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Deal of the day: Shop our best deals on top brands like Sealy^® & more

Firm King Mattresses

84

results

Firm

King

Black Hybrid Series One 12.5" Firm Mattress

Beautyrest Black Hybrid Series One 12.5" Firm Mattress

King

Firm Comfort, best for

Pain
Bed Partner
Temperature

6 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Black Hybrid Series Four 16" Firm Apex Top Mattress

Beautyrest Black Hybrid Series Four 16" Firm Apex Top Mattress

King

Firm Comfort, best for

Pain
Bed Partner
Temperature

6 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Best Seller

By Sealy® Slumber Firm Mattress

Sleepy's By Sealy® Slumber Firm Mattress

King

Firm Comfort, best for

Back and Stomach Sleepers
Bed Partner
Toss and Turn

6 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Black Hybrid Series Two 13.5" Firm Mattress

Beautyrest Black Hybrid Series Two 13.5" Firm Mattress

King

Firm Comfort, best for

Pain
Bed Partner
Temperature

6 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Best Seller

PressureSmart™ 2.0 Firm 11" Mattress

Beautyrest PressureSmart™ 2.0 Firm 11" Mattress

King

Firm Comfort, best for

Back and Stomach Sleepers
Pain
Temperature

8 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Having trouble deciding?

Perfect Sleeper® Nurture Night 12" Firm Mattress

Serta Perfect Sleeper® Nurture Night 12" Firm Mattress

King

Firm Comfort, best for

Back and Stomach Sleepers
Pain
Bed Partner

6 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Best Seller

Perfect Sleeper® Oasis Sleep 14.5" Firm Pillow Top Mattress

Serta Perfect Sleeper® Oasis Sleep 14.5" Firm Pillow Top Mattress

King

Firm Comfort, best for

Back and Stomach Sleepers
Pain
Bed Partner

6 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Posturepedic® Ashurst II 13" Firm Mattress

Sealy Posturepedic® Ashurst II 13" Firm Mattress

King

Firm Comfort, best for

Back Sleepers
Pain
Allergies

7 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Best Seller

PressureSmart™ 2.0 Hybrid Firm 13" Mattress

Beautyrest PressureSmart™ 2.0 Hybrid Firm 13" Mattress

King

Firm Comfort, best for

Back and Stomach Sleepers
Pain
Temperature

7 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Best Seller

Basic Innerspring Firm Mattress

Sleepy's Basic Innerspring Firm Mattress

King

Firm Comfort, best for

Back and Stomach Sleepers

5 Sizes

Delivery in6+ weeks

Best Seller

By Sealy® Spring Firm Mattress

Sleepy's By Sealy® Spring Firm Mattress

King

Firm Comfort, best for

Back and Stomach Sleepers
Pain
Bed Partner

6 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Green Tea 12” Cushioned Firm Memory Foam Mattress

Zinus Green Tea 12” Cushioned Firm Memory Foam Mattress

King

Firm Comfort, best for

Back and Stomach Sleepers
Pain
Temperature

5 Sizes

Delivery in6+ weeks

Best Seller

iSeries® 2.0 Hybrid 2000 12.5" Firm Mattress

Serta iSeries® 2.0 Hybrid 2000 12.5" Firm Mattress

King

Firm Comfort, best for

Back and Stomach Sleepers
Temperature
Bed Partner

5 Sizes

FREE ADJUSTABLE BASE³ up to $499 value with code ELEVATE (must add base to cart)

Delivery in6+ weeks

Green Tea 6” Cushioned Firm Memory Foam Mattress

Zinus Green Tea 6” Cushioned Firm Memory Foam Mattress

King

Firm Comfort, best for

Back and Stomach Sleepers
Pain
Temperature

6 Sizes

Delivery in6+ weeks

14 of 84 results

Firm King Mattresses

Stop searching for beds that are the wrong firmness for you. Get the most out of your new mattress purchase and consult a Sleep Expert for your ideal firmness.

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