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King Grey Mattresses All Mattresses

King mattresses measure 76" × 80" — the widest standard size, giving each partner the same personal space as a twin. They're the top choice for couples who want maximum room, families who co-sleep, and larger master bedrooms. Compare every king option below by brand, feel, and price.
These mattresses feature a grey or neutral-tone cover — and since that cover sits under your sheets, colour won't change how you sleep. To find the right bed, shop by size (twin to king), comfort (plush, medium, firm), or type (memory foam, hybrid, pocket coil). Every mattress includes a 365-night sleep trial and free delivery across Canada.

Shop a wide range of mattresses from Serta, Beautyrest, Sealy, Tempur-Pedic, Springwall, and Stearns & Foster at National Mattress, available in Single/Twin through King sizes, from budget-friendly to luxury. Choose from innerspring, euro-top, memory foam, hybrid, and latex constructions in four firmness levels from extra firm to plush. Every mattress is manufactured in Canadian factories using CertiPUR-US® certified foams and ships free across Canada with a 365-night sleep trial, price match guarantee, and coverage under the manufacturer warranty terms.

King Grey Mattresses All Mattresses
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  • Beautyrest 13-inch medium-firm tight-top mattress, flat grey ribbed quilting with teal accents Beautyrest Mattress Collection Logo
    • 875 Beautyrest® Pocketed Coil Technology
    • Beautyrest® ActiveResponse Memory Foam
    • SurfaceTouch™ Gel Memory Foam
    • Beautyrest® Plush Gel Foam
    • InfiniCool™ Technology
    • Beautyrest® Antimicrobial Fibre Technology
    King $1,034
    Compare at $2,399
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 on Tue, Sep 29
  • Sealy Posturepedic Plus 1000 Series 12.5-inch medium-firm euro-top mattress, white-blue tufted top, grey sides Sealy Posturepedic Plus Mattress Logo
    • CleanProtect™ Cover
    • SealyAir™ Fibres
    • CertiPUR-US™ SealyComfort™ Gel HD Foam
    • SealyResponse™ HD Pocket Coils
    • StableEdge™ HD
    • PROBACK® Quilt with Targeted GelBoost™ HD Memory Foam
    King $1,117
    Compare at $2,599
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 on Tue, Sep 29
  • Sealy Posturepedic Plus 1000 Series 14-inch plush euro-pillow-top mattress, domed white-blue top, grey sides Sealy Posturepedic Plus Mattress Logo
    • CleanProtect™ Cover
    • SealyAir™ Fibres
    • CertiPUR-US™ SealyComfort™ Gel HD Foam
    • SealyResponse™ HD Pocket Coils
    • StableEdge™ HD
    • PROBACK® Quilt with Targeted GelBoost™ HD Memory Foam
    King $1,190
    Compare at $2,799
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 on Tue, Sep 29
  • Beautyrest 15-inch plush pillow-top mattress, grey ribbed top with teal wave accents, charcoal sides, teal piping and handles Beautyrest Mattress Collection Logo
    • 875 Beautyrest® Pocketed Coil Technology
    • Beautyrest® ActiveResponse Memory Foam
    • SurfaceTouch™ Gel Memory Foam
    • Beautyrest® Plush Gel Foam
    • InfiniCool™ Technology
    • Beautyrest® Antimicrobial Fibre Technology
    King $1,199
    Compare at $2,799
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 on Tue, Sep 29
  • Beautyrest 15-inch firm pillow-top mattress, tall profile, grey quilted top with teal swirls, charcoal sides Beautyrest Mattress Collection Logo
    • 875 Beautyrest® Pocketed Coil Technology
    • Beautyrest® ActiveResponse Memory Foam
    • SurfaceTouch™ Gel Memory Foam
    • Beautyrest® Medium+Firm Gel Foam
    • InfiniCool™ Technology
    • Beautyrest® Antimicrobial Fibre Technology
    King $1,199
    Compare at $2,799
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 on Tue, Sep 29
  • Sealy Posturepedic Luxury 13.5-inch firm hybrid tight-top King mattress, navy swirl cover, charcoal side Sealy Posturepedic Luxury Mattress Logo
    • SealyMAX™ Core System featuring SealyResponse™ PRO & SolidSupport™ Pocket Coils
    • GelSense™ MAX Memory Foam
    • SealySupport™ Gel HD Foam
    • SupremeLoft™ Quilt featuring Silk & Wool
    • SealyCool™ Fabric
    • SolidEdge™ PRO Coil Edge
    King $1,307
    Compare at $3,099
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 on Tue, Sep 29
  • Sealy Natural Origins 13.5-inch firm tight-top latex mattress, flat tufted white top, grey-black diamond sides Sealy Natural Origins Mattress Logo
    • OEKO-TEX Certified BioGel Latex
    • SealyCool Fibres with Silk & Wool
    • Organic Cotton Infused with Bamboo
    • Targeted ComfortSense Memory Foam
    • SealySupport HD Core
    • CertiPUR-US® Approved Foam
    King $1,322
    Compare at $3,099
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 on Tue, Sep 29
  • Springwall Luxury Chiropractic 13.5-inch firm tight-top mattress, tan flat top, grey sides, copper piping Springwall H2 Chiropractic Luxury Mattress Logo
    • 2400 7-Zoned Chiropractic® Pocket Coils
    • Luxurious Surface Fabric & Phase-Changing Properties
    • AIRWAYS™ Specialty Foam
    • HD Bio Comfort Foam
    • Handcrafted and Individually Signed For Authenticity
    King In stock for fast delivery $1,353
    Compare at $2,999
    Online availability icon In-Stock Only 1 left!
    In-Store availability icon On Display:
    Free delivery availability icon Free delivery to M5H 2N1 as soon as Tomorrow, Sep 14
    Pickup available icon Only Pickup available to
    M5H 2N1
  • Beautyrest World Class 12.5-inch hybrid medium-firm mattress, angled view with blue chevron top and blue trim Beautyrest World Class Mattress Collection Logo
    • 1000 Beautyrest® Pocketed Coil Technology
    • Beautyrest® ActiveResponse Memory Foam
    • Beautyrest® Medium Gel Foam
    • World Class Relief™ HD Foam
    • InfiniCool™ Technology
    King In stock for fast delivery $1,363
    Compare at $3,199
    Online availability icon In-Stock Only 1 left!
    In-Store availability icon On Display:
    Free delivery availability icon Free delivery to M5H 2N1 as soon as Tomorrow, Sep 14
    Pickup available icon Only Pickup available to
    M5H 2N1
  • Beautyrest World Class 12.5-inch firm hybrid mattress, low-profile teal chevron tight-top, grey sides Beautyrest World Class Mattress Collection Logo
    • 1000 Beautyrest® Pocketed Coil Technology
    • Beautyrest® ActiveResponse Memory Foam
    • Beautyrest® Firm Gel Foam
    • World Class Relief™ HD Foam
    • InfiniCool™ Technology
    King $1,363
    Compare at $3,199
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 on Tue, Sep 29
  • Sealy Posturepedic Luxury 14.5-inch medium-firm hybrid euro-top mattress, quilted white top, charcoal sides Sealy Posturepedic Luxury Mattress Logo
    • SealyMAX™ Core System featuring SealyResponse™ PRO & SolidSupport™ Pocket Coils
    • GelSense™ MAX Memory Foam
    • SealySupport™ Gel HD Foam
    • SupremeLoft™ Quilt featuring Silk & Wool
    • SealyCool™ Fabric
    • SolidEdge™ PRO Coil Edge
    King $1,371
    Compare at $3,299
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 on Tue, Sep 29
  • Springwall Luxury Chiropractic 14.5-inch firm euro-top mattress, tan crown, grey sides, copper piping Springwall H2 Chiropractic Luxury Mattress Logo
    • 2400 7-Zoned Chiropractic® Pocket Coils
    • Luxurious Surface Fabric & Phase-Changing Properties
    • AIRWAYS™ Specialty Foam
    • HD Bio Comfort Foam
    • Handcrafted and Individually Signed For Authenticity
    King In stock for fast delivery $1,432
    Compare at $3,099
    Online availability icon In-Stock Only 2 left!
    In-Store availability icon On Display:
    Free delivery availability icon Free delivery to M5H 2N1 as soon as Tomorrow, Sep 14
    Pickup available icon Only Pickup available to
    M5H 2N1

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How to Choose a Mattress

Choosing a mattress comes down to three decisions: what holds you up, how firm it feels, and what size fits your room and the people in the bed. Everything else follows from those. The support layer underneath determines how the bed behaves over years of use, while the comfort layers on top decide how it feels on the first night, and the two are worth judging separately. National Mattress carries innerspring, hybrid, memory foam and latex construction from Sealy, Serta, Beautyrest, Stearns & Foster, Tempur-Pedic, MLILY, Chirofoam, Springwall, Marshall Mattress, Evergreen and our own NM line.

Firmness is a fit rather than a quality rating. Side sleepers usually want medium or plush, so the shoulder and hip can sink far enough to keep the spine straight. Back sleepers usually want medium to firm, which fills the lumbar curve. Stomach sleepers want the firm end, so the hips are not allowed to drop below the ribs, and extra firm belongs there and to heavier sleepers. If you share the bed and your answers differ, a pocketed coil support system limits how much of your movement reaches the other side, and choosing a larger size does more for a shared bed than any single feature. Firmness on our mattresses runs extra firm, firm, medium and plush.

🛏 Coil, Foam, Hybrid or Latex

In a pocket coil bed each spring sits in its own fabric pocket and compresses on its own, so far less of your movement reaches the other side. A connected coil unit links the springs together for a firmer, more uniform surface at a lower price. All-foam beds contour closely and make no noise. Latex is springier than memory foam and does not hold heat the same way.

💤 Firmness by Sleep Position

Side sleepers need the surface to give at the shoulder and hip. Back sleepers want medium to firm, enough to fill the lumbar curve without flattening it. Stomach sleepers want the firm end, which keeps the hips level with the ribs. If you move between positions all night, medium is the safest place to start. Body weight shifts this too: a heavier sleeper compresses any comfort layer further and generally reads a mattress as softer than a lighter sleeper does.

👥 Sharing the Bed

Two things decide whether a shared bed works: motion transfer and edge support. Pocketed coils and a foam-encased perimeter mean far less of your movement reaches the other side, and they keep the outer few inches usable rather than collapsing when you sit on them. If one of you sleeps hot, that is a materials question, and it is worth solving on the comfort layer rather than compromising on firmness.

📏 Get the Size Right First

Size is the one decision you cannot adjust later with a topper. Measure the room, then measure the route in: stairwell turns, doorways and elevator depth are what actually stop a delivery. A queen suits most couples, a king buys shoulder room, and twin XL is the length growing teenagers and taller single sleepers need.

Frequently Asked Questions About Choosing a Mattress

How do I know which firmness I need?
Start from the position you fall asleep in. Side sleepers generally do best on medium or plush, because the shoulder and hip need somewhere to go before the spine can stay neutral. Back sleepers generally do best on medium to firm, which fills the lumbar curve. Stomach sleepers want the firm end, which stops the hips sinking below the ribs. Combination sleepers should start at medium. Your body weight matters as well, since a heavier sleeper reads the same mattress as softer than a lighter one does.
What is the difference between pocket coils and a connected coil unit?
In a pocket coil mattress every spring sits in its own fabric pocket and compresses independently, so far less of one sleeper's movement reaches the other side. A connected coil unit links the springs together instead, and that is a family: Bonnell laces separate hourglass coils with helical wire, and only a continuous unit is bent from a single strand. That makes for a firm, uniform, durable surface and usually a lower price, but more of any movement travels across the bed.
Is a hybrid better than an all-foam mattress?
Neither is better outright, they fail differently. A hybrid puts foam or latex comfort layers over a coil support core, so it gives you contouring with more bounce, stronger edges and more airflow through the middle of the bed. An all-foam mattress contours more closely, isolates motion almost completely and is silent, but it warms up more, and gel or graphite infusion only slows the warm-up; sustained cooling comes from airflow. Hot sleepers and people who dislike a sinking feeling usually prefer a hybrid.
How long should a mattress last before I replace it?
Watch the mattress rather than the calendar. The signals that matter are a visible dip where you sleep, waking with stiffness that eases once you are up, or sleeping noticeably better away from home. Construction changes the answer a good deal, since a dense foam core and a pocket coil unit age differently from an entry-level foam bed. Our guide to mattress lifespan by type sets out what to expect from each.
Do I need a new boxspring or foundation as well?
Usually yes if the old one is sagging, because a mattress can only be as flat as what it sits on, and a dip underneath will show through a new mattress within months. Foam and hybrid mattresses want a solid or closely slatted platform, and slats spaced too widely let the mattress bow between them. If you are considering an adjustable base instead, the mattress has to be able to flex, which not every construction can do.
Which mattress size should I buy?
Work backwards from the room and the sleepers. A queen is the usual choice for two adults and fits most bedrooms with space to walk around the bed. A king adds width for couples who want to move without touching, and a split king lets each side sit on its own adjustable base. Twin XL adds length for taller sleepers. Our guide to standard Canadian mattress sizes lists the measurements.

Not Sure Where to Start?

Answer a few questions about how you sleep and we will narrow the field for you, or talk it through with someone whose pay does not depend on which mattress you choose. Our non-commissioned sleep experts can put two beds side by side and tell you what actually separates them.

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