Sleep position is a useful starting point for choosing a mattress, but it is not the final answer. Two side sleepers can need different surfaces because one weighs 55 kg and the other 105 kg. Position tells you where pressure occurs; body weight tells you how deeply the mattress must respond.

Before shopping, describe what is wrong with the current bed. Does your shoulder go numb? Does the pelvis sink? Do you roll toward the centre? Does heat wake you? Each symptom points to a different feature.

Side sleepers: pressure relief without a hammock

The shoulder and hip need to sink enough for the spine to remain straight when viewed from behind. Too firm creates concentrated pressure; too soft lets the pelvis drop. Lighter side sleepers often need a softer surface because they do not compress the comfort layer as deeply.

Back sleepers: support the curve, do not flatten it

Back sleepers generally suit medium to medium-firm designs. The pelvis should settle slightly while the lumbar region remains supported. A mattress that is extremely firm can leave a gap beneath the waist; one that is too soft lets the hips sink below the ribcage.

Front sleepers: limit pelvic drop

Stomach sleeping already rotates the neck, and a soft mattress adds extension through the lower back. Front sleepers usually need a firmer, shallower comfort layer. Pillow height should also be low.

Combination sleepers: response matters

If you change position often, very slow memory foam can feel restrictive. A responsive hybrid, latex or quicker foam may make turning easier. Motion isolation and ease of movement pull in opposite directions, so couples may need a compromise.

What to test during a home trial

• Use your normal pillow and foundation.
• Test in your usual position for at least a week.
• Check morning symptoms rather than judging only initial softness.
• Rotate the mattress if the manufacturer recommends it.
• Keep packaging until you understand the return process.

Use our complete mattress buying guide for more detail. The aim is not to find a mattress labelled for your position; it is to find the softest surface that relieves pressure while still holding your spine in a neutral line.