Soft King Mattresses For Side Sleepers

Shop Soft King Mattresses For Side Sleepers at Mattress Firm to explore a range of king size options selected for shoppers seeking a softer sleep surface. Compare choices by size, comfort preference and more to find a mattress that suits your bedroom and sleep routine.

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Sleepy's By Sealy Memory Foam Medium Mattress

3474

Starting at

$589⁹⁹

$889⁹⁹

$300 OFF

Medium Comfort, best for

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

Beautyrest PressureSmart 2.0 Plush 11.75" Mattress

6251

Starting at

$1149⁹⁹

$2299⁹⁹

$1150 OFF

Plush Comfort, best for

Side Sleepers
Temperature
Bed Partner
Pain
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Sleepy's By Sealy Memory Foam Plush Mattress

2776

Starting at

$699⁹⁹

$999⁹⁹

$300 OFF

Plush Comfort, best for

Side 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

2615

Starting at

$839⁹⁹

$1499⁹⁹

$660 OFF

Medium Comfort, best for

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

FREE ADJUSTABLE BASE ³ with code ELEVATE

Beautyrest PressureSmart 2.0 Plush Pillow Top 13.75" Mattress

2695

Starting at

$1199⁹⁹

$2399⁹⁹

$1200 OFF

Plush Comfort, best for

Side Sleepers
Temperature
Bed Partner
Pain
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

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

$2029⁷⁷

$2899⁰⁰

$869 OFF

Medium Comfort, best for

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

Beautyrest BR800 13.5" Plush Pillow Top Mattress

2784

Starting at

$819⁹⁹

$1499⁹⁹

$680 OFF

Plush Comfort, best for

Side Sleepers
Toss and Turn
Pain
Bed Partner
Temperature

FREE ADJUSTABLE BASE ³ with code ELEVATE

Tulo Bamboo 10" Medium Green Tea Memory Foam Mattress

5555

Starting at

$379⁹⁹

$889⁹⁹

$510 OFF

Medium Comfort, best for

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

Tulo Bamboo 12" Medium Plush Green Tea Memory Foam Mattress

5555

Starting at

$429⁹⁹

$1019⁹⁹

$590 OFF

Medium Comfort, best for

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

Tulo Bamboo 8" Medium Green Tea Memory Foam Mattress

5555

Starting at

$329⁹⁹

$809⁹⁹

$480 OFF

Medium Comfort, best for

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

Purple Original Mattress

59743

Starting at

$1760⁰⁰

$2199⁰⁰

$439 OFF

Medium Comfort, best for

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

Sealy Essentials Winter Green 13" Plush Euro Pillow Top Mattress

548

Starting at

$779⁹⁹

$1459⁹⁹

$680 OFF

Plush Comfort, best for

Side Sleepers
Bed Partner
Pain
Temperature
Toss and Turn
Allergies

Beautyrest BR800 12" Plush Euro Top Mattress

735

Starting at

$569⁹⁹

$1399⁹⁹

$830 OFF

Plush Comfort, best for

Side Sleepers
Toss and Turn
Pain
Bed Partner
Temperature

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

981

Starting at

$4099⁰⁰

$4699⁰⁰

$600 OFF

Medium Comfort, best for

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

Receive $300 Instant Gift⁴ with purchase.

Sleepy's By Sealy Slumber Medium Mattress

175

Starting at

$709⁹⁹

$2299⁹⁹

$1590 OFF

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

603

Starting at

$739⁹⁹

$1379⁹⁹

$640 OFF

Medium Comfort, best for

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

Beautyrest Silver BRS900 12" Plush Mattress

1140

Starting at

$729⁹⁹

$1699⁹⁹

$970 OFF

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

$979⁰⁰

$1249⁰⁰

$270 OFF

Plush Comfort, best for

Side Sleepers
Pain
Temperature
Bed Partner
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Serta Perfect Sleeper Elkins III 11" Plush Euro Top Mattress

1610

Starting at

$599⁹⁹

$1199⁹⁹

$600 OFF

Plush Comfort, best for

Side Sleepers
Pain
Temperature
Toss and Turn
Bed Partner

FREE ADJUSTABLE BASE ³ with code ELEVATE

Nectar Premier 13" Medium Memory Foam Mattress

486

Starting at

$1099⁰⁰

$1799⁰⁰

$700 OFF

Medium Comfort, best for

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

Nectar Luxe 14" Medium Memory Foam Mattress

238

Starting at

$1649⁰⁰

$2249⁰⁰

$600 OFF

Medium Comfort, best for

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

Serta Perfect Sleeper Nurture Night 13.5" Medium Mattress

1020

Starting at

$939⁰⁰

$1099⁰⁰

$160 OFF

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 14.5" Pillow Top Mattress

1009

Starting at

$1139⁰⁰

$1399⁰⁰

$260 OFF

Medium Comfort, best for

Back, Side, 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

$939⁰⁰

$1099⁰⁰

$160 OFF

Plush Comfort, best for

Side Sleepers
Pain
Bed Partner
Temperature
Toss and Turn

FREE ADJUSTABLE BASE ³ with code ELEVATE

Sealy Essentials Winter Green 12" Plush Euro Top Mattress

393

Starting at

$739⁹⁹

$1379⁹⁹

$640 OFF

Plush Comfort, best for

Side Sleepers
Bed Partner
Pain
Temperature
Toss and Turn
Allergies

A soft king mattress can give side sleepers the spacious comfort and pressure relief they need for more restful zzz's. Sleeping on your side places extra pressure on the shoulders, hips and knees, so a plush comfort layer can help cushion these areas while allowing the body to settle into a more natural position. Look for a soft king mattress with contouring memory foam, responsive latex or a pillow top designed to relieve pressure without creating an overly sinking feel. The best king mattress for side sleepers should also provide supportive layers beneath the surface to help promote proper spinal alignment, keeping the hips from dipping too far into the mattress. With generous space for couples, a king size mattress measures approximately 76 inches wide by 80 inches long, making it a comfortable choice for sleepers who prefer room to stretch out. Choosing the right soft mattress for side sleeping means balancing plush comfort with dependable support. A mattress that feels soft on top but includes reinforced edges, individually wrapped coils or a supportive foam core can help improve stability and make it easier to move across the surface. Side sleepers may also appreciate pressure-relieving features such as gel-infused memory foam for a cooler feel, breathable comfort materials or motion isolation that limits disturbances from a partner. Compare soft king mattresses by considering your body type, preferred sleep position, temperature preferences and desired level of responsiveness. Adding a supportive pillow that fills the space between your head and the mattress can further support neutral alignment, helping your soft king bed feel comfortable from bedtime through morning.

What makes a soft mattress a good choice for side sleepers? + -

Soft mattresses can allow the shoulders and hips to sink in comfortably, helping create a more even feel along the body. Side sleepers often prefer a cushioned comfort layer made with materials such as memory foam, latex or plush fiber.

How soft should a mattress be for side sleeping? + -

The ideal softness depends on body type, personal preference and how much cushioning feels comfortable. Look for a mattress that feels plush around the shoulders and hips while still providing a supportive foundation underneath.

Which mattress materials are commonly found in soft mattresses for side sleepers? + -

Memory foam, TEMPUR-Material™ and soft latex are common choices for a cushioned feel. Hybrid mattresses may also combine plush comfort layers with individually wrapped coils for a blend of contouring and responsive support.

Can soft mattresses for side sleepers have different comfort feels? + -

Yes. A soft mattress may feel gently cushioned, deeply contouring or lightly buoyant depending on its materials and construction. Comparing comfort layers, mattress height and the overall design can help you find the feel that suits your preferences.

What should side sleepers look for in a soft mattress? + -

Consider a mattress with cushioning through the comfort layers, a supportive base and enough contouring around the shoulders and hips. Motion isolation and breathable materials may also be important features, especially if you share your bed.