

Customer Reviews For The Sealy Activsleep Ortho Posture Firm Support Mattress

Based on 66 review

This was one of the cheaper mattresses I assessed before buying but was convinced by the positive feedback from others. I have not been disappointed. I bought the zip and link super kingsize. I have already recommended it to a friend. I would also add that the delivery lads were excellent, they made sure I was happy and took away all the packaging.

5 more back ache, for both myself and husband!The top of the mattress is soft yet supportive - it doesnt mould rather holds and cushions you. It is not overly firm. We are very pleased with it and should have changed our mattress a couple of years ago which was similar.


Fantastic mattress. Ive had memory foam and most recently a Hypnos and all gave me unexplained back and hip pain. From the first night of sleeping on this sealy mattress no pain at all. Great quality, great price wouldn??t go anywhere else now for a new mattress.


The mattress is really comfortable, I have a very sore hip and I suffer from a twist in my spine. The mattress I had I was unable to get a full nights sleep on but now I sleep through the night. (dont want to get up).


I suffer with a rare genetic joint condition. And struggle with sleep due to pain. Have been through several mattresses, but this 1 finally has given me some relief. It supports my spine and hips well. Highly recommend.


The mattress is extremely well made and comfortable. It supports in all of the right places. Best sleep in a long time. SEALY mattresses are quality and I would definitely purchase again.


Very comfortable and the gentle support for my spine has been great. My sciatica and shoulder are grateful for this choice.


Extremely supportive and comfortable. The foam quilted surface ??disguises?? the firmness of the underlying springs.


Zip and link: Super king size.Easy to get up my narrow staircase.Lovely and big.Very comfortable.Highly recommend.


Ive been sleeping very well on this mattress.I need a mattress with good support in order to avoid backache.


Super comfy and a great nights sleep. I can get in and out of bed without disturbing the other half :)


Always have a Sealy mattress and this one is very good. Medium to firm so not too hard to lie on


This mattress supports your bodies weight were needed I??m pain free from night time sciatica.


Really comfortable, easy to turn yourself and also helps you bounce out of bed.


Best mattress I??ve ever had,it??s support and comfort is amazing ��


Seriously comfortable. Good quality. Excellent value for money.


So comfortable, not too high and at cost that is very reasonable.


Love the finish of the mattress, beautifly soft and smooth


Unbelievably comfortable. Slept like a log from night one.


Firm support,very comfy,just right for me,excellent valve


Lovely firm supportive mattress. Amazing price and size.


Love the full body support I get from this mattress.


It is firm enough for us and supportive for our back


Excellent quality. Well made. Very comfortable.


Extremely comfort and inexpensive. Very pleased.


Very comfortable. Getting good nights sleep now


Good solid support.Nice and firm for my back.


Lovely top to mattress, a bit of luxury.


Very comfortable. Great nights sleep


Very comfortable, quality materials.


Comfortable from the first night


Very supportive and comfortable


Feels good n adequately firm


Excellent quality and price


Great deal would recommend


so far everything is good


Look of mattress is good


It??s comfortable enough


Perfect, as described.


Very comfortable


Good night sleep


It looks good



Customers Also Purchased

Latest Advice and Guides → Your Questions Answered

Everything You Need To Know About Mattress Fillings
Soft and Squishy Memory Foam
Simple Mattress Buying Guide