When it comes to UK bed sizes you will probably be familiar with the 6 standard bed sizes that are commonly advertised for the UK market; Small Single, Single, Small Double, Double, King & Superking. When you see these advertised it can be easy to fall into the trap that all beds are created equally, or at least sized equally.
With regards to the mattress sizing, it would be great for companies like us who manufacture and sell beds if it was the case that all were the same size. Unfortunately given the varying different mattress types available and also a large number of mattress manufacturers this isn’t always going to be the case.
As it turns out most foam mattresses are very close which is quite easy to do as they are just cut from blocks of foam. But then a large proportion of spring mattresses are made by hand, hand-filled hand-tufted and hand-stitched. So, as close as you can get it is impossible for it to be exact. We know this as we have a mattress factory and as much as we wish we could get them all exact to the cm but it just isn't possible with a hand-stitched item, even with the utmost care there will always be at least a couple of mm variation.
The other slight issue being there are actually 2 sets of standard sizes of UK mattresses and they do not quite exactly align.
UK mattresses are traditionally;
2ft6 x 6ft3 - Small Single
3ft x 6ft3 - Single
4ft x 6ft3 - Small double
4ft6 x 6ft3 - Double
5ft x 6ft6 - King
6ft x 6ft6 - Superking
But we also now have metric sizes for beds;
75cm x 190cm - Small single
90cm x 190cm - Single
120cm x 190cm - Small double
135cm x 190cm - Double
150cm x 200cm - King
180cm x 200cm - Superking
These numbers are very close to each other but are not exactly the same. You can do the conversions and compare them to see it's so close it is generally a non-issue and not something that is ever really mentioned. But it means as a bed manufacturer we have to be wary that our beds fit both sizes and not just align to the size of the mattresses we sell but also those mattresses from other suppliers.