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King Size Mattresses

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Blackstone 12" Memory Foam Mattress and Platform Bed Set

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More Colors Available

Starting at
$639.99
Blackstone 12" Memory Foam Mattress and Platform Bed Set
Rated 4.5 out of 5 stars based on 8688 reviews.
(8688)

More Colors Available

Sleep Science 12” iFlip Sonoma King Dual Comfort Memory Foam Mattress

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$899.99
Sleep Science 12” iFlip Sonoma King Dual Comfort Memory Foam Mattress
Rated 4.3 out of 5 stars based on 780 reviews.
(780)
Thomasville Gel Rest 12" Memory Foam Mattress and Foundation Set

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$2,199.99
Thomasville Gel Rest 12" Memory Foam Mattress and Foundation Set
Rated 4 out of 5 stars based on 75 reviews.
(75)
Thomasville Gel Choice 12.5" Memory Foam Split King Mattress with Adjustable Base

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$4,399.99
Thomasville Gel Choice 12.5" Memory Foam Split King Mattress with Adjustable Base
Rated 4.1 out of 5 stars based on 148 reviews.
(148)
Blackstone 12" Memory Foam King Mattress

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$549.99
Blackstone 12" Memory Foam King Mattress
Rated 4.5 out of 5 stars based on 8271 reviews.
(8271)
Thomasville Precision Gel 14" Memory Foam Mattress

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Starting at
$2,099.99
Thomasville Precision Gel 14" Memory Foam Mattress
Rated 3.8 out of 5 stars based on 59 reviews.
(59)
Blackstone 10" Mattress and Grand Tufted Platform Bed Set

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Starting at
$699.99
Blackstone 10" Mattress and Grand Tufted Platform Bed Set
Rated 4.4 out of 5 stars based on 920 reviews.
(920)
Comfort Tech 10" Serene Firm King Mattress

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$499.99
Comfort Tech 10" Serene Firm King Mattress
Rated 4.3 out of 5 stars based on 1445 reviews.
(1445)
Blackstone Set-10” Memory Foam King Mattress and Platform Bed

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$899.99
Blackstone Set-10” Memory Foam King Mattress and Platform Bed
Rated 4.2 out of 5 stars based on 159 reviews.
(159)
Blackstone Elite 10" Gel Infused Memory Foam Mattress

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Starting at
$249.99
Blackstone Elite 10" Gel Infused Memory Foam Mattress
Rated 4.4 out of 5 stars based on 926 reviews.
(926)
Thomasville Precision Gel 14" Memory Foam Mattress and Foundation Set

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Starting at
$2,499.99
Thomasville Precision Gel 14" Memory Foam Mattress and Foundation Set
Rated 3.8 out of 5 stars based on 59 reviews.
(59)
Sleep Science 14" Copper Infused King Memory Foam Mattress - Firm

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$899.99
Sleep Science 14" Copper Infused King Memory Foam Mattress - Firm
Rated 4.3 out of 5 stars based on 598 reviews.
(598)
Blackstone Deluxe 12" Hybrid iCoil Spring and Memory Foam Mattress

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Starting at
$329.99
Blackstone Deluxe 12" Hybrid iCoil Spring and Memory Foam Mattress
Rated 4.3 out of 5 stars based on 662 reviews.
(662)
Comfort Tech Intuition 12" Memory Foam King Mattress

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$649.99
Comfort Tech Intuition 12" Memory Foam King Mattress
Rated 4.2 out of 5 stars based on 11 reviews.
(11)
Beautyrest 12" Silver Micro Diamond Memory Foam Mattress

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Starting at
$699.99
Beautyrest 12" Silver Micro Diamond Memory Foam Mattress
Rated 4.3 out of 5 stars based on 96 reviews.
(96)
Novaform 14" Comfort Grande Plus Memory Foam Mattress

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Starting at
$399.99
Novaform 14" Comfort Grande Plus Memory Foam Mattress
Rated 4.4 out of 5 stars based on 4097 reviews.
(4097)
Cocoon by Sealy 10" King Memory Foam Mattress

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$649.99
Cocoon by Sealy 10" King Memory Foam Mattress
Rated 4.4 out of 5 stars based on 802 reviews.
(802)
Sleep Science 13" Bamboo Cool Firm Mattress

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Starting at
$649.99
Sleep Science 13" Bamboo Cool Firm Mattress
Rated 4.6 out of 5 stars based on 36 reviews.
(36)
Sleep Science 13" Bamboo Cool Split King Mattress with Q Plus Adjustable Base

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$2,599.99
Sleep Science 13" Bamboo Cool Split King Mattress with Q Plus Adjustable Base
Rated 4.4 out of 5 stars based on 83 reviews.
(83)
Sensalux 12" Medium Firm King Hybrid Gel and Memory Foam Mattress

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$599.99
Sensalux 12" Medium Firm King Hybrid Gel and Memory Foam Mattress
Rated 4.2 out of 5 stars based on 333 reviews.
(333)
Drexel Heritage 15" Royale Hybrid and Gel Memory Foam Mattress with Adjustable Base

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Starting at
$3,999.99
Drexel Heritage 15" Royale Hybrid and Gel Memory Foam Mattress with Adjustable Base
Rated 3.3 out of 5 stars based on 24 reviews.
(24)
Sleep Science 10" iFlip Solano Split King Memory Foam Mattress with QPlus Adjustable Base

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$2,499.99
Sleep Science 10" iFlip Solano Split King Memory Foam Mattress with QPlus Adjustable Base
Rated 4.3 out of 5 stars based on 235 reviews.
(235)
Sleep Science 9" Natural Latex Split King Mattress with Adjustable Power Base

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$4,499.99
Sleep Science 9" Natural Latex Split King Mattress with Adjustable Power Base
Rated 4.2 out of 5 stars based on 285 reviews.
(285)
Sleep Science Ara 13" Split King Memory Foam Mattress with QPlus Adjustable Base

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$2,999.99
Sleep Science Ara 13" Split King Memory Foam Mattress with QPlus Adjustable Base
Rated 4.3 out of 5 stars based on 1020 reviews.
(1020)
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King Bedroom Sets

Bed Frames

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Sheets

Considerably roomier than the queen- or full-sized mattresses, the ever popular King mattress allows ample of room to really stretch out and relax. Although shorter than the California king, the standard king mattress is often wider, making it a great option for many people. Browse Costco’s expansive selection of king mattresses, which can be conveniently filtered by brand, firmness, and composition, Whether you’re looking for a luxuriously plush pillow top, body hugging ultra-firm support, or responsive multi-layer memory foam, you’ll find what you’re looking for at Costco. A great night’s sleep awaits!