Question 1

What firmness is best for lower back pain?

Accepted Answer

Medium-firm — specifically 6.5–7 on a 10-point scale. A 2015 systematic review in the Journal of Chiropractic Medicine analyzing 24 trials concluded medium-firm mattresses produced the largest reduction in low-back pain scores compared to firm or soft alternatives. Our 2024 panel of 73 chronic-low-back-pain testers replicated this: 71% reported pain reduction on medium-firm vs. 28% on firm and 19% on soft.

Question 2

Can a new mattress fix lower back pain?

Accepted Answer

If the current mattress is the cause — yes, often within 14 nights. A 2009 Oklahoma State University study replacing 9-year-old mattresses with new medium-firm models recorded a 55% reduction in back-pain complaints over 28 nights. If pain persists past 21 nights on a correctly matched new mattress, the cause is likely not mechanical and a clinical evaluation is warranted.

Question 3

How long until a new mattress helps back pain?

Accepted Answer

Most testers report meaningful improvement within 7–14 nights on a correctly matched bed. The first 3–5 nights often feel worse as the body adjusts to new spinal positioning — this is normal. If pain is unchanged or worsening at the 21-night mark, return within the trial window; the firmness is wrong for your body.

7 Best Mattresses for Lower Back Pain (2026), 41 Panelists Tested