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Medium Firm King Size Mattresses

Mattresses by size

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  1. Single.

    Single

  2. Small double.

    Small double

  3. Double.

    Double

  4. Kingsize.

    Kingsize

  5. Superking.

    Superking

  6. Kids mattresses.

    Kids mattresses

63 products
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Emma Original Lite Hybrid Mattress - Kingsize
Rating 4.5 out of 5, from 666 reviews
From
£355.00
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Silentnight Memory Cool 1000 Pkt Mattress - Kingsize
Rating 4.8 out of 5, from 28 reviews
From
£649.00
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Habitat Elite Memory Foam Kingsize Mattress
Rating 4.6 out of 5, from 597 reviews
From
£310.00
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Silentnight Travis Miracoil Double Sided Mattress - Kingsize
Rating 4.6 out of 5, from 3518 reviews
From
£275.00
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Argos pay. Flexible ways to pay for the things you need.

34.9% APR Representative (variable)

Subject to status. 18+. UK only. Terms apply. NewDay Ltd is the lender, Argos Limited is the credit broker.

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Silentnight Middleton 800 Pocket Memory Mattress - Kingsize
Rating 4.7 out of 5, from 1666 reviews
From
£389.00
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Silentnight 2800 Pocket Natural Mattress - King
Rating 4.8 out of 5, from 59 reviews
From
£699.00
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Emma Original Pro Hybrid Mattress - Kingsize
Rating 4.5 out of 5, from 374 reviews
From
£735.00
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Jay-Be Truecore Firm Hybrid 2200 Pocket Mattress - Kingsize
Rating 4.2 out of 5, from 50 reviews
From
£405.00
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Silentnight Studio Eco 1000 Pocket Mattress - King
Rating 4.6 out of 5, from 40 reviews
From
£475.00
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Silentnight Hush Memory Foam Mattress - Kingsize
Rating 4.1 out of 5, from 13 reviews
From
£249.00
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Silentnight Align 1400 Orthopaedic Mattress - Kingsize
Rating 5.0 out of 5, from 7 reviews
From
£839.00
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Aspire 1000 Pocket Damask Mattress - Kingsize
Rating 4.6 out of 5, from 31 reviews
From
£390.00
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Silentnight Ashford 1400 Pocket Memory Mattress - Kingsize
Rating 4.7 out of 5, from 296 reviews
From
£550.00
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Emma Original Hybrid Mattress - Kingsize
Rating 4.6 out of 5, from 670 reviews
From
£595.00
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Argos Home Elmdon Sprung Memory Rolled Kingsize Mattress
Rating 4.2 out of 5, from 1460 reviews
From
£235.00
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Silentnight Dewsbury 2800 Pocket Memory Mattress - Kingsize
Rating 4.8 out of 5, from 302 reviews
From
£805.00
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Silentnight Miracoil Travis Memory Foam Kingsize Mattress
Rating 4.7 out of 5, from 328 reviews
From
£489.00
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Argos Home Hybrid 900 Mattress - Kingsize
Rating 4.7 out of 5, from 31 reviews
From
£270.00
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Silentnight Eco Mirapocket 1200 Kingsize Mattress
Rating 4.8 out of 5, from 38 reviews
From
£545.00
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Argos Home Hybrid 2400 Pocket Kingsize Mattress
Rating 4.6 out of 5, from 288 reviews
From
£385.00
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Silentnight Eco Comfort Breathe Mattress -Kingsize
Rating 4.8 out of 5, from 49 reviews
From
£805.00
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Argos Home Salisbury 1000 Pocket Natural Mattress - Kingsize
Rating 4.5 out of 5, from 165 reviews
From
£350.00
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Argos Home Salisbury 1000 Pocket Memory Mattress - Kingsize
Rating 4.5 out of 5, from 165 reviews
From
£395.00
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Silentnight Breathe Plus Gel Foam Mattress - Kingsize
Rating 3.8 out of 5, from 4 reviews
From
£349.00
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Silentnight Breathe Gel Foam Mattress - Kingsize
Rating 4.6 out of 5, from 7 reviews
From
£289.00
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Sealy Posturepedic Elevate MemorySense Medium Firm Mattress - Kingsize
From
£1319.00
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Jay-Be Ryze Memory e-Fibre Mattress - Kingsize
Rating 4.1 out of 5, from 9 reviews
From
£349.00
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Silentnight Ultragel 1000 Pkt Sprung Mattress - Kingsize
Rating 5.0 out of 5, from 8 reviews
From
£689.00
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Silentnight Memory 2000 Pocket Pillowtop Mattress -Kingsize
Rating 4.8 out of 5, from 6 reviews
From
£709.00
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Aspire Cashmere 1000 Pocket Spring Mattress - Kingsize
Rating 4.3 out of 5, from 23 reviews
From
£425.00
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Simba Hybrid Mattress - Kingsize
Rating 4.8 out of 5, from 5032 reviews
From
£920.00
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Panda Hybrid Bamboo Mattress Pro - Kingsize
Rating 4.9 out of 5, from 108 reviews
From
£1390.00
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Aspire 7000 Pocket Mattress - Kingsize
Rating 4.8 out of 5, from 18 reviews
From
£1020.00
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Aspire 2000 Pocket Natural Mattress - Kingsize
Rating 4.3 out of 5, from 14 reviews
From
£550.00
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Millbrook Tranquil 3000 Pocket Mattress - Kingsize
Rating 4.8 out of 5, from 5 reviews
From
£735.00
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Millbrook Evolution 2000 Pocket Mattress - Kingsize
Rating 4.7 out of 5, from 3 reviews
From
£669.00
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Argos Home Winslow 600 Pocket Kingsize Mattress
Rating 4.4 out of 5, from 97 reviews
From
£235.00
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Sleepeezee Ortho Foundation 800 Pocket Mattress - Kingsize
Rating 5.0 out of 5, from 2 reviews
From
£580.00
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Sleepeezee Cool Ease 800 Pocket Mattress - Kingsize
Rating 4.8 out of 5, from 20 reviews
From
£630.00
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Silentnight Knightly 2000 Pocket Luxury Mattress - Kingsize
Rating 4.7 out of 5, from 174 reviews
From
£785.00
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Argos Home Carlton 800 Pocket King Mattress
Rating 4.5 out of 5, from 260 reviews
From
£275.00
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Dormeo Antigua Hybrid Mattress - Kingsize
Rating 4.7 out of 5, from 212 reviews
From
£350.00
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Habitat Aleta Natural 2000 Pkt Pillowtop Mattress - Kingsize
Rating 4.5 out of 5, from 6 reviews
From
£675.00
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Habitat Aleta Natural 2000 Pkt Comfort Mattress - Kingsize
Rating 3.5 out of 5, from 2 reviews
From
£575.00
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Jay-Be Benchmark S1 Comfort Eco Friendly King Mattress
Rating 4.4 out of 5, from 421 reviews
From
£225.00
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Habitat Ari Natural 1000 Pkt Pillowtop Mattress - Kingsize
Rating 4.8 out of 5, from 22 reviews
From
£485.00
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Dormeo Octasmart Hybrid Plus Mattress - Kingsize
Rating 4.6 out of 5, from 252 reviews
From
£739.00
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Silentnight Just Sleep Snug Memory Foam Mattress - Kingsize
Rating 4.5 out of 5, from 38 reviews
From
£589.00
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Silentnight Just Sleep Breathe Rolled Eco Mattress -Kingsize
Rating 4.4 out of 5, from 57 reviews
From
£530.00
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Silentnight Just Sleep Relax Memory Foam Mattress - Kingsize
Rating 4.3 out of 5, from 111 reviews
From
£355.00
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Dormeo Octasmart Hybrid Mattress - Kingsize
Rating 4.6 out of 5, from 462 reviews
From
£700.00
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Silentnight Miracoil Eco Pillowtop Mattress - Kingsize
Rating 4.5 out of 5, from 101 reviews
From
£360.00
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Silentnight 1400 Pocket Natural Mattress - King
Rating 4.5 out of 5, from 12 reviews
From
£635.00
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Silentnight Lift Replenish 2000 Firm Mattress - Kingsize
Rating 4.3 out of 5, from 6 reviews
From
£829.00
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Dormeo Comfort Memory Foam Mattress - Kingsize
Rating 4.5 out of 5, from 97 reviews
From
£310.00
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Sealy Thames Ortho Memory Pillowtop Kingsize Mattress
Rating 5.0 out of 5, from 2 reviews
From
£850.00
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Sealy Kingham Ortho Memory Firm Kingsize Mattress
Rating 5.0 out of 5, from 2 reviews
From
£600.00
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Sealy Crosswall Ortho Deluxe Kingsize Mattress
Rating 4.5 out of 5, from 8 reviews
From
£590.00
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3 Colours available
Silentnight Marlow Memory Mattress & Divan Set
From
£740.00
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Sealy Advantage Deluxe Sense Medium Firm Mattress -Kingsize
From
£989.00
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