Cyber Monday Sale On King Size Memory Foam Mattresses

Explore king size memory foam mattresses for Cyber Monday, including plush, medium and firm options in a range of heights. Compare prices and mattress details to find the feel and profile that suit your sleep preferences, bed setup and budget.

Serta Perfect Sleeper Sleep Excellence Medium PillowTop Mattress

1467

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

Stearns & Foster Estate 14.5" Firm Mattress

1865

Starting at

$2899⁰⁰

$3099⁰⁰

$200 OFF

Firm Comfort, best for

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

$300 Instant Gift⁴ with purchase of a mattress set.

Stearns & Foster Lux Estate Elite 16" Medium Euro Pillow Top Mattress

1017

Starting at

$4299⁰⁰

$4699⁰⁰

$400 OFF

Medium Comfort, best for

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

$300 Instant Gift⁴ with purchase of a mattress set.

Tulo Bamboo 6" Firm Green Tea Memory Foam Mattress

5604

Starting at

$259⁹⁹

$729⁹⁹

$470 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

Nectar Classic 12" Firm Memory Foam Mattress

245

Starting at

$899⁰⁰

$1399⁰⁰

$500 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

Beautyrest Black Series Two 16.5" Medium Pillow Top Mattress

300

Starting at

$3699⁰⁰

$4099⁰⁰

$400 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 15.25" Medium Mattress

2385

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.

Stearns & Foster Studio 14" Medium Mattress

1393

Starting at

$2299⁰⁰

$2499⁰⁰

$200 OFF

Medium Comfort, best for

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

Beautyrest Black Series Three 15" Firm Mattress

2312

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.

Serta Perfect Sleeper Sleep Excellence Extra Firm Mattress

989

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

Stearns & Foster Lux Estate 14.5" Medium Mattress

759

Starting at

$3499⁰⁰

$3899⁰⁰

$400 OFF

Medium Comfort, best for

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

$300 Instant Gift⁴ with purchase of a mattress set.

Beautyrest Black Series Two 15.5" Medium Mattress

535

Starting at

$3499⁰⁰

$3899⁰⁰

$400 OFF

Medium Comfort, best for

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

$300 ⁶ adjustable base instant gift with purchase.

Stearns & Foster Studio 14.5" Medium Euro Pillow Top Mattress

151

Starting at

$2499⁰⁰

$2699⁰⁰

$200 OFF

Medium Comfort, best for

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

Stearns & Foster Estate 15" Firm Euro Pillow Top Mattress

2818

Starting at

$3099⁰⁰

$3299⁰⁰

$200 OFF

Firm Comfort, best for

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

$300 Instant Gift⁴ with purchase of a mattress set.

Sealy Posturepedic Elite Hybrid High Point II 14" Medium Mattress

1838

Starting at

$2899⁰⁰

$3099⁰⁰

$200 OFF

Medium Comfort, best for

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

$200 Instant Gift⁴ with purchase of a mattress set.

Stearns & Foster Lux Estate 16" Medium Euro Pillow Top Mattress

1832

Starting at

$4099⁰⁰

$4499⁰⁰

$400 OFF

Medium Comfort, best for

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

$300 Instant Gift⁴ with purchase of a mattress set.

Cyber Monday is an opportunity to compare king size memory foam mattresses and find comfort that fits your sleep preferences, bedroom and budget. A standard king mattress measures 76 inches wide by 80 inches long, offering room to stretch out or share your sleep space. Memory foam contours to your body, helping cushion pressure points at the shoulders and hips, while the mattress’s support layers help maintain alignment. For couples, memory foam can also help limit motion transfer, making a partner’s movements less noticeable during the night. As you browse Cyber Monday king mattress options at Mattress Firm, consider how you usually sleep rather than choosing by mattress thickness alone. Side sleepers may prefer more cushioning around pressure points, while back and stomach sleepers often benefit from a firmer feel that helps prevent excessive sinking. The right balance of cushioning and support depends on your body, comfort preferences and sleep position. Finding the right king size memory foam mattress for Cyber Monday also means looking beyond the surface feel. If you tend to sleep warm, compare models with breathable covers, ventilated foam or cooling materials, keeping in mind that temperature comfort varies by mattress construction, bedding and bedroom conditions. Review each mattress’s specifications to understand its firmness, foam layers and compatibility with your foundation or adjustable base. Before choosing a king memory foam mattress, measure your bedroom and delivery route, allowing space for nightstands, other furniture and comfortable movement around the bed. Compare current prices alongside delivery options, warranty details and any applicable trial or return terms so you understand the full purchase. Mattress Firm’s Sleep Experts® can help you narrow your choices based on how you sleep and what feels comfortable. With those practical details in place, you can approach Cyber Monday mattress shopping with a clearer sense of what matters for your nightly comfort.

What should I compare when browsing memory foam mattresses on Cyber Monday? + -

Compare firmness descriptions, foam layer materials, support core construction and cover details. Note the model names and numbers so you can keep track of the mattresses you're considering.

How does an all-foam mattress differ from a memory foam hybrid? + -

An all-foam mattress uses foam throughout its comfort layers and support core. A memory foam hybrid combines memory foam comfort layers with a coil support core. Check the construction details rather than relying on the mattress name alone.

What does memory foam density mean? + -

Density describes how much foam weighs per unit of volume. It is different from firmness: denser foam isn't necessarily firmer. Read the density information alongside the firmness description and layer construction.

What is gel-infused memory foam? + -

Gel-infused memory foam contains gel incorporated into the foam. It differs from a mattress with a separate gel layer, so review the material descriptions to understand how each mattress is constructed.

How should I care for a memory foam mattress cover? + -

Follow the manufacturer's care instructions for the specific cover. A removable cover isn't necessarily machine washable, so check its care label before laundering. If the cover isn't removable, follow the recommended spot-cleaning method.