King Size Mattresses — 5ft Pocket Sprung, Memory Foam & Hybrid
Read more
A king size mattress gives a couple more room than a standard double without the floor space of a super king. It's the size many people move up to when they replace a double, and it's the largest choice in this range.
See all mattresses, king size beds, ottoman beds and headboards, or compare double and super king mattresses.
King mattress size
A UK and Irish king size mattress is 5ft, or 150 x 200cm: 15cm wider and 10cm longer than a double. A US king is a different size, so measure inside your bed frame before ordering.
Pocket sprung king size mattress
Many king size mattresses here are pocket sprung, including the Briody VIP range, the Serenity Sleep Aloe Vera and G05 Paradise, which pairs pocket springs with foam, and the Body & Soul Vitality Pillow Top.
Memory foam king size mattress
The Serenity 5ft combines memory foam, which moulds to your shape, with a soft knitted cover.
Hybrid and reversible king mattresses
The Adira range is described as a hybrid of springs and foam. The Serenity Sleep G07 is reversible, so it can be turned over as well as rotated.
Firm king size mattress or soft?
Side sleepers often prefer a softer or medium feel; back and front sleepers often prefer medium to firm. On a bed shared by two different weights, pocket springs give each side its own support.
Looking after a king size mattress
Rotate the mattress head to foot every few months so it wears evenly, and use a mattress protector to keep it clean. A double-sided mattress can also be turned over; a one-sided or pillow top mattress should only be rotated. A new mattress can smell of its fillings for a few days, so let it air with the bedding off.
Delivery
Mattresses are delivered in 2 to 3 weeks unless the product page says otherwise. Our own team delivers across Northern Ireland and the Republic of Ireland and carries the mattress into the room you choose, rather than leaving it at the door.
King size mattress FAQs
What size is a king size mattress?
150 x 200cm, also called 5ft.
How much bigger is a king than a double?
15cm wider and 10cm longer.
Will a king size mattress fit up my stairs?
Measure the narrowest point of the stairs and landing. Our delivery team carries it into the room you choose.