King
$58999
$1,99999
71% OFF
Medium Comfort, best for
Side,Back,Stomach Sleepers
Pain
Toss and Turn
6 Sizes
King Size Mattresses
285
results
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King
Only at Mattress Firm
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Best Seller
72 Hour Sale
King
$54999
$1,49999
63% OFF
Medium Comfort, best for
Back, Side and Stomach Sleepers
Pain
Toss and Turn
6 Sizes
Best Seller
Limited Time Deal
King
$60199
$1,49999
60% OFF
Ultra Plush Comfort, best for
Side Sleepers
Toss and Turn
Bed Partner
6 Sizes
Best Seller
Limited Time Deal
King
$65199
$1,49999
57% OFF
Medium Comfort, best for
Back, Side and Stomach Sleepers
Toss and Turn
Pain
7 Sizes
Best Seller
72 Hour Sale
King
$36999
$1,34999
73% OFF
Firm Comfort, best for
Back and Stomach Sleepers
Pain
Bed Partner
6 Sizes
Best Seller
72 Hour Sale
King
$53199
$1,89999
72% OFF
Plush Comfort, best for
Side Sleepers
Pain
Bed Partner
6 Sizes
14 of 285 results
King Size Mattresses
Providing the most room of any bed, couples find they have more space to accommodate their different sleep positions (and their pet!).
Measuring 76" wide and 80" long, a king size mattress provides plenty of space for a couple to sleep comfortably. Not every bedroom can fit a king mattress, so be sure to measure that the king mattress size is not too big for your sleeping space before getting your heart set on one of the many king bed mattress options available. Simmons was the first company to market the king mattress size.