King Size Mattresses – Luxury Comfort, Premium Support & Spacious Sleep

Discover the perfect king size mattress at Mattresses365, designed to provide exceptional comfort, superior support and a more luxurious sleeping experience. As one of the UK's most popular premium mattress sizes, a king mattress offers generous sleeping space for couples and those who enjoy extra room at night.

Our collection includes a wide choice of king pocket sprung mattresses, memory foam mattresses, hybrid mattresses and rolled mattresses from trusted UK manufacturers. Whether you prefer the responsive support of pocket springs, the pressure relief of memory foam or the balanced comfort of a hybrid design, we have a king mattress to suit your sleep preferences.

Ideal for couples wanting extra sleeping space
Premium mattress options for master bedrooms
Available in soft, medium and firm comfort levels
Wide range of pocket sprung, memory foam and hybrid designs
Selected models available with Next Day Delivery

Choosing the Right King Size Mattress

A king size mattress is a popular choice for those looking to upgrade their bedroom with additional comfort and space. Measuring approximately 5ft wide (150cm x 200cm), a king mattress provides more room than a standard double mattress while offering excellent support for couples and individual sleepers.

When choosing a king size mattress, consider your preferred sleeping position, firmness level, support needs and mattress materials. Our collection features traditional pocket sprung mattresses, advanced memory foam designs and premium hybrid mattresses created for long-lasting comfort.

Need Help Choosing Your King Size Mattress?

Choosing the right king mattress can make a significant difference to your sleep quality. Our expert guides help you understand mattress materials, firmness options and the differences between UK mattress sizes.

Whether you are upgrading your master bedroom, replacing an older mattress or looking for a more luxurious sleeping experience, our advice guides make finding the perfect king size mattress easier.

Mattress Buying Guide

Learn about mattress materials, support systems, firmness ratings and the key features to consider before choosing your new mattress.

Explore Our Mattress Buying Guides →

Mattress Size Guide

Compare UK mattress sizes and understand the differences between double, king and super king mattresses.

View Our Mattress Size Guide →

King Pocket Sprung Mattresses

King pocket sprung mattresses feature individually wrapped springs that move independently to provide tailored support across the mattress. They offer excellent airflow, reduced partner disturbance and a premium supportive feel, making them a popular choice for larger beds.

King Memory Foam Mattresses

King memory foam mattresses provide a luxurious, body-contouring feel by moulding to your shape and helping relieve pressure points. They are ideal for sleepers who prefer a cushioned and supportive sleeping surface.

King Hybrid Mattresses

King hybrid mattresses combine advanced spring systems with comfort layers such as memory foam, latex or cooling materials. They provide the perfect balance of responsive support, comfort and breathability.

King Rolled Mattresses

King rolled mattresses are compressed and carefully packaged for convenient delivery. They provide an easier setup solution while still offering excellent comfort and support once fully expanded.

Who Is a King Size Mattress Suitable For?

Couples – Provides extra sleeping space and improved comfort for two people.
Master Bedrooms – A premium choice for creating a comfortable and luxurious bedroom setup.
Taller Sleepers – Offers additional length compared with a standard double mattress.
Single Adults – Perfect for those who enjoy maximum sleeping space.
Luxury Sleep Seekers – Ideal for anyone wanting a more spacious and premium sleep experience.

What Firmness King Size Mattress Should I Choose?

Soft King Mattresses – Designed for sleepers who prefer a softer, more luxurious cushioned feel.
Medium King Mattresses – The most popular firmness choice, offering an excellent balance of comfort and support.
Firm King Mattresses – Suitable for sleepers who prefer enhanced support and a more stable sleeping surface.

King Size Mattress Size Guide

A standard UK king size mattress measures approximately: 150cm wide x 200cm long (5ft x 6ft6").

A king mattress provides significantly more sleeping space than a double mattress, making it a popular choice for couples who want additional room and improved comfort.

Always measure your bed frame carefully before ordering to ensure your new king size mattress fits correctly.

Why Buy Your King Size Mattress From Mattresses365?

At Mattresses365, we offer a carefully selected collection of king size mattresses from trusted manufacturers, helping you create a more comfortable and luxurious bedroom environment at competitive prices.

✔ Premium range of king size mattresses

✔ Pocket sprung, memory foam and hybrid options

✔ Trusted UK mattress manufacturers

✔ Competitive prices on quality mattresses

✔ Next Day Delivery available on selected models

✔ Manufacturer guarantees included

✔ Expert mattress advice and support

King Size Mattress FAQs

What size is a king size mattress?

A standard UK king size mattress measures approximately 150cm x 200cm (5ft x 6ft6").

Is a king size mattress better for couples?

Yes. A king size mattress provides more sleeping space than a double mattress, making it an excellent choice for couples who want additional comfort and freedom of movement.

What is the best king size mattress?

The best king size mattress depends on your preferred comfort level, sleeping position and support requirements. Pocket sprung mattresses provide responsive support, while memory foam offers pressure relief and a more moulded feel.

Should I choose a medium or firm king size mattress?

Medium king mattresses are the most popular option because they provide a balance of comfort and support. Firm mattresses are better suited to sleepers who prefer a stronger supportive feel.

Are king size mattresses available with next day delivery?

Many king size mattresses are available with next day delivery depending on the specific model selected.