A firm mattress has very little give, so you lie on top of it rather than sinking in. It suits front sleepers, people who like a solid, supportive bed and anyone who finds softer mattresses too warm or too hard to move on.
Our firm mattresses
- OrthoSupport: 23cm, heavy-gauge coil springs with deep fillings and turning handles.
- MemorySupport: 25cm, firm coil springs under a memory foam layer, so it feels a little kinder on top.
- Copper Crest 2000: 25cm, 2000 pocket springs with memory foam, the firmest in our Copper range.
All three are full-depth mattresses for floor-level beds and divans, in single to super king.
Who is a firm mattress best for?
Front sleepers, and people who like to feel held up rather than cushioned. Lying on your front, a soft mattress lets the hips sink and arches the lower back. A firm surface keeps you flatter. Side sleepers usually find firm too hard at the shoulder and hip, and are better on medium.
Is a firm mattress good for a child?
Most children do better on medium or medium-firm. Children are light, so a firm mattress can feel harder to them than it does to an adult. For children's beds, see our medium-firm mattresses and bunk bed mattresses.
Firm or medium-firm?
Firm has almost no surface give; medium-firm adds a comfortable top layer. If you're unsure, medium-firm is the safer choice for most sleepers.
How we rate firmness
We rate every mattress from 1 (softest) to 10 (firmest):
- Medium-soft: about 4.
- Medium: 5 to 6.
- Medium-firm: 7.
- Firm: 8 to 9.
Firm mattresses: common questions
Is a firm mattress better for back pain?
Not always. Many people with back pain prefer medium-firm. Comfort is personal, so speak to a health professional if pain persists.
Can I make a firm mattress softer?
Yes, with a mattress topper.
Do firm mattresses last longer?
Firmness and lifespan aren't the same thing. How a mattress is made and looked after matters more. Rotate it every few months.
Not sure which to choose? Message our family team with your bed's size and the maximum mattress depth on its product page, and we'll point you to the right mattress.
Written by the Millie & Jones family team. Last updated October 2026.
