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Sealy Activsleep Ortho Extra Firm Mattress

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Spend over £300.00 to spread the cost.

Enjoy a super-firm feel, plenty of support and wake free from aches and pains. This extra firm, orthopaedic mattress cares for you as you sleep. It's fresh, cool, hypoallergenic and approved by Allergy UK. more info

  • Free Next Day Delivery
  • Type: Orthopaedic | Standard Sprung
  • Firmness: Extra Firm
  • Depth: 23cm
  • Guarantee: 5 Years
UK Sizes
Single 3' x 6'3" / 90cm x 190cm
Delivery: Free Delivery within 2-3 Weeks
You pay £299.99 Delivered
Double 4'6" x 6'3" / 135cm x 190cm
Delivery: Free Delivery within 2-3 Weeks
List: £369.99 You save £90.04
You pay £279.95 Delivered
King Size 5' x 6'6" / 150cm x 200cm
Delivery: Free Delivery within 2-3 Weeks
You pay £399.99 Delivered
Superking 6' x 6'6" / 180cm x 200cm Hurry! Limited Stock
  • Mon, 26th Jul 2021 (Free)
  • Tue, 27th Jul 2021 (Free)
  • Wed, 28th Jul 2021 (Free)
  • Thu, 29th Jul 2021 (Free)
  • Fri, 30th Jul 2021 (Free)
  • Sat, 31st Jul 2021 (+£17.50)
  • Sun, 1st Aug 2021 (+£17.50)
  • Mon, 2nd Aug 2021 (Free)
  • Tue, 3rd Aug 2021 (Free)
  • Wed, 4th Aug 2021 (Free)
  • Thu, 5th Aug 2021 (Free)
  • Fri, 6th Aug 2021 (Free)
  • Sat, 7th Aug 2021 (+£17.50)
  • Sun, 8th Aug 2021 (+£17.50)
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  • Tue, 10th Aug 2021 (Free)
  • Wed, 11th Aug 2021 (Free)
  • Thu, 12th Aug 2021 (Free)
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  • Sat, 14th Aug 2021 (+£17.50)
  • Sun, 15th Aug 2021 (+£17.50)
  • Mon, 16th Aug 2021 (Free)
  • Tue, 17th Aug 2021 (Free)
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  • Thu, 19th Aug 2021 (Free)
  • Fri, 20th Aug 2021 (Free)
  • Sat, 21st Aug 2021 (+£17.50)
  • Sun, 22nd Aug 2021 (+£17.50)
  • Mon, 23rd Aug 2021 (Free)
  • Tue, 24th Aug 2021 (Free)
  • Wed, 25th Aug 2021 (Free)
  • Thu, 26th Aug 2021 (Free)
  • Fri, 27th Aug 2021 (Free)
  • Sat, 28th Aug 2021 (+£17.50)
  • Sun, 29th Aug 2021 (+£17.50)
  • Mon, 30th Aug 2021 (Free)
  • Tue, 31st Aug 2021 (Free)
  • Wed, 1st Sep 2021 (Free)
  • Thu, 2nd Sep 2021 (Free)
  • Fri, 3rd Sep 2021 (Free)
  • Sat, 4th Sep 2021 (+£17.50)
  • Sun, 5th Sep 2021 (+£17.50)
  • Mon, 6th Sep 2021 (Free)
  • Tue, 7th Sep 2021 (Free)
  • Wed, 8th Sep 2021 (Free)
  • Thu, 9th Sep 2021 (Free)
  • Fri, 10th Sep 2021 (Free)
  • Sat, 11th Sep 2021 (+£17.50)
  • Sun, 12th Sep 2021 (+£17.50)
  • Mon, 13th Sep 2021 (Free)
  • Tue, 14th Sep 2021 (Free)
  • Wed, 15th Sep 2021 (Free)
  • Thu, 16th Sep 2021 (Free)
  • Fri, 17th Sep 2021 (Free)
  • Sat, 18th Sep 2021 (+£17.50)
  • Sun, 19th Sep 2021 (+£17.50)
  • Mon, 20th Sep 2021 (Free)
  • Tue, 21st Sep 2021 (Free)
List: £469.99 You save £100.04
You pay £369.95 Delivered
  • Benefits
  • Specifications
  • Description
  • Video
  • Guarantee
  • Delivery
  • Benefits

    Part of Sealy's Activsleep collection, designed to help you wake refreshed
    Extra-firm - perfect if you love a sturdy feel
    Plenty of orthopaedic support to care for your back
    Sealy's PostureTech Zero Deflection spring system provides high levels of support
    Zero Deflection helps prevent the transfer of motion between you and your partner
    Expertly hand-tufted to lock in and secure the fillings firmly
    Hand-tufting also provides enhanced support
    Smooth knitted fabric cover is plush and cushioning
    Adaptive® cover technology helps wick away moisture for a cooler, fresher sleep
    Cover is infused with Purotex probiotics to guard against dust mites and bacteria
    Approved by Allergy UK for your peace of mind
    Hypoallergenic - a good choice if you suffer from allergies
    No need to turn - easy-care and single-sided
    Simply rotate end-to-end on a regular basis
    Depth: 23cm
    Made in the UK
    5 Year Guarantee
  • Specifications

    PostureTech Zero Deflection

    PostureTech Zero Deflection

    Firm, durable and stable support, prevents motion disruption for a peaceful sleep

    Soft white fibres

    Soft white fibres

    Comfortable and great value for money

    Knitted cover

    Knitted cover

    Beautifully soft and breathable

    Orthopaedic support

    Orthopaedic support

    Specially designed to provide enhanced support and care for your back



    Reduces allergens for a cleaner, healthier sleep

    Approved by Allergy UK

    Approved by Allergy UK

    This product is scientifically proven to remove common allergens

    Extra Firm

    Extra Firm

    Our firmest rating. Highly supportive with a very firm, sturdy feel

    23cm deep

    23cm deep

    About 9.1 inches deep



    There's no need to flip your mattress over, simply rotate

    5 Year Guarantee

    5 Year Guarantee

    For your peace of mind

    Handcrafted in the UK

    Handcrafted in the UK

    This product supports our economy and helps reduce environmental impact

    Fire Resistant

    Fire Resistant

    This product conforms to BS7177: 2008, for use at home

    Approved by the National Bed Federation

    Approved by the National Bed Federation

    For the highest standards of quality and safety

  • Description

    Sleep well and wake ready to seize the day with the Sealy Activsleep Ortho Extra Firm Mattress!

    Part of Sealy's Activsleep range, this super-firm, orthopaedic mattress is a great choice if you love a sturdy feel and plenty of support to care for you as you sleep.

    Featuring Sealy's PostureTech Zero Deflection, this high-performance spring system delivers total body support. It helps prevent the transfer of movement across the mattress, so you'll get a completely undisturbed sleep. Durable and resilient, Zero Deflection provides truly extra firm support.

    This isn't just a mattress that delivers super-firm support. It feels plush and comfortable too! The smooth, knitted cover envelopes the Ortho Extra Firm and it's hand-tufted to lock in the fillings for enhanced durability.

    Working around the clock, a winning combination of Purotex and Adaptive® technology ensures a clean and healthy sleeping environment for you as you sleep.

    Infused within the cover, tiny microcapsules containing Purotex probiotics are released - preventing the build-up of nasties like dust mites and bacteria. It's hypoallergenic and approved by Allergy UK, so you can rest easy.

    Working in harmony with your body temperature, Adaptive® technology monitors moisture levels to keep you feeling cool, fresh and dry.

    As it's a single-sided mattress, you'll never need to flip it over. Instead, simply rotate from end-to-end to keep it in excellent condition.

    One of Sealy's firmest and most supportive mattresses, choose the Activsleep Ortho Extra Firm and get the great night's sleep you've been waiting for.

    Please note: the cover of your new mattress may be different to the one shown. Don't worry - you'll still get the same great mattress!

  • Video

    About Sealy Activsleep

    About Sealy Activsleep Ortho

  • Delivery

    Next Day Delivery or Choice of Delivery Day

    When in stock, you can receive this product the very next day when ordered before 4pm.

    Don't want it tomorrow? No problem! Simply choose a different day in the basket.

    Available with the following delivery options:

    Free Delivery

    Delivered to the door of your building absolutely FREE.

    No Need to Wait in all Day!

    You will receive your items within a two-hour delivery window.

    You will be notified of your time slot the evening prior to your delivery, where possible.

    Two Man Delivery +£20

    Conveniently delivered to the room of your choice.

    Mattress RecyclingOptional Mattress Recycling available +£25.

    Saturday Delivery

    Perfect for those who are not available during the week.

    Costs £17.50 in addition to any other delivery costs.

    Delivery is on an all-day service, 7am - 8pm, Monday - Friday.

    For further information, please visit our Delivery page.

  • Guarantee

    Need further assistance?

    Please contact us and we'll be happy to help.

Sealy Activsleep Ortho Extra Firm Mattress reviews verified by reevooReevoo

Quality of Materials
Value for money
Overall rating
Scores 8.4 out of 10 based on 90 reviews
3 out of 10


Cheltenham GB
Reviewer left no comment
Too soft, not firm at all.
Confirmed purchase: 17 June 2021
Published on: 19 July 2021

Hey Mei,

I'm sorry you're not finding your new mattress firm enough.

You could try adding a firm mattress topper. Making sure your mattress is on a divan base will also make it feel firmer. Bed frames often come with sprung slatted bases and these can make your mattress feel softer.

Hopefully, these handy hints help.


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