King Size Mattresses
King size mattresses are perfect for couples or taller sleepers who need extra room. Choose from supportive hybrids to luxury natural fillings. Shop top UK brands like Silentnight, Sleepeezee, Hypnos, and Sealy.
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Mlily Bamboo+ Superb Memory 2500 Pocket Mattress
Was £519.95
RRP £1,020.00
Emma Hybrid Premium Mattress
Was £528.99
RRP £593.00
Silentnight Athens 1400 Mirapocket Ortho Mattress
Was £499.95
RRP £602.00
Simba Essential Comfort Hybrid 1000 Pocket Mattress
Was £709.95
RRP £749.00
Silentnight Rio Miracoil Cushion Top Mattress
Was £419.95
RRP £498.00
Hypnos Hemsworth Deluxe Mattress
Was £704.95
RRP £1,150.00
Millbrook Wool Luxury 4000 Pocket Mattress
Was £934.95
RRP £1,501.27
Sealy Waltham Latex Advantage Mattress
Was £649.95
RRP £949.00
SleepSoul Heaven 1000 Pocket Gel Mattress
Was £324.95
RRP £545.99
Emma Hybrid Thermosync Mattress
Was £688.74
RRP £1,399.00
Harrison Spinks Luxury Essential 750 Pocket Mattress
Was £644.95
RRP £859.00
Simba Earth Escape 4800 Wool Mattress
Was £1,684.95
RRP £1,799.00
Hypnos Marlow Ortho Deluxe Mattress
Was £1,234.95
RRP £2,159.00
Silentnight Seoul Miracoil Memory Mattress
Was £444.95
RRP £542.00
Sealy Mellbreak Ortho Plus Mattress
Was £464.95
RRP £699.00
Jay-Be 1000 e-Pocket TRUECORE Eco-Friendly Mattress
Was £364.95
RRP £500.00
SleepSoul Bliss 800 Pocket Memory Pillow Top Mattress
Was £404.95
RRP £659.99
Relyon Isabelle 2000 Pocket Mattress
Was £734.95
RRP £1,078.00
Memory Zone 3000 Pocket Mattress
Was £664.95
RRP £929.00
Luna Memory 2500 Pocket Hybrid Mattress
Was £559.95
RRP £990.00
How much should I spend on my king size mattress?
King size mattress prices vary by brand and the materials used, but rest assured, we have options for every budget:
- Budget: from £200 - great value blended with everyday comfort
- Mid-range: £400-£600 - enhanced support and extra features for blissful sleep
- Premium: £600-£3,300+ - luxury comfort from leading brands with handcrafted quality
At Mattress Online, we’re dedicated to bringing you the best value at every price point.
Why buy a king size mattress from Mattress Online?
We’ve been helping Mattress Online customers find the right king size mattress for over 20 years.
- Over 40 trusted brands - Choose from Silentnight, TEMPUR, Emma, Sealy and more, all in stock and ready to ship
- Over 20 years of sleep expertise - We’ve delivered over 800,000 mattresses to across the UK
- Rated 'Excellent' on Trustpilot - Shop with confidence backed by over 66,000 verified customer reviews
- Free next day delivery - Order by 4pm and your king size mattress can be with you as soon as tomorrow, or choose a day that works for you
- 60-Night Comfort Trial - A mattress is an investment. Try it out, and if it doesn’t work out, we’ll work with you to find one that does
Advice and buying guides
See what our customers say about us
Why buy from Mattress Online?
Free delivery to most locations
Free next working day delivery on most of our mattresses and beds, or upgrade to weekend delivery.
Free 60-night mattress comfort trial
Test your mattress for 60 nights and if you don't like it, simply swap it.
Old mattress disposal
We can collect and recycle your mattress - saving it from landfill.
Sales Enquiries
Mon-Sat: 9:30am - 5:30pm
Sunday: 10am - 4pm
Customer Service
Mon-Sat: 9:30am - 5:30pm
Sunday: Closed
customerservice@mattressonline.co.uk
