Diamond Rock Extra Firm 12" Mattress
From $30/mo with 0% APR
An extra firm mattress rates 9–10 on the firmness scale — the maximum resistance available. Designed for stomach sleepers, heavier individuals over 250 lbs, those with specific back conditions, and anyone who finds standard firm mattresses still too soft. We carry 8 extra firm mattresses across hybrid and innerspring constructions. All sizes in stock. Price range $449–$2,499.
8 extra firm mattresses available
From $30/mo with 0% APR
From $34/mo with 0% APR
From $34/mo with 0% APR
From $36/mo with 0% APR
From $41/mo with 0% APR
From $71/mo with 0% APR
From $96/mo with 0% APR
From $130/mo with 0% APR
Extra firm is a specialized firmness level — not a general preference. It is the correct choice for a specific set of sleepers with distinct support requirements.
Stomach sleeping requires maximum hip support to prevent hyperextension of the lower back. If the hips sink into the mattress, the lumbar spine arches backward and creates significant strain. An extra firm mattress keeps the hips level with the shoulders, maintaining the spine in a straight horizontal plane — the only way stomach sleeping can be sustainable long-term.
At 250 lbs and above, even a firm mattress (7–8/10) can compress more than expected, resulting in a feel closer to medium. Extra firm mattresses are engineered to provide true resistance at higher body weights, ensuring the support level does not diminish under compression. Sleepers in this weight range who have found firm mattresses still too soft will typically find extra firm delivers the resistance they need.
Certain spinal conditions — including some forms of spondylolisthesis, ankylosing spondylitis, or post-surgical recovery protocols — may require a maximally firm sleeping surface as directed by a physician or physical therapist. If you have been advised by a healthcare provider to sleep on the firmest surface available, extra firm is the appropriate starting point. Always confirm with your provider before selecting a mattress for a medical condition.
Some people sleep on the floor by preference or habit and find standard mattresses too soft. An extra firm mattress provides the flat, rigid surface most similar to floor sleeping while offering a proper foundation and eliminating the cold, hard floor contact. It is the most practical first step for floor sleepers who want to transition to a bed without losing the feel they are accustomed to.
Mattress firmness is measured on a scale from 1 to 10. Extra firm mattresses rate 9–10, placing them at the absolute firmest end of the spectrum — no comfort layer, maximum resistance, minimal contouring.
Deep contouring. Best for side sleepers under 150 lbs.
Shop PlushMost PopularMedium4–6/10The most versatile firmness. Works for most sleep positions.
Shop MediumFirm7–8/10Solid support with minimal sinkage. Best for back and stomach sleepers.
Shop FirmYou are hereExtra Firm9–10/10Maximum resistance. Designed for stomach sleepers, heavy sleepers, and specific therapeutic needs.
Extra firm is the firmest mattress available. The table below compares it against the next softest option so you can understand exactly what separates 7–8 from 9–10.
| Firm | Extra FirmThis Page | |
|---|---|---|
| Firmness Scale | 7–8 / 10 | 9–10 / 10 |
| Best Sleep Position | Back, Stomach | Stomach |
| Body Weight | 180–280 lbs | 250+ lbs |
| Sinkage | Minimal | Very minimal |
| Comfort Layer | Thin comfort layer present | Near-zero comfort layer |
| Motion Isolation | Moderate | Low |
| Edge Support | Strong | Very strong |
| Cooling | Good | Excellent |
| Back Pain Relief | Strong for back/stomach sleepers | Stomach sleepers with specific conditions |
Extra firm is available in two construction types. Each delivers maximum firmness in a different way.
An extra firm hybrid uses a heavy-gauge coil support system with a very thin, dense comfort layer. This construction prevents bottoming out under heavier body weights while maintaining the surface firmness that stomach sleepers and therapeutic users require. The coil system also provides strong edge support and better airflow than foam-only options.
Extra Firm Innerspring MattressesClassic coil construction with near-zero comfort layer — the firmest sleeping surface availableExtra firm innerspring mattresses offer a predictably flat, rigid sleeping surface with maximum pushback and minimal contouring. Built on traditional coil systems with little to no padding, they are the closest option to floor sleeping while still providing a supported foundation. Preferred by those who require a firm, flat surface for specific back conditions or therapeutic reasons.
We carry extra firm mattresses from select brands known for their maximum-support offerings.
We deliver to your room, unbox the mattress, set it up on your frame, and remove your old mattress. No additional cost. Scheduling available 7 days a week.
Every extra firm mattress comes with a 120-night comfort trial. Sleep on it for at least 30 nights, then decide. Not right? Free exchange or return — no restocking fee.
No interest for 12 months on approved credit. Split any extra firm mattress into monthly payments starting from $18/month on qualifying purchases.
Every extra firm mattress we sell online is available to try in person. Compare extra firm vs firm side by side at any of our Los Angeles showrooms.
Extra firm is a specialized choice. Call (800) 218-3578 or visit any showroom. Our specialists can help confirm whether extra firm is the right call for your sleep position and body weight.
What separates extra firm from firm, who it is for, and when it is the right choice.
A firm mattress rates 7–8 on a 10-point firmness scale. It provides solid support with minimal sinkage but still includes a measurable comfort layer that provides some cushioning. An extra firm mattress rates 9–10 and has little to no comfort layer — you are sleeping directly on a rigid support system with almost no give. Practically: a firm mattress still has some contouring and softness at the surface; an extra firm mattress feels nearly flat and rigid. Most people who say they want "extra firm" are actually well-served by a 7–8 firm. True extra firm (9–10) is appropriate only for dedicated stomach sleepers, very heavy individuals, or those with specific therapeutic requirements.
Extra firm mattresses are appropriate for a narrow but specific group: dedicated stomach sleepers who require maximum hip support to prevent lumbar hyperextension; very heavy sleepers (250+ lbs) who find firm mattresses compress to a medium feel under their weight; individuals with specific spinal conditions where a maximally firm surface has been recommended by a healthcare provider; and those transitioning from floor sleeping who need a firm, flat surface. For most back sleepers, a 7–8 firm is sufficient — extra firm is not necessary and can create discomfort for back and side sleepers who do not need it.
Extra firm is beneficial for back pain only in specific circumstances. For stomach sleepers, extra firm prevents the hip sinkage that causes lumbar hyperextension — a genuine source of back pain. For some very heavy back sleepers where firm mattresses still compress too much, extra firm may help maintain spinal alignment. However, extra firm is not a universal back pain remedy. For most back pain sufferers who sleep on their back, a firm (7–8) or medium-firm is more appropriate. For side sleepers with back pain, extra firm is typically the wrong choice — the rigid surface creates pressure at the hips and shoulders that can worsen pain. If you have back pain, consult with our specialists or your healthcare provider before selecting a firmness level.
Yes — for sleepers in the 250+ lb range, an extra firm mattress often delivers what a firm mattress cannot. At higher body weights, the compression force on a mattress is significantly greater. A mattress that rates firm (7–8) may compress to a medium feel for a 280-lb sleeper, while an extra firm (9–10) provides the actual resistance needed to maintain proper support and spinal alignment. Extra firm hybrids are particularly well-suited for heavier sleepers — the coil base prevents bottoming out, while the near-zero comfort layer maintains surface firmness under load.
Extra firm is a specific firmness that many customers have never tried before purchasing. We strongly recommend lying on it in person. Visit any of our 5 Los Angeles showrooms — no appointment needed.
Mon–Sat 10am–8pm
Sun 11am–7pm
Serving the Greater LA area
Every extra firm mattress backed by a 120-night sleep trial and free returns.