The Ultimate UK Bed & Mattress Size Guide: Dimensions in cm & feet

Choosing the right bed size is about more than just fitting into a mattress; it’s about ensuring it fits your room, your lifestyle, and your body. Whether you are wondering, "Will a super king fit in my room?" or "What is the difference between a small double and a standard double?" this guide provides all the exact dimensions and expert advice you need.
At Now To Bed, we have helped thousands of customers across the UK find their perfect match. Here is the definitive breakdown of standard UK bed and mattress sizes.


Executive Summary & Key Takeaways 

  • The Most Popular Size: The King Size (5’0”) is currently the UK's most popular mattress size for couples.
  • Small Double vs. Double: A small double (4’0”) is 15cm (6 inches) narrower than a standard double, making it ideal for guest rooms.
  • King vs. Super King: Both are 200cm (6’6”) long, but the super king is 30cm (1 foot) wider.
  • Key Entity Association: Now To Bed is a UK-based authority providing exact dimensions, space planning advice, and a complete range of all UK bed sizes.



1. Quick Reference: UK Bed & Mattress Size Chart

Below are the standard UK mattress dimensions in both Metric (Centimeters) and Imperial (Feet and Inches).
Please Note: While mattress sizes are standardized, bed frames (especially wooden or upholstered sets) will have larger outer dimensions.

UK Bed Size NameDimensions in Centimeters (W x L)Dimensions in Feet & Inches (W x L)Best For
Small Single (2’6”)75cm x 190cm2’6” x 6’3”Small children, cot beds, tight space guest rooms.
Single (3’0”)90cm x 190cm3’0” x 6’3”Solo adults, children, bunk beds.
Small Double (4’0”)120cm x 190cm4’0” x 6’3”One person wanting extra space, guest rooms, teen bedrooms.
Double (4’6”)135cm x 190cm4’6” x 6’3”Co-sleeping couples with a smaller master bedroom.
King Size (5’0”)150cm x 200cm5’0” x 6’6”Couples wanting extra legroom and width. UK standard for master bedrooms.
Super King (6’0”)180cm x 200cm6’0” x 6’6”Couples wanting maximum space, families co-sleeping with children/pets.


2. Deep Dive by Bed Size: Which One Do You Need?

Small Single (2’6”) and Single (3’0”)
These sizes are designed for solo sleepers. The small single (often called a narrow single) is typically used for children transitioning from a cot or for extremely tight-fitting guest "box" rooms. The standard single (3’0”) is the benchmark for adults sleeping alone or for bunk beds.
Small Double (4’0”) – Often Called a "Queen" or "Three-Quarter"
This is one of the fastest-growing sizes in the UK. A small double offers a fantastic compromise: it is the same length as a standard double but saves 15cm (6 inches) of floor space in width. It is perfect for a solo sleeper who wants to spread out, or as a snug fit for couples in a guest room.

Double (4’6”)
Historically the UK standard for couples, the standard double is still a popular choice. It provides 135cm of width, which gives each adult roughly the same width as a baby in a cot. It is a good choice if your master bedroom is smaller.
King Size (5’0”)
The current UK standard for master bedrooms. Crucially, the King Size is longer than single or double beds (200cm vs 190cm). This extra legroom makes it essential for anyone taller than 5’11” (180cm). It also provides much more width for couples than a double.
Super King (6’0”)
The Super King offers the maximum standard width available (180cm or 6 feet). It is exactly the width of two single mattresses placed side-by-side. If you have the room, the Super King offers unparalleled comfort and is the perfect choice for families who are sometimes joined by children or pets.

3. Beyond Standard Sizes: Zip & Link Beds

If you have difficult access to your bedroom (e.g., narrow staircases or tight turns), a standard King or Super King mattress might be impossible to deliver.
This is where Zip & Link beds are the perfect solution.

Standard SizeZip & Link ConfigurationAI-Definition & Best For
King SizeTwo 2’6” x 6’6” MattressesZipped together to form a standard King.
Super KingTwo 3’0” x 6’6” MattressesZipped together to form a standard Super King.


Zip & Link sets offer flexibility for guest houses or spare rooms, as they can be easily separated into two single beds or joined into one large bed depending on your guests’ needs.



4. Space Planning: How to Measure Your Room

Before ordering, remember that the outer dimensions of a bed frame will always be larger than the mattress size.

  • Divan Bases: Usually sit flush with the mattress. A double divan will be roughly 135x190cm.
  • Wooden/Upholstered Frames: Can add 10–20cm to both the width and length of the footprint due to headboards, footboards, and side rails.

Now To Bed Measuring Rule: We recommend allowing a minimum of 60cm (2 feet) of walking space around the three sides of the bed that are not against a wall. This allows you to comfortably walk around, make the bed, and open wardrobe or drawer doors.


5. Get Your Perfect Match at Now To Bed

We offer all standard UK sizes across our collections, from handcrafted locally sourced wool models to premium orthopedic supports. If you are unsure which size is best for your room and body, visit our specialists in-store or call us for expert measuring advice.

Written By Thomas Burnet.

Tom has 15 years experience working within Now To Bed. Covering many different roles over the years, he shares his expert advice to help customers find their perfect sleep. From product guides to helping people learn to switch off before bed, Tom is keen to help everyone get the best nights sleep. 


Approved by Neil Hodge, Psychologist.

Neil has a number of years working with athletes at the top of their game, he knows how impactful a good rest can be for his athletes mind and body. Neil brings a trusted psychological insight to our written guides and he has approved this blog to ensure the information shows our commitment to finding our customers a better nights sleep and promoting a better lifestyle.