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Kingsize Memory Foam Mattresses

If you're tired of not having enough space in bed, the problem could be your mattress. If you want extra room to stretch out in or more space for you and your partner to enjoy, why not choose one of our king-size memory foam mattresses?

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Excellent

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Based on 23,378 reviews

Trustpilot Star rating Verified

We were kept updated all the way through from purchase right up until delivery which was very helpful.

Linda Rudd 11th Jul
Trustpilot Star rating Verified

From ordering to delivery they were very good. Ordering offices very easy, delivery very quick and delivery company very efficient and careful.

Anita B 9th Jul
Trustpilot Star rating Verified

So far so good with the mattress, the quality is excellent and is as described. First class speedy delivery service received and would not hesitate to recommend.

Vicki 9th Jul

Help & Buying Guides

How to choose the best king-size memory foam mattresses

The technology in our king-size memory foam mattresses comes straight from NASA! This should give you full confidence that it is not only created by experts but also effective in promoting better rest.

We're confident that you will enjoy sleep that is truly out of this world on this kind of mattress. Our buying guide section has plenty of information you can use to help you determine whether memory foam will be the right fit for your new bed.

What size is a king-size memory foam mattress?

A king-size memory foam mattress is the same size as a standard king-size mattress, measuring 5 feet wide and 6 feet 6 inches long. Bear in mind that European and specific brands, such as Ikea, have slightly different dimensions and may be an inch or two larger than the standard size.

How much bigger is a king-size memory foam mattress than a double?

A standard double memory foam mattress is 135 x 190cm or 4’6 x 6’3, so a king-size option will be six inches wider and around three inches longer.

Can king-size mattresses fit on double bed frames?

Although they will sit on top of a double bed frame, there will be a certain amount of overhang on the sides and at the foot. This could mean that anyone sitting on the edge of the bed could tip the mattress. A king-size mattress should be partnered up with the correct king-size bedstead to ensure stability and comfort right to the edge of the sleeping area.

How much does a king-size memory foam mattress weigh?

You may find that your king-size memory foam mattress weighs more than you think. When fully expanded (after unboxing and packing), the average king-size memory foam mattress weighs around 100-160 lbs, depending on the density of the foam. The denser the foam, the heavier the mattress, so a king-size firm memory foam mattress will definitely weigh more than your typical mattress! However, you can find boxed king sized memory foam mattresses, such as in our Coolflex range - these rolled and vacuum packed models make it much easier to carry your new bed up the stairs.

Can you get mattress toppers for a king-size memory foam mattress?

Yes. Any standard king-size mattress topper will fit onto a king-size memory foam mattress, giving an even softer and more cushioned feel.

Size Imperial Metric
Cot Mattress 3'9" x 1'9" 120cm x 60cm
Cot Bed Mattress 4'6" x 2'3" 140cm x 70cm
Adjustable Small Single 2'6" x 6'6" 75cm x 200cm
Adjustable Single 3' x 6'6" 90cm x 200cm
Adjustable Small Double 4' x 6'6" 120cm x 200cm
Adjustable Double 4'6" x 6'6" 135cm x 200cm
Small Single 2'6" x 6'3" 75cm x 190cm
Single 3' x 6'3" 90cm x 190cm
Small Double 4' x 6'3" 120cm x 190cm
Double 4'6" x 6'3" 135cm x 190cm
King Size 5' x 6'6" 150cm x 200cm
Super King 6' x 6'6" 180cm x 200cm
European Small Single 2'8" x 6'6" 80cm x 200cm
European Single 3' x 6'6" 90cm x 200cm
European Double 4'7" x 6'6" 140cm x 200cm
European King Size 5'3" x 6'6" 160cm x 200cm

All mattress sizes given are approximate and stated sizes refer to the sleeping surface only. Mattresses sizes may vary slightly from their stated dimensions due to manufacturing tolerances, please allow +/- 2 inches (5cm).

Support Best for
 Icon for Memory Foam Memory Foam Body moulding and pressure relieving
 Icon for Natural Fibres Natural Fibres Unrivalled comfort, naturally temperature-regulating
 Icon for Latex Latex Breathable, supportive and eco friendly
 Icon for Cool Gel Memory Foam Cool Gel Memory Foam Active cooling properties, ideal for hot sleepers
 Icon for Soft White Fibres Soft White Fibres Hypoallergenic polyester, soft and durable

Support Best for
 Icon for Pocket Springs Pocket Springs Individual springs for tailored support
 Icon for Foam Foam Conforms to your body's shape, silent (no springs)
 Icon for Open Coil Springs Open Coil Springs Traditional, interlinked springs
 Icon for Pocket Springs Latex Bouncy yet supportive, great for hot sleepers

Firmness Best for
Softer
Good for side sleepers, a softer level of support
Medium
Good all-rounder for front, side or back sleepers
Medium - Firm
Good for people who change sleeping position
Firm
Good for people who sleep on their front or back
Extra Firm
The firmest level of support, also known as orthopaedic

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