Extra Firm Mattresses

Why choose an extra firm mattress?

Extra firm mattresses are ideal if you have a larger build or prefer a solid sleep surface. They help maintain natural spinal alignment - especially if you sleep on your back – for a healthier night’s rest.

Need help choosing between mattress firmnesses? Read our expert firmness scale guide.

Is an extra firm mattress better for your back?

Yes, extra firm mattresses can support better posture by preventing your body from sinking too deeply. However, they’re best suited to certain body types, such as heavier sleepers or those who prefer a very firm mattress feel.

This can help reduce back pain and improve spinal alignment, especially for heavier sleepers and back sleepers.

What extra firm mattress sizes are there?

Our firmest mattresses are available in all standard sizes:

• Small single - 75cm x 190cm
• Single - 90cm x 190cm
• Small double - 120cm x 190cm
• Double - 135cm x 190cm
• King size - 150cm x 200cm
• Superking - 180cm x 200cm
• Superking zip and link - 180cm x 200cm

What is the firmest mattress you can buy?

These are our firmest mattresses, loved by customers for their solid support:

• Rock Hard Super Firm Mattress
• Rock Hard Mega Firm Mattress
• Silentnight Ortho Dream Star Miracoil Mattress

All rated highly by our MattressOnline customers.

How much does an extra firm mattress cost?

We stock extra firm mattresses from top brands for every budget:

• Budget: from £180 - cheap extra firm mattresses that deliver great value and everyday comfort
• Mid-range: £200-£500 - enhanced features for blissful sleep
• Premium: £600+ - luxury comfort from leading brands with handcrafted quality

All of our very firm mattresses are available with free next day delivery across most of the UK.