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10 Best firm king size mattresses of 2026
Save up to 39% off
Best Choice1
Clicked 62 times in the last monthMLILYEGOHOME 14 Inch King Size Memory Foam Mattress for Back Pain, Cooling Copper Gel Bed in a Box, Foam Made in USA, CertiPUR-US Certified, Therapeutic Medium Firm, 76x80x14 Black
27% OffKey specs-
size:King
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construction:High density base foam
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fill material:Memory foam
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dimensions:80 x 76 x 14 inches
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top style:Cooper gel aerofuion
9.9Exceptional
Our Rating
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Value for Money2
BedStoryBedStory Extra Firm King Mattress 14 Inch, Hotel Collection Hybrid Mattresses with Zoned Lumbar Support, Extra Back & Hip Support, CertiPUR-US, Fiberglass-Free, 365-Night Trial
25% Off9.7Exceptional
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SLEEP100SLEEP100 King Mattress, 14 Inch 5-Zone Deep Sleep Firm Mattress with Extra Lumbar & Shoulder Support, Hotel Collection Hybrid Mattresses, Fiberglass Free & No Odor - 365 Nights Trial
9.6Exceptional
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4
UniPonUniPon Extra Firm King Size Mattress, 14 inch Hybrid Mattress with Extra Back and Lumbar Hip Support, Fiberglass Free, 365 Nights Trial & 10 Years Warranty
9.5Excellent
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5
NovillaNovilla King Size Mattress, 12 Inch Gel Memory Foam King Mattress for Cool Night & Pressure Relief, Medium Plush Feel with Motion Isolating, Bliss
23% Off Limited Time DealKey specs-
size:King
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construction:4-layer all-foam system
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fill material:Memory foam
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dimensions:80 x 76 x 12 inches
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top style:Gel-infused memory foam
9.4Excellent
Our Rating
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ZinusZinus 12 Inch King Green Tea Memory Foam Mattress [New Version], Fiberglass Free, Medium Firm Feel, Zoned Pressure Relief, Certified Safe Foams & Fabric, Mattress in A Box
28% Off Limited Time DealKey specs-
size:King
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construction:Zoned pressure relief
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fill material:Memory Foam
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dimensions:80 x 76 x 12 inches
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top style:N/A
9.3Excellent
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UniPonUniPon 14 inch Firm King Size Mattress, Hybrid Mattress with Extra Back and Lumbar Support, Fiberglass Free, 365 Nights Trial & 10 Years Warranty, Motion Isolation, Enhenced Edge Support
10% Off Limited Time Deal9.0Excellent
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VISCOFLEXVISCOFLEX Extra Firm King Mattress 14 Inch, Hybrid Mattress Extra Lumbar Support Pain Relief, No Sagging Bed Mattresses in a Box - 365-Night Trial, CertiPUR-US, Hotel Collection
8.8Very Good
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UniPonUniPon Firm King Size Mattress 14 inch, Deep Sleep Hybrid Mattress with Extra Back & Hip Support, Motion Isolation with Fiberglass-Free, CertiPUR-US Certified, 365-Night Trial
39% Off Limited Time Deal8.7Very Good
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10
FATHOMFATHOM Firm King Mattress 12 Inch Memory Foam Mattress King Size Bed in a Box for Back Pain Relief and Cool Sleep with Gel Foam and Removeable Fiberglass Free Cover, CertiPUR-US Certified
16% Off Limited Time Deal8.5Good
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