Cyber Monday Medium King Size Mattresses Sale

Explore our Cyber Monday selection of medium king size mattresses to compare available king mattresses with a medium feel, along with their features, prices and delivery options. Find a comfortable fit for your sleep preferences and bedroom setup with options from trusted mattress brands.

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Sleepy's By Sealy Memory Foam Medium Mattress

3527

Starting at

$889⁹⁹

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Serta Perfect Sleeper Charlotte 2.0 Medium Euro Top Mattress

2621

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

Serta Perfect Sleeper Sleep Excellence Medium PillowTop Mattress

1449

Starting at

$1449⁹⁹

$1999⁹⁹

$550 OFF

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

3665

Starting at

$2029⁷⁷

$2899⁰⁰

$869 OFF

Medium Comfort, best for

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

Beautyrest PressureSmart 2.0 Hybrid Medium 13" Mattress

1758

Starting at

$1474⁷⁷

$2949⁹⁹

$1475 OFF

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Beautyrest BR800 13.5" Medium Pillow Top Mattress

1878

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

Tulo Bamboo 8" Medium Green Tea Memory Foam Mattress

5575

Starting at

$809⁹⁹

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Beautyrest Silver BRS900 11.75" Medium Firm Mattress

1756

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

Purple Original Mattress

59773

Starting at

$2199⁰⁰

Medium Comfort, best for

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

Sleepy's By Sealy Slumber Cushion Firm Mattress

304

Starting at

$619⁹⁹

$1999⁹⁹

$1380 OFF

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Sleepy's By Sealy Slumber Medium Mattress

184

Starting at

$2299⁹⁹

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Sealy Essentials Winter Green 12" Medium Euro Top Mattress

604

Starting at

$1379⁹⁹

Medium Comfort, best for

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

Beautyrest Black Series Two 16.5" Medium Pillow Top Mattress

295

Starting at

$4099⁰⁰

Medium Comfort, best for

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

$300 ⁶ adjustable base instant gift with purchase.

Tempur-Pedic TEMPUR-ProAdapt 2.0 12" Medium Hybrid Mattress

6084

Starting at

$4199⁰⁰

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

Tempur-Pedic TEMPUR-ProAdapt 2.0 12" Medium Mattress

3905

Starting at

$4199⁰⁰

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

2320

Starting at

$4799⁰⁰

Medium Comfort, best for

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

$300 ⁶ adjustable base instant gift with purchase.

A Cyber Monday medium king size mattress promotion is a smart opportunity to upgrade your sleep space with the balanced comfort and spacious feel of a king mattress. Medium-feel mattresses are designed to provide a versatile combination of cushioning and support, making them a popular choice for sleepers who want pressure relief without an overly soft sensation. With extra room for couples, families and restless sleepers, a medium king size mattress can help promote more comfortable rest while complementing a king bed frame, adjustable base or complete bedroom setup. Explore options with memory foam, innerspring and hybrid construction to find the right combination of contouring comfort, responsive support and temperature management for your sleep style. Shopping the Cyber Monday mattress event at Mattress Firm can make it easier to compare medium king size mattresses from trusted brands and discover special pricing on a mattress built for lasting comfort. Look for features such as reinforced edge support, breathable comfort layers, individually wrapped coils and motion isolation to help create a more relaxing sleep environment. Whether you prefer the adaptive feel of TEMPUR-Material™, the responsive support of a hybrid mattress or the familiar bounce of an innerspring mattress, a medium king mattress offers a comfortable middle ground for many sleepers. Compare mattress sizes, firmness levels and available offers to find a king size mattress that helps you sleep well so you can live well.

What does a medium-feel mattress mean? + -

A medium-feel mattress offers a balance between cushioning and support, making it a versatile choice for shoppers who prefer a comfort level that is neither very firm nor very plush.

What materials are commonly used in medium-feel mattresses? + -

Medium-feel mattresses may include memory foam, innersprings, hybrid layers or latex. Each material creates a different feel, so compare the construction and comfort layers when shopping.

How do I compare medium-feel mattresses during Cyber Monday? + -

Review each mattress’s construction, comfort layers, support system and included features. Reading product details can help you compare options and find a feel that matches your preferences.

How do I care for a medium-feel mattress? + -

Use a supportive foundation, rotate the mattress according to the manufacturer’s recommendations and protect it with a properly fitted mattress protector. Follow the care instructions for your specific mattress.

Can I use a medium-feel mattress with an adjustable base? + -

Many medium-feel mattresses are designed to work with adjustable bases. Check the manufacturer’s compatibility guidelines before pairing the mattress with a base.