Mattress Size Guide

True Rest mattresses come in three sizes: Single, Double and King. Every size uses the exact same three layer memory foam system, so the only thing that changes between them is how much space you get.

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How Mattress Sizes Are Measured

UK mattress sizes are measured across three dimensions: width, length, and depth. Width and length are standardised, so a Double mattress from any UK retailer will fit a Double bed frame. Depth varies far more between brands, some mattresses are as shallow as 15cm, others 30cm or more, so it's worth checking depth alongside the headline size, not just width and length. Every True Rest mattress is 25cm deep regardless of size, so moving between Single, Double and King changes the fit, not the quality.

Comparison Table

Size	Dimensions (cm)	Dimensions (inches)	Depth
Single	190 x 90cm	75" x 35"	25cm / 10"
Double	190 x 135cm	75" x 53"	25cm / 10"
King	200 x 150cm	79" x 59"	25cm / 10"

Single Mattress, 190 x 90cm

Our smallest size. A good fit for compact bedrooms, box rooms, and guest rooms where floor space is limited. Built with the same three layer foam construction as every True Rest mattress.

View the Single Mattress

Double Mattress, 190 x 135cm

The most common mattress size sold in the UK. 45cm wider than a Single, on the same overall length. Built with the same three layer foam construction as every True Rest mattress.

View the Double Mattress

King Mattress, 200 x 150cm

Our largest size. 15cm wider and 10cm longer than a Double. Built with the same three layer foam construction as every True Rest mattress.

View the King Mattress

Comparing the Sizes

Double vs Single: 45cm wider, same length.
King vs Double: 15cm wider, 10cm longer.
King vs Single: 60cm wider, 10cm longer.

Measuring Your Space

Before you order, it's worth measuring your room and comparing it against your current bed frame or the space you have available. It's also worth checking doorways, hallways and staircases, especially for larger sizes like King, since a compressed mattress in its box still needs room to manoeuvre during delivery.

FAQ

What is the standard UK single mattress size?

190 x 90cm.

What is the standard UK double mattress size?

190 x 135cm.

What is the standard UK king size mattress size?

200 x 150cm.

What's the difference between a Double and a King mattress?

A King is 15cm wider and 10cm longer than a Double.

Do all True Rest mattresses have the same depth?

Yes. Every size is 25cm deep.

Are all True Rest mattresses built the same way?

Yes. Every size uses the same three layer foam construction. Only the dimensions change.

Is a mattress size the same as a bed size?

Yes. In the UK, a mattress size and its matching bed frame use the same name, so a Double mattress is designed to fit a Double bed frame. If you already have a frame, it's worth checking the size before you order to make sure your new mattress fits.

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