Firm Mattresses

What are the benefits of a firm mattress?

23% of UK poor sleepers say they can't get comfortable in bed. Firm support from your mattress addresses this in several ways:

• Spinal alignment: a firm mattress keeps your spine in a neutral position throughout the night, which is particularly important for back and stomach sleepers. When a mattress is too soft, the hips sink lower than the shoulders on your back, or the stomach drops below the hips when you're face down, both cause the spine to curve and can lead to morning stiffness or lower back pain.
• Pressure relief: by distributing your weight more evenly across the surface rather than allowing it to concentrate at the hips and shoulders, a firm mattress reduces pressure on joints.
• Motion isolation: the denser, less compressible feel of a firm mattress means less movement transfer across the surface, useful if you share a bed and one of you moves in the night.
• Longevity: firm mattresses tend to hold their structure for longer than softer options. A well-made firm mattress should last around 8–10 years before it begins to lose its support.

What sleeping position are firm mattresses best for?

Firm mattresses are great for a wide range of sleeping positions, including back, stomach and combination sleepers. This is because a firm mattress supports and maintains proper spinal alignment, preventing back pain and the lower back from arching. They also ensure that your body remains properly supported if you change positions as you sleep.

However, if you are a side sleeper, you may find that a firm mattress is too hard and doesn’t offer as much cushioning as you need. To help you pick the right one for you, browse our mattresses by sleeping position or read our guide to find the best sleeping position for you.

Is a firm mattress right for me?

The firmness level that suits you depends on your sleeping position, body weight, and any aches or pains you have.

Firm is likely right for you if:

• you sleep on your back or stomach
• you're a heavier sleeper (roughly 16 stone / 100kg or above) and find softer mattresses compress too much
• you sleep with a partner and want minimal disturbance when they move
• your current mattress has started to dip or feel soft and your back is suffering for it.

Firm may not suit you if: you sleep mainly on your side, as the firmer surface won't allow enough give at the shoulder and hip; you are a lighter sleeper who needs more contouring to feel comfortable.

Not sure where you sit? Medium mattresses offer a balance of support and softness. Or try our Sleepmatch service to find your ideal firmness match.

Are firm mattresses good for those with back pain?

Yes, a firm mattress can make a real difference if back pain is keeping you up at night. By keeping your spine in a neutral position, a firm surface stops your lower back from sinking and straining through the night. The NHS recommends medium-to-firm mattresses for most people with back pain, as they provide the support needed to keep the spine aligned without placing excessive pressure on any one area. A mattress that is too soft causes the spine to sag; one that is too hard creates pressure points at the hips and shoulders. A firm or orthopaedic mattress falls within the range recommended by most sleep health guidance.

That said, it is not a one-size-fits-all situation or a cure for ongoing back pain with an underlying cause. The right firmness for you depends on your sleeping position, build, and the type of back pain you're dealing with. For a closer look at how your mattress choice affects your back health, see our mattress for back pain guide.

What is the difference between a firm and an extra firm mattress?

A firm mattress gives strong support with a noticeably solid feel underfoot. It resists compression more than a medium mattress but still has some give, enough to relieve pressure at the hips and shoulders for back and stomach sleepers. An extra firm mattress goes a step further, it offers the highest level of support with very little surface compression. Extra firm is often recommended for very heavy sleepers, those with specific orthopaedic needs, or people who find a standard firm mattress still feels too yielding. For most sleepers who want firm support, a firm mattress is the right starting point. Extra firm is a specialist option. If you're unsure, try firm first. Browse our extra firm mattresses if you need that additional level of support.

What size firm mattresses are available?

We stock firm mattresses in every standard UK size, from euro small single, cot, small single, single to emperor. The most common sizes are:

• Small double firm mattresses (4ft / 120cm x 190cm): also known as a queen size. Good for a solo sleeper who wants more room, or a couple in a smaller bedroom.
• Double firm mattresses (4ft 6in / 135cm x 190cm): the most popular size for couples. Comfortably wide enough for two people on a firm mattress.
• King size firm mattresses (5ft / 150cm x 200cm): the step up for couples who want more room, both wider and longer than a double.
• Super king firm mattresses (6ft / 180cm x 200cm): the most generous standard UK size. A firm super king is particularly well-suited to heavier couples.
• Emperor firm mattresses (6ft 6in / 200cm x 200cm): available on selected ranges, these luxurious options offer more than enough space.

See our mattress size guide for full dimensions and room planning advice.

What firm mattress fillings can I choose from?

Our firm mattresses come with a variety of fillings, such as:

• Pocket spring firm mattresses: individually wrapped springs provide targeted support and reduce motion transfer. One of the most popular filling types for back and stomach sleepers. Springs move independently, so the mattress responds to your body's specific weight distribution rather than creating a single uniform surface.
• Memory foam firm mattresses contour to your body shape to relieve pressure while maintaining firm underlying support. Particularly good for back pain sufferers. Available in a range of densities, firmer memory foam gives more structured support without sacrificing the contouring benefit.
• Latex and Gel firm mattresses: natural latex is highly responsive and breathable, making it a good option for sleepers who run warm. Geltex is a gel-infused foam that combines pressure relief with temperature regulation. Both are often combined with a spring base.
• Combination firm mattresses: a mix of springs and foam offering a balance between firm support and comfort. Ideal for sleepers who switch positions through the night.
• Natural filling firm mattresses: materials such as wool, cotton and cashmere are used in higher-end firm mattresses. They regulate temperature naturally and are a good choice if you prefer sustainable materials. Brands such as Flaxby offer handmade firm mattresses using natural fillings.
• Traditional spring firm mattresses offer firm spring support at a more affordable price. They’re best suited to back and stomach sleepers who want straightforward, no-fuss support.

Not sure which filling suits you? Compare our mattress types to learn more.

What brands of firm mattresses are available?

There are several trusted mattress brands that offer firm mattresses, each with unique features. Choose from brands like Silentnight, Sealy, TEMPUR, TheraPur, and Sleepeezee for firm mattresses with advanced support and durability. You’ll get the best spinal support and contouring comfort with spring and foam fillings, plus pressure-relief benefits. For a touch of luxury made from natural materials, choose brands such as Flaxby for eco-friendly options or Relyon for handmade firm mattresses.

For brands that focus on comfort and edge support, choose Hyde and Sleep for cooling technology and Dreams Workshop or Dream Team for spring and pocket systems with advanced features. For growing bodies, Little Big Dreams specialises in offering firm support with natural materials, ensuring a safe sleeping environment.

What if my new mattress is causing back pain?

Some discomfort in the first few weeks is normal, as your body adjusts to your new sleep surface. Switching to something that provides better spinal support can feel strange or even uncomfortable at first as your muscles and posture adjust. This typically resolves within 4 to 8 weeks. If the discomfort improves during the day once you are up and about, that is a good sign your body is adjusting.

If it persists beyond eight weeks without improvement, or gets worse rather than better, that is when to get in touch with us. Our 100-night comfort guarantee is there for exactly this situation. Why not try before you buy at a store near you and feel our firm mattresses for yourself? Our friendly team will be on hand to help you find the right firm mattress for you!