by Quick answer: Most back sleepers feel best on a medium-firm mattress, roughly 6 to 7 on a 10-point scale. That level keeps the hips from sinking too far while still letting the lower back stay gently supported, which helps the spine hold its natural curve.
By the MattressNut editorial team · Updated June 2026
Best Firmness for Back Sleepers — The Short Answer
A back sleeper's weight is spread fairly evenly, so the goal is a surface that supports the hips and shoulders while filling the small gap under the lower back. Medium-firm does that for most people. Too soft and the hips drop; too firm and the lower back can feel unsupported.
What Matters Most
Firmness is partly personal, and body weight changes how a mattress feels. Lighter people often find a given mattress feels firmer, while heavier people sink in more and may prefer something on the firmer side. Comfort and support both matter, so use medium-firm as a starting point and adjust from there.
Quick Reference
| Factor | Detail |
|---|---|
| Typical sweet spot | Medium-firm, about 6–7 of 10 |
| Why it works | Supports hips while cradling the lower-back curve |
| Lighter bodies | May prefer slightly softer feel |
| Heavier bodies | Often prefer a touch firmer for support |
Practical Tips
Lie on your back the way you actually sleep and check whether your lower back feels supported, not arched or strained. A good mattress lets you slide a hand under your lower back with light resistance. If you wake with stiffness, the surface may be too soft or too firm for you. Persistent back pain is worth discussing with a doctor.
Our Recommended Mattress
For back sleepers, the Saatva Classic in its Luxury Firm option lands right in that medium-firm range that suits most back sleepers. It's a luxury innerspring-hybrid with coil-on-coil support, so it holds the hips up while the comfort layer eases pressure under the shoulders and lower back. Strong edge support and a 365-night home trial give you time to confirm it fits how you sleep.
See the Saatva Classic and its 365-night trial
The Bottom Line
Start at medium-firm and adjust based on your weight and how your lower back feels in the morning. The right surface supports your spine without forcing it flat or letting your hips sink.
Bottom line: Most back sleepers do best on a medium-firm mattress around 6–7 of 10.
Related: our full Saatva mattress review and best mattress for back pain.