Firm Height 84 Mattresses

Explore Firm Height 84 Mattresses at Mattress Firm to find a selection of mattresses in a firm feel and 84-inch size. Compare available options by comfort preference, size and budget to find the right fit for your bedroom and sleep routine.

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Beautyrest Silver BRS900 11.75" Extra Firm Mattress

3296

Starting at

$1699⁹⁹

Extra Firm Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Serta Perfect Sleeper Charlotte 2.0 Medium Euro Top Mattress

2615

Starting at

$1499⁹⁹

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Sleepy's Rest Firm 2.0 Innerspring Mattress

7001

Starting at

$449⁹⁹

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

Serta Perfect Sleeper Sleep Excellence Medium PillowTop Mattress

1433

Starting at

$1999⁹⁹

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Tempur-Pedic TEMPUR-Adapt 11" Medium Previous Generation Mattress

3631

Starting at

$1189⁷⁷

$1699⁰⁰

$509 OFF

Medium Comfort, best for

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

Beautyrest BR800 11.25" Firm Mattress

2233

Starting at

$1299⁹⁹

Firm Comfort, best for

Back, Stomach Sleepers
Toss and Turn
Pain
Bed Partner
Temperature

FREE ADJUSTABLE BASE ³ with code ELEVATE

Beautyrest BR800 13.5" Medium Pillow Top Mattress

1863

Starting at

$1499⁹⁹

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Beautyrest Silver BRS900 11.75" Medium Firm Mattress

1745

Starting at

$1099⁹⁹

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Beautyrest BR800 12" Plush Euro Top Mattress

735

Starting at

$1399⁹⁹

Plush Comfort, best for

Side Sleepers
Toss and Turn
Pain
Bed Partner
Temperature

FREE ADJUSTABLE BASE ³ with code ELEVATE

Serta Perfect Sleeper Nurture Night 12" Firm Mattress

1186

Starting at

$999⁰⁰

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Beautyrest Silver BRS900 12" Plush Mattress

1140

Starting at

$1699⁹⁹

Plush Comfort, best for

Side Sleepers
Temperature
Pain
Bed Partner
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Serta Perfect Sleeper Nurture Night 14.5" Pillow Top Mattress

1130

Starting at

$1249⁰⁰

Plush Comfort, best for

Side Sleepers
Pain
Temperature
Bed Partner
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Serta Perfect Sleeper Nurture Night 13.5" Medium Mattress

1020

Starting at

$1099⁰⁰

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Serta Perfect Sleeper Oasis Sleep 12" Extra Firm Mattress

905

Starting at

$1399⁰⁰

Extra Firm Comfort, best for

Back, Stomach Sleepers
Pain
Temperature
Bed Partner
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Serta Perfect Sleeper Nurture Night 13.5" Plush Mattress

916

Starting at

$1099⁰⁰

Plush Comfort, best for

Side Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Tempur-Pedic TEMPUR-ProAdapt 2.0 12" Firm Mattress

4992

Starting at

$2599⁰⁰

$2999⁰⁰

$400 OFF

Firm Comfort, best for

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

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

Tempur-Pedic TEMPUR-ProAdapt 2.0 12" Medium Mattress

3858

Starting at

$2599⁰⁰

$2999⁰⁰

$400 OFF

Medium Comfort, best for

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

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

Beautyrest Black Series Three 15.25" Medium Mattress

2287

Starting at

$4199⁰⁰

$4799⁰⁰

$600 OFF

Medium Comfort, best for

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

$300 ⁶ adjustable base instant gift with purchase.

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" Soft Mattress

1525

Starting at

$3899⁰⁰

$4399⁰⁰

$500 OFF

Plush Comfort, best for

Side Sleepers
Pain
Allergies
Bed Partner
Toss and Turn
Temperature

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

Beautyrest Black Series Three 16.75" Plush Pillow Top Mattress

1458

Starting at

$4599⁰⁰

$5199⁰⁰

$600 OFF

Plush Comfort, best for

Side Sleepers
Bed Partner
Pain
Temperature
Toss and Turn

$300 ⁶ adjustable base instant gift with purchase.

Tempur-Pedic TEMPUR-LuxeAdapt 2.0 13" Firm Mattress

1449

Starting at

$3899⁰⁰

$4399⁰⁰

$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

Serta Perfect Sleeper Oasis Sleep 14.5" Firm Pillow Top Mattress

1178

Starting at

$1399⁰⁰

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Serta Perfect Sleeper Sleep Excellence Extra Firm Mattress

955

Starting at

$1449⁹⁹

$1999⁹⁹

$550 OFF

Extra Firm Comfort, best for

Back, Stomach Sleepers
Pain
Toss and Turn
Temperature
Bed Partner

FREE ADJUSTABLE BASE ³ with code ELEVATE

Beautyrest Black Series Four 17.5" Medium Summit Pillow Top Mattress

605

Starting at

$5899⁰⁰

$6599⁰⁰

$700 OFF

Medium Comfort, best for

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

$300 ⁶ adjustable base instant gift with purchase.

Beautyrest Black Series Three 16.25" Medium Pillow Top Mattress

470

Starting at

$4599⁰⁰

$5199⁰⁰

$600 OFF

Medium Comfort, best for

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

$300 ⁶ adjustable base instant gift with purchase.

Firm height 84 mattresses are designed for sleepers who prefer a supportive, stable surface with a longer-than-standard sleep area. An 84-inch mattress can be a practical choice for taller sleepers, specialty bed frames, adjustable bases or select RV and bedroom setups that require additional length. Because mattress dimensions can vary by size and manufacturer, measure the available space before shopping and confirm the mattress length, width, thickness and foundation requirements. A firm mattress typically offers less sinkage than a plush or medium mattress, helping promote an even sleep surface and a supported feel for back and stomach sleepers. Consider your preferred sleep position, body type and comfort needs to find the right balance of firmness and pressure relief. Shopping for a firm 84-inch mattress also means comparing mattress height, materials and construction. Mattress height can affect how easy it is to get in and out of bed, the overall appearance of the bed and whether sheets, protectors and accessories fit correctly. Innerspring, memory foam, hybrid and latex mattresses may all be available in firm feels, but each construction provides a different type of support and responsiveness. Look for breathable materials and targeted comfort layers if you want firm support without an overly hard feel, and pair your mattress with a compatible foundation or adjustable base for dependable performance. With the right size and construction, an 84-inch firm mattress can help create a comfortable sleep setup that supports better zzz's night after night.

What makes a mattress firm? + -

A firm mattress has a more supportive feel with less give when you lie down. Its comfort comes from the combination of the comfort layers, support core and upholstery materials.

What types of materials are used in firm mattresses? + -

Firm mattresses may include materials such as innersprings, foam, memory foam, latex or a combination of these. Each material can create a different feel, from responsive and buoyant to contouring and pressure-relieving.

Are firm mattresses available in different comfort feels? + -

Yes. Firm mattresses can vary in feel depending on their construction. Some have a flatter, more supportive surface, while others include cushioning layers for a slightly more comfortable feel without losing firmness.

What type of foundation works with a firm mattress? + -

Many firm mattresses are compatible with a platform bed, adjustable base or traditional foundation. Always review the mattress manufacturer's recommendations to confirm which foundation types are suitable.

How can I care for a firm mattress? + -

Use a supportive foundation, rotate the mattress if the manufacturer recommends it and protect the surface with a breathable mattress protector. Follow the care instructions provided with your mattress for the best maintenance routine.