Luxury King Size Firm Mattresses

Explore Luxury King Size Firm Mattresses to find a spacious sleep surface with a supportive feel for your bedroom. Compare styles, comfort levels and price points to discover a king mattress that fits your space, preferences and sleep routine.

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Stearns & Foster Reserve Duet 17" Firm Euro Pillow Top Mattress

Starting at

$6499⁰⁰

$7199⁰⁰

$700 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

Receive $300 Instant Gift⁴ with purchase.

Beautyrest Black Series Three 16.5" Firm Pillow Top Mattress

297

Starting at

$4599⁰⁰

$5199⁰⁰

$600 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

$300 ⁶ adjustable base instant gift with purchase.

Kingsdown Crown Imperial 16" Firm Euro Top Mattress

125

Starting at

$5299⁰⁰

$6899⁰⁰

$1600 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Beautyrest Black Series Three 15" Firm Mattress

2224

Starting at

$4199⁰⁰

$4799⁰⁰

$600 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

$300 ⁶ adjustable base instant gift with purchase.

Tempur-Pedic TEMPUR-LuxeAdapt 2.0 13" Firm Mattress

1449

Starting at

$5099⁰⁰

$5599⁰⁰

$500 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Temperature
Allergies
Bed Partner
Toss and Turn

Receive $300 Instant Gift⁴ with purchase + Calm app 3-month free trial

Purple RestorePremier 13" Firm Hybrid Mattress

1590

Starting at

$4400⁰⁰

$5199⁰⁰

$799 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Allergies
Bed Partner
Toss and Turn
Temperature

Tempur-Pedic TEMPUR-LuxeBreeze Firm 13" Mattress

1546

Starting at

$6099⁰⁰

$6599⁰⁰

$500 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

Receive $300 Instant Gift⁴ with purchase + Calm app 3-month free trial

Stearns & Foster Reserve 17" Firm Euro Pillow Top Mattress

674

Starting at

$5499⁰⁰

$6199⁰⁰

$700 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

Receive $300 Instant Gift⁴ with purchase.

Beautyrest Black Series Three 14.25" Extra Firm Mattress

284

Starting at

$4199⁰⁰

$4799⁰⁰

$600 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

$300 ⁶ adjustable base instant gift with purchase.

Beautyrest Black Series Four 17.5" Firm Summit Pillow Top Mattress

231

Starting at

$5899⁰⁰

$6599⁰⁰

$700 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

$300 ⁶ adjustable base instant gift with purchase.

Beautyrest Black Hybrid Series Three 14.5" Firm Mattress

102

Starting at

$4099⁰⁰

$4699⁰⁰

$600 OFF

Firm Comfort,

Pain
Bed Partner
Temperature
Toss and Turn

$300 ⁶ adjustable base instant gift with purchase.

Kingsdown Crown Imperial 15" Firm Mattress

Starting at

$4599⁰⁰

$5999⁰⁰

$1400 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Beautyrest Black Hybrid Series Four 16" Firm Apex Top Mattress

Starting at

$5899⁰⁰

$6599⁰⁰

$700 OFF

Firm Comfort,

Pain
Bed Partner
Temperature
Toss and Turn

$300 ⁶ adjustable base instant gift with purchase.

Purple Rejuvenate Royale Duke Mattress

Starting at

$6500⁰⁰

$8099⁰⁰

$1599 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

$300 adjustable base instant gift with purchase.

Kingsdown Wesley 15.5" Firm Mattress

Starting at

$4199⁰⁰

$4799⁰⁰

$600 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

$300 ⁶ adjustable base instant gift with purchase.

A luxury king size firm mattress combines generous sleeping space with a supportive, refined sleep surface designed for sleepers who prefer a solid feel. Measuring approximately 76 inches wide by 80 inches long, a king mattress gives couples room to stretch out while helping reduce motion transfer with the right construction. Luxury firm mattresses may feature individually wrapped coils, reinforced edges, high-density foam, natural fibers or TEMPUR-Material™, creating a balanced blend of support, comfort and durability. For back and stomach sleepers, a firm king mattress can provide the stable feel many prefer, while zoned support and pressure-relieving comfort layers help promote a more comfortable sleep posture without making the surface feel overly hard. Choosing the best luxury king size firm mattress starts with comparing mattress materials, firmness levels and support features. Hybrid king mattresses pair a responsive innerspring system with cushioning foam or latex, while all-foam designs offer a quieter feel and can contour more closely to the body. Look for breathable covers, cooling materials and reinforced edges if you share the bed or want more usable sleeping space. A luxury king mattress can also be paired with an adjustable base for personalized positioning, easier entry and exit, and customized comfort. Mattress Firm offers a wide selection of firm king size mattresses from trusted brands, along with expert guidance to help you find a high-quality mattress that fits your sleep style, bedroom and budget.

What makes a luxury firm mattress feel different? + -

Luxury firm mattresses typically combine a supportive, stable feel with comfort layers designed to provide gentle cushioning. Premium materials and detailed construction can contribute to a more refined sleep surface.

What materials are commonly used in luxury firm mattresses? + -

Common materials include high-density foams, gel-infused foam, latex, individually wrapped coils and quilted fabric covers. The specific combination affects the mattress's feel, support and surface comfort.

Who may prefer a luxury firm mattress? + -

People who enjoy a more supportive sleep surface and less sink may prefer a luxury firm mattress. It can also suit sleepers who want cushioning without a deeply plush feel.

How can I compare luxury firm mattresses? + -

Compare their comfort layers, support systems, materials, edge design and cover fabrics. Pay attention to how each construction balances cushioning and stability to find a feel that matches your preferences.

How should I care for a luxury firm mattress? + -

Use a compatible foundation, protect the surface with a breathable mattress protector and follow the care instructions provided with the mattress. Rotating it according to the manufacturer's guidance may also help promote even wear.