Small bedroom or a solo sleeper? Then a single mattress is probably just what you need. We have a limited selection of small single mattresses which measure 75cm x 200cm available at great prices. This is the nearest equivalent to what used to be traditionally known as a half king mattress. Two side by side equal a standard king size. Scroll to the foot of this page for more tips to help you pick the right option. * Please note, from 01/04/2020 mattresses featured here are included in our 100 night trial.