King Soft Knit Cover Mattresses

Find comfort that fits your space with King Soft Knit Cover Mattresses from Mattress Firm. Explore a range of king-size options to help you create a sleep setup that suits your bedroom and routine, with choices available at different price points and preferences.

Sealy Essentials Spruce 5.5" Firm Mattress

1373

Starting at

$549⁹⁹

$949⁹⁹

$400 OFF

Firm Comfort, best for

Back, Stomach Sleepers
Pain
Temperature
Bed Partner
Toss and Turn

Tulo Green Tea 12" Plush Mattress

Starting at

$1399⁹⁹

Plush Comfort, best for

Side Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

Tulo Green Tea 10" Medium Mattress

Starting at

$419⁹⁹

$1249⁹⁹

$830 OFF

Medium Comfort, best for

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

Sleepy's By Sealy Skye Hybrid Mattress

2453

Starting at

$999⁹⁹

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Tempur-Pedic TEMPUR-Adapt 2.0 11" Medium Mattress

3782

Starting at

$2799⁰⁰

$2999⁰⁰

$200 OFF

Medium Comfort, best for

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

$300 Instant Gift⁴ with purchase of a mattress set + Calm app 3-month free trial.

Sierra Sleep By Ashley Peak 2.0 12" Memory Foam Mattress

Starting at

$1549⁹⁹

Plush Comfort, best for

Side Sleepers
Pain
Bed Partner
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Sierra Sleep By Ashley Peak 2.0 8" Memory Foam Mattress

Starting at

$1149⁹⁹

Medium Comfort, best for

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

Tulo Green Tea 8" Medium Mattress

Starting at

$1069⁹⁹

Medium Comfort, best for

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

Sierra Sleep By Ashley Peak 2.0 10" Memory Foam Mattress

Starting at

$569⁹⁹

$1399⁹⁹

$830 OFF

Medium Comfort, best for

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

Tulo Bamboo 10" Medium Green Tea Memory Foam Mattress

5601

Starting at

$889⁹⁹

Medium Comfort, best for

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

Serta Classic Blissville 11.5" Medium Mattress

174

Starting at

$659⁹⁹

$1699⁹⁹

$1040 OFF

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Tulo Bamboo 12" Medium Plush Green Tea Memory Foam Mattress

5601

Starting at

$1019⁹⁹

Medium Comfort, best for

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

Sealy Posturepedic Elite Albany II 15" Soft Pillow Top Mattress

Starting at

$2399⁰⁰

$2499⁰⁰

$100 OFF

Plush Comfort, best for

Side Sleepers
Pain
Temperature
Allergies
Bed Partner
Toss and Turn

$200 Instant Gift⁴ with purchase of a mattress set.

Tempur-Pedic TEMPUR-ProAdapt 2.0 12" Soft Mattress

3564

Starting at

$3999⁰⁰

$4199⁰⁰

$200 OFF

Plush Comfort, best for

Side Sleepers
Pain
Allergies
Bed Partner
Toss and Turn
Temperature

$300 Instant Gift⁴ with purchase of a mattress set + Calm app 3-month free trial.

Purple RestorePlus 13" Soft Hybrid Mattress

3568

Starting at

$3999⁰⁰

$4399⁰⁰

$400 OFF

Plush Comfort, best for

Side Sleepers
Pain
Allergies
Bed Partner
Toss and Turn
Temperature

Dreamcloud Luxe Hybrid Mattress

Starting at

$1799⁰⁰

$3997⁵⁰

$2199 OFF

Medium Comfort, best for

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

Tulo Bamboo 8" Medium Green Tea Memory Foam Mattress

5601

Starting at

$809⁹⁹

Medium Comfort, best for

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

Stearns & Foster Reserve 17" Plush Euro Pillow Top Mattress

473

Starting at

$5399⁰⁰

$6199⁰⁰

$800 OFF

Plush Comfort, best for

Side Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

$300 Instant Gift⁴ with purchase of a mattress set.

Tempur-Pedic TEMPUR-LuxeAdapt 2.0 13" Soft Mattress

1580

Starting at

$5299⁰⁰

$5599⁰⁰

$300 OFF

Plush Comfort, best for

Side Sleepers
Pain
Allergies
Bed Partner
Toss and Turn
Temperature

$300 Instant Gift⁴ with purchase of a mattress set + Calm app 3-month free trial.

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

836

Starting at

$3799⁰⁰

$4199⁰⁰

$400 OFF

Plush Comfort, best for

Side Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

$300 Instant Gift⁴ with purchase of a mattress set.

Sealy Posturepedic Elite Hybrid High Point II 14" Soft Mattress

587

Starting at

$2899⁰⁰

$3099⁰⁰

$200 OFF

Plush Comfort, best for

Side Sleepers
Pain
Temperature
Allergies
Bed Partner
Toss and Turn

$200 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

Sealy Posturepedic Elite Hybrid Brenham II 14" Soft Mattress

Starting at

$2699⁰⁰

$2799⁰⁰

$100 OFF

Plush Comfort, best for

Side Sleepers
Pain
Temperature
Allergies
Bed Partner
Toss and Turn

$200 Instant Gift⁴ with purchase of a mattress set.

Sealy Posturepedic Pro Lacey II 15" Soft Pillow Top Mattress

Starting at

$2049⁰⁰

$2749⁰⁰

$700 OFF

Plush Comfort, best for

Side Sleepers
Pain
Temperature
Allergies
Bed Partner
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Stearns & Foster Reserve 16" Medium Mattress

276

Starting at

$4699⁰⁰

$5499⁰⁰

$800 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.

Sealy Tanglewood 2.0 Plush Euro Pillowtop Mattress

Starting at

$749⁷⁷

$1499⁹⁹

$750 OFF

Plush Comfort, best for

Side Sleepers
Temperature
Pain
Bed Partner
Toss and Turn

King soft knit cover mattresses combine the generous sleeping space of a king mattress with a flexible, smooth-feeling surface designed to complement the comfort layers underneath. A knit cover is made with interlocking loops rather than a tightly woven construction, which gives it a gentle stretch and a more relaxed hand feel. That flexibility can allow the cover to move with cushioning materials such as memory foam, latex or pillow-top padding instead of creating a stiff layer between you and the mattress. Many soft knit covers also support airflow across the surface, which can be helpful for sleepers who prefer a fresher, less enclosed feel as they settle in for the night. Some covers include moisture-wicking fibers or cooling treatments, but features vary, so it is worth reviewing the materials and care instructions for each mattress. The word “soft” in this category generally describes the surface feel or overall comfort level, not the cover alone. A soft knit cover can be paired with a plush, medium or even more supportive mattress design, so compare the complete comfort profile rather than relying on the fabric description by itself. For a closer look at related sleep solutions, explore Soft Knit Cover Beds.

A king mattress measures about 76 inches wide by 80 inches long, giving couples room to spread out without sharing the same narrow sleep space. It can also suit a single sleeper who enjoys extra room for changing positions, reading before bed or accommodating a child or pet on occasion, although sharing a mattress with pets or children may affect temperature, motion and available space. Soft knit cover mattresses may be especially appealing to side sleepers who like a cushioned first impression around the shoulders and hips, but the right choice still depends on the support system beneath the cover. Memory foam can provide contouring and motion isolation, while a hybrid design may combine pressure relief with the responsive feel and airflow of coils. Innerspring options often feel more buoyant and easier to move across, and latex can offer a springy, resilient surface. Stomach sleepers typically need enough support to help keep the midsection from sinking too deeply, while back sleepers often look for a balance of cushioning and stable lumbar support. Couples should also consider motion transfer, edge support and each person’s preferred firmness. A split king setup can make sense when two sleepers want different comfort levels or an adjustable base, though it creates a seam down the center. Before purchasing, measure the bedroom and the path into it, including doorways, stairways and tight corners. Leave enough room to walk around the bed, open drawers and make the bed without brushing against nearby furniture. A king mattress can transform a spacious bedroom into a comfortable retreat, but it should fit the room as thoughtfully as it fits the sleepers.

The cover is only one part of the sleep experience, so consider the full mattress construction, the bed frame or foundation it requires and the bedding you plan to use with it. A thick mattress may need deep-pocket sheets, and a stretchy knit surface can feel different beneath crisp cotton, brushed bedding or a lighter layer intended for warmer nights. During the cooler months, soft textures and supportive cushioning can make the bed feel inviting after a long day, while breathable materials may help prevent the heavy, overheated feeling that sometimes comes with piling on layers. If you tend to sleep warm, look for clear information about airflow, cooling fibers, coil systems and temperature-regulating materials instead of assuming that every knit cover performs the same way. If you wake with pressure at the shoulders or hips, a plush comfort layer may be useful, but excessive sink can make changing positions harder or leave you feeling unsupported. Partners with different preferences may want to compare firmness, responsiveness and motion isolation before choosing a shared king mattress. A mattress can also be a thoughtful household gift for a couple moving into a larger home, newlyweds setting up a bedroom or loved ones replacing an old sleep surface, but the recipient’s room size, preferred feel and foundation requirements should guide the decision. Give a new mattress time to fully expand and settle according to the manufacturer’s instructions, use an appropriate foundation and rotate it only when the care guidance recommends doing so. With the right combination of supportive construction, comfortable firmness, breathable bedding and a soft knit cover, a king mattress can create a welcoming place to rest, recharge and start the day feeling ready for what comes next.

What is a soft knit cover mattress? + -

A soft knit cover mattress features a flexible, fabric cover designed to provide a smooth, comfortable surface. The cover may be paired with comfort layers made from materials such as memory foam, latex or gel foam.

What does a soft knit mattress cover feel like? + -

Soft knit covers typically feel smooth, flexible and comfortable against bedding. Their stretchable construction can contour to the mattress layers while maintaining a gentle surface feel.

What materials are used in soft knit mattress covers? + -

Soft knit mattress covers may be made with polyester, cotton, rayon or blended fabrics. Some designs also include specialty fibers or quilted layers for added texture and cushioning.

How does a soft knit cover affect a mattress? + -

A soft knit cover adds a comfortable fabric layer over the mattress and can complement the feel of the layers underneath. Its flexible construction allows the surface to move with the mattress rather than creating a firm, rigid barrier.

How should you care for a mattress with a soft knit cover? + -

Use a properly fitted mattress protector to help keep the cover clean, and follow the care instructions provided with the mattress. Avoid removing or washing the cover unless it is specifically designed for that purpose.