How to Choose a Mattress: A Method, Not a Ranking
The reason mattress shopping is exhausting is that everyone starts with the products. Start with the six decisions instead and the catalogue shrinks fast.
1. Size — decide the frame first
Everything else depends on it, and it is the only decision with a hard constraint. Measure the internal opening of the frame, not the old mattress. If nothing standard fits, that is a made-to-measure job and not a compromise.
Every UK size in cm and inches →
2. Firmness — from how you sleep, then your weight
Position sets the range: side 4–6, back 5–7, front 7–8. Weight shifts it: under 60 kg go a step softer, over 95 kg a step firmer. That is the whole rule, and it gets you within one point.
3. Do you share the bed?
If yes, motion isolation moves to the top of the list and that means pocket springs. If there is a large weight difference between you, read the couples guide before anything else — the answer may be two linked singles rather than one mattress.
4. Do you sleep hot?
If yes, this rules out a deep memory foam comfort layer and points at latex, natural fillings, or memory over springs rather than over a foam block.
5. Now, and only now, the construction
By this point three or four decisions have already eliminated most of the range. What is left is a preference between feels:
- Memory foam — most contour, slowest, warmest.
- Latex — fast, cool, durable, heavier and dearer.
- Pocket sprung — support and isolation; the comfort layer decides the feel.
- Open coil — firm, cheap, cool, moves as one surface.
- Natural fillings — best temperature regulation, longest life, highest price.
The five constructions compared →
6. Depth — check the frame, not the price list
Measure from your slats to the top of the side rail. A mattress much deeper than the surround loses the edge support the frame was giving it; much shallower and the rail sticks up. On a bunk, the safety rail has to stand at least 16 cm above the sleeping surface, which usually caps you at 15 cm.
Three things that are not worth deciding on
- Spring count above about 1,500 in a double. Thinner springs, same total work.
- "Orthopaedic". No standard behind the word. It means firm.
- Cooling covers. Real, small, and no substitute for what the mattress is made of.
Then give it a month
Any new mattress feels wrong for two or three weeks, because your body has adapted to the old one. Judge it at week four. A 100-night trial exists precisely because a fortnight is not long enough to know.
If you would rather answer questions than read
The finder on the homepage asks the six questions above and hands you the filtered range. It takes about a minute and nothing is stored.