How Big is a King Size Memory Foam Mattress?
King size mattress dimensions are 150cm x 200cm or 5’0 x 6’8.
Make sure you choose a king size bed frame to match.
Why Choose a King?
Ideal for couples and those who often share their bed with children and pets - a king size mattress is an excellent option if you need some extra wiggle room.
It allows you to sleep comfortably without disturbing your partner and will fit nicely into most double bedrooms.
Want to go even bigger? Check out our favourite super king mattresses.
What's the Best King Size Memory Foam Mattress?
The right mattress for you depends on a variety of factors, such as your individual sleeping habits, whether you sleep alone or with a partner, and the level of support your body requires.
Consider the following factors;
- Your preferred sleeping position
- Your body weight - the heavier you are, the higher level of support needed
- Your budget
- Any sleep issues you have (overheating, back pain…)
- Style preferences
- Comfort preferences - do you prefer a firm or soft sleep surface?
Let’s delve a little deeper.
Choosing the Right King Size Mattress
You may have decided on the size, but there are many factors you need to consider to help you pick your perfect fit.
Here’s a quick mattress buying guide to help you weigh things up.
Memory Foam Density
Usually, a mattress with high memory foam density will feel more solid and provide more support to heavier people.
When choosing - consider your preferences, do you like your mattress firm or soft?
Stomach sleepers should consider opting for a high density surface that isn’t too soft, as this could accentuate the curve in your spine, leading to lower back pain. Side sleepers on the other hand, or those who move around a lot at night should opt for something softer to provide cushioning around joints.
Price Range
What’s your budget? Keeping this in mind will help you figure out how to choose a mattress. The good news is, we have plenty of more affordable king size options thanks to our factory direct pricing.
Bedroom Size
It’s always a good idea to check the measurements of your bedroom to be sure the bed will easily fit. Ensure you’ll be left with enough space to move around the room!
Your Partner
Do you and your partner have significantly different body weights? Does one of you tend to overheat at night?
If sharing this bed with someone else - consider both of your habits. Doing so will make sure you both get a good night’s sleep.
Sleep Issues
Do you suffer from any conditions that can disrupt your sleep? From arthritis to back pain - there’s a mattress out there to help.
To ease back and joint pain, try an orthopedic memory foam mattress, or check out our list of best mattresses for heavy people to find the right level of support for you.

Cost of Our King Size Mattresses
When it comes to mattresses, price tags can vary wildly - but how can you tell if you’re buying quality?
We offer direct to consumer prices to deliver high quality memory foam products at everyday prices. Made in UK factories, we pass on shipping and process savings to our customers.
Our king size mattresses vary in cost from £139.99 - £679.99. These prices reflect the materials used and the thickness of the foam.
Best Value King Size Memory Foam Mattress
Our Essentials king size mattresses are excellent value for money. Offering firm, hypoallergenic support and three layers of comfort for just £139.99.
Best Luxury King Size Mattress
If you’re looking for something special, our 4G Aircool Ultra memory foam mattress features Eucalyptus infused fabric, cooling sleep technology and deep layers of memory foam for £679.99.
Understanding Our Range of King Size Mattresses
We understand that sleeping experiences are personal, with everyone having different habits and preferences. Our wide range of mattresses reflects that.
Coolmax
Our cool memory foam mattresses are perfect for those who overheat during the night, as the fibres have been specifically designed for breathability.
Essentials
Our Essentials memory foam range is our most basic, yet still offers optimum comfort. Here you can find the most affordable prices, without compromising on quality.
4G Aircool
Our foam 4G Aircool mattress range has been specifically designed with breathability in mind. As you sleep, the increased airflow will ensure you don’t overheat.
These mattresses also feature eucalyptus infused covers, making them luxuriously soft to the touch.
Zen
Mattresses found in our Zen range combine various levels of memory foam to help ease joint pain, align your spine and ensure you sleep without tension.
Memory Foam King Size Mattresses
Memory foam mattresses offer:
- Pressure relief
- Lumbar support
- Body contouring
- Hypoallergenic materials
This type of mattress is ideal for back pain sufferers and those who enjoy a cushioning feeling.
Pocket Sprung King Size Mattresses
Pocket sprung mattresses contain individually encased springs that respond to your movement throughout the night. This type of mattress is a good choice for couples of different weights and for those who enjoy the bounce of springs.
Hybrid King Size Mattresses
Get the best of both worlds with a hybrid mattress combining springs and layers of foam for ultimate comfort and support. Hybrid mattresses can be great for alleviating different sleep issues as they combine different advantages in one.

Perfecting Your Sleeping Space
Add the finishing touches with our sleep essentials.
King Size Memory Foam Mattress Toppers
Memory foam mattress toppers not only keep your mattress protected, they also make your bed luxuriously soft to sleep on.
An extra layer of comfort never goes amiss!
Our Mattress Sizes
Looking for a different size?
We offer a wide range of other options, including:
- Small single mattresses
- Single mattresses
- Small double mattresses
- Double mattresses
- Super king mattresses
Why Choose Us?
Get easy next day delivery options, a 100 night sleep trial on selected products and generous warranties.
At Memory Foam Warehouse, we specialise in bringing you comfort at affordable prices. We believe everyone deserves the perfect night’s sleep, which is why we only cut prices - not corners!
Buy a mattress online here.