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King Extra Firm Edge Support Mattresses Adjustable Bed Compatible Mattresses NM® Mattresses and Accessories

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.
Extra firm mattresses are the firmest, most supportive feel we carry — a hard, no-sink surface that holds your body on top of the mattress rather than letting it settle in. They're built for stomach sleepers, heavier-weight sleepers and anyone who finds a standard firm mattress still too soft, delivering maximum support and spinal alignment. Most use a tight-top or high-density foam construction (including orthopedic Chirofoam), with budget-friendly options that keep extra-firm support affordable. Shop Beautyrest, Serta, Chirofoam, Springwall and our own NM line — from $152, with free delivery across Canada. • Feel: extra firm is the firmest of our four comfort levels — a hard, no-sink surface • Best for: stomach sleepers, heavier-weight sleepers, and anyone who wants maximum support • Choose this over firm if a standard firm mattress still feels too soft • Consider firm or medium if you sleep on your side or want any cushioning • Constructions: tight-top and high-density foam (including orthopedic Chirofoam) • Brands: Beautyrest, Serta, Chirofoam, Springwall & NM • Prices: from $152 — an affordable, value-focused selection
Edge support mattresses are reinforced around the perimeter so the edge feels as solid as the middle — you can sleep right up to the side without that sinking, roll-off feeling, sit on the edge to get dressed without it caving, and use the full surface of the bed. It's a feature that matters most for couples sharing the space, anyone who sits on the edge to get in and out of bed, and heavier-weight sleepers. These are mostly our pocket-coil and hybrid mattresses with full-perimeter coils or foam-encased edges — from Springwall (Full Perimeter Comfort Pockets), Sealy, Serta, Beautyrest, iComfort, Stearns & Foster and our own NM line. Every mattress includes a 365-night sleep trial and free delivery across Canada. • What it does: a reinforced perimeter so the edge stays firm — no sinking or rolling off • Why it matters: more usable sleep surface, easier to sit on the edge and get in and out of bed • Best for: couples sharing space, anyone who sits on the edge, and heavier-weight sleepers • How it works: full-perimeter pocket coils or foam-encased edges (mostly coil & hybrid; all-foam edges are softer) • Brands: Springwall (Full Perimeter Comfort Pockets), Sealy, Serta, Beautyrest, iComfort, Stearns & Foster & NM • Every order: 365-night sleep trial, price-match guarantee & free Canada-wide delivery
Not every mattress can bend with an adjustable base — but these can. Every mattress here is built to flex with the head and foot articulation of an adjustable base without damaging the comfort layers, so you can read, relax in Zero-Gravity or elevate your legs with confidence. In fact, over 90% of our mattresses are adjustable-compatible, spanning memory foam, hybrid and pocket-coil constructions from every brand — NM, Sealy, Serta, Beautyrest, Tempur-Pedic, Stearns & Foster and more — at every budget from about $109 to premium. Foam and hybrid models flex most easily, while rigid, thick tight-top innersprings generally don't. Pair any of these with one of our adjustable bases, and every mattress comes with a 365-night sleep trial and free delivery across Canada. • What this means: mattresses built to flex with an adjustable base's head & foot articulation • Over 90% of our mattresses are adjustable-compatible — every brand, every budget ($109+) • Best constructions for adjustable bases: memory foam, hybrid and pocket-coil • What usually won't work: rigid, thick tight-top innersprings that don't bend • Pairs with our adjustable bases (including split-king for independent sides) • Every order: 365-night sleep trial, price-match guarantee & free Canada-wide delivery

NM Mattresses is our in-house brand, offering high-quality, budget-friendly beds tailored for Canadian sleepers — durable components and honest value without compromising comfort or support.

Shop NM across the NM®, Essentials, Cozy, Hi-Loft™, HD+™ Core, Orthopedic and Hospitality lines, in single/twin through king. Built in Canada and the USA with 5- to 25-year manufacturer warranties depending on the line, every NM mattress comes with our 365-night sleep trial and price-match guarantee.

King Extra Firm Edge Support Mattresses Adjustable Bed Compatible Mattresses NM
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Items

  • BEAUTYREST® BeautySleep® 11.5" Extra-Firm Tight Top Mattress - 1 Beautyrest BeautySleep Logo
    • 815 Original Beautyrest® Pocketed Coil®
    • Gel-Infused Fibre Blend
    • AirFeel® Foam
    • Gel Foam + Gel Memory Foam
    • High-Density Foam Encasement
    King $885
    Compare at $2,099
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  • Beautyrest 12.5-inch extra-firm tight-top mattress, flat grey quilted top with teal waves, charcoal sides Beautyrest Mattress Collection Logo
    • 875 Beautyrest® Pocketed Coil Technology
    • Beautyrest® ActiveResponse Memory Foam
    • SurfaceTouch™ Gel Memory Foam
    • Beautyrest® Extra Firm Gel Foam
    • InfiniCool™ TechnologyBeautyrest®
    • Beautyrest® Antimicrobial Fibre Technology
    King $1,034
    Compare at $2,399
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  • CHIROFOAM™ XF 12" Extra-Firm Hybrid Mattress
    BEST IN CLASS BEST SELLING TOP RATED
    Chirofoam XF 12-inch extra-firm hybrid mattress, white damask top, full-height navy diamond-quilted sides Chirofoam Logo
    • Cool Gel Infused Memory Foam
    • Extra Firm Support Chirofoam
    • Pro Lumbar Support
    • Canadian Made 1000 Hi-Loft Pocket Coils
    • 15 Year Warranty
    King In stock for fast delivery $836
    Compare at $1,499
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  • CHIROFOAM™ XF 2.0 - 10" Extra-Firm Memory Foam Mattress - 1 Chirofoam Logo
    • 7″ Optimal High Density Bio-Foam Core
    • 2″ Extra Firm Support Chirofoam
    • Pro Lumbar Support
    • 1″ Cool Gel Memory Foam
    • Cool Touch Performance Cover
    • 15 Year Warranty
    • Made In Canada
    King In stock for fast delivery $906
    Compare at $1,699
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  • CHIROFOAM™ XF 10" Extra-Firm Memory Foam Mattress
    BEST IN CLASS BEST SELLING TOP RATED
    Chirofoam XF 10-inch extra-firm memory foam mattress, white geometric-knit top, pale blue edge, navy sides Chirofoam Logo
    • Cool Gel Infused Memory Foam
    • Extra Firm Support Chirofoam
    • Pro Lumbar Support
    • Body Support Bio Foam Core
    • 15 Year Warranty
    King In stock for fast delivery $954
    Compare at $1,699
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  • National Mattress HD 13-inch extra-firm pillow-top foam mattress, tall black quilted sides, white diamond top NM Logo
    • Extra-Firm High Density Foam Core
    • High-Density Foam Support Layers
    • Bamboo Quilted Top
    • 25 Year Warranty
    • Made In Toronto, Canada
    King In stock for fast delivery $906
    Compare at $1,599
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  • National Mattress 12-inch extra-firm tight-top mattress, white diamond-quilted top with black quilted sides NM Hi-Loft Collection Logo
    • 1000 Hi-Loft Pocket Coil with Foam Encased Perimiter
    • HD High Density Support Foam
    • Bio-Foam natural foam content reduces your carbon footprint
    • 10 Year Warranty
    • Made In Toronto, Canada
    King In stock for fast delivery $698
    Compare at $1,299
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  • Serta Modern Series 10-inch extra-firm gel foam mattress, white geometric cover, navy fabric base Serta Modern Series Memory Foam Mattress Logo
    • 10 Inch Model with Double Layers of Comfort
    • Serta CoolWick Breathable Cover
    • PureComfort Gel Foam with PureComfort Foam Support Core
    • Designed and Built in Canada
    King $765
    Compare at $1,799
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  • SERTA® Perfect Sleeper® 14.5" Extra-Firm Tight Top Mattress - 1 Serta Perfect Sleeper Premium Mattress Logo
    • 1050 3-Zoned Coil System
    • CoolFeel™ Plus Fabric
    • QuiltLoft™ Memory Foam
    • Cool Twist® Gel Memory Foam
    • Serta® Firm Support Foam
    • 10 Year Warranty
    • Made In Canada
    King $1,244
    Compare at $2,899
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  • Serta Classic 11.5-inch extra-firm tight-top mattress, blue-white ombre top, navy floral sides Serta Classic Mattress Logo
    • 800 Edition Custom Support Coil System
    • 3 Zone Body Support
    • Cool Twist® Gel Memory Foam + Serta® Support Gel Foam
    • Serta® Anti-Microbial Fibre Technology
    • Serta® Best Edge® Foam Encasement
    • Designed and Made in Canada
    King $885
    Compare at $2,099
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  • Springwall Chiropractic 14-inch firm euro-top mattress, navy swirl-quilted top, grey mesh sides Springwall Chiropractic Premium Mattress Logo
    • 1800 7-Zoned Chiropractic® Pocket Coils
    • Cold PE Technology Premium Surface Fabric
    • AIRWAYS™ Specialty Foam
    • Graphite Gel PCM Comfort Layers
    • CoreBalance™ Support System with Micro Coils
    King In stock for fast delivery $1,068
    Compare at $2,199
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  • Springwall Comfort Pockets 10.5-inch extra-firm euro-top mattress, black grey lattice top, black quilted sides Springwall Comfort Pockets Mattress Logo
    • 884 Full Perimeter Comfort Pockets® (Pocket Coils)
    • HD Firm Bio Comfort Foam
    • Cool Touch Stretch Knit Sleep Surface
    • Bio Comfort Quilted Stretch knit surface
    • Made In Canada
    King In stock for fast delivery $592
    Compare at $1,299
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How to Choose Within the NM Line

The NM line is our own label, and it covers the whole bed: sprung and all-foam mattresses, box springs, a solid wood platform bedframe, headboards, pillows, sheets and a waterproof protector. Work from the sleep surface outward. The coil models are built on heat-tempered drawn spring steel in Bonnell, pocket coil, foam-encased pocket coil and individually pocketed configurations, and the difference is how they behave: pocketed coils compress one at a time and isolate movement, while a connected coil system shares load for a firmer, more uniform feel. The all-foam models use high-density polyurethane support foam with no springs at all, which removes bounce and noise. Within the line, NM Orthopedic Classic, PLUS and Supreme are the sprung builds, NM Cozy is memory foam, NM HD+ Core is high-density foam, and NM Hi-Loft Elite and NM Essential cover euro top and hybrid feels.

Then come the layers around the mattress. A box spring is not just a spacer, because its profile decides how high you sit: a standard box spring runs about 9 inches deep and a low profile one about 5, so stepping down gains you roughly four inches of clearance rather than half the height. A platform version is thinner again, and NM offers platform, low profile, standard and high profile options, with the depth listed on each. Aim for a finished bed where the top of the mattress lands near your knee as you stand beside it, and ask about split options if your staircase or hallway has a tight turn. Above the mattress, the waterproof protector is the piece most people skip and later regret. What wears a mattress out is mechanical, foam fatigue in the comfort layers and coil set underneath, so a protector is not the thing keeping the bed alive: it is there for hygiene, and for keeping the mattress in the condition a warranty claim depends on. NM pillows include charcoal, copper and lavender infused options alongside shredded memory foam, duck feather, microfiber and wool, so match loft to your sleeping position.

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Coils or All Foam

Pocketed springs isolate motion, connected coils feel firmer and more uniform, and all-foam cores remove bounce and noise entirely.

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Profile Sets Bed Height

Platform, low profile, standard and high profile change the finished height by inches. See how standard and low profile compare.

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Protect It From Day One

A waterproof protector keeps sweat and spills out of the foam, which matters for hygiene and for keeping the mattress in the condition a warranty claim depends on. Our protector guide explains what to look for in a cover.

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Frame and Headboards

The solid wood platform bedframe comes in a natural and a walnut finish, and the George and Layla headboards pair with it. See bedroom essentials.

Frequently Asked Questions About NM Mattresses and Bedding

What is the NM brand?
NM is the National Mattress house label. It spans mattresses in sprung, hybrid and all-foam builds, box springs in several profiles, a solid wood platform bedframe, headboards, pillows, sheets and a waterproof protector. Because it is one line, the sizes are designed to work together, so a mattress, a box spring and a frame from it fit each other without measuring twice.
What is the difference between the NM foam and NM coil mattresses?
The coil models put heat-tempered drawn spring steel under the comfort layers, which gives a springier, more supportive push-back and better airflow through the core. The all-foam models use high-density polyurethane support foam instead, so they run quieter, transfer less movement and contour more closely. Coils suit people who want a firm, responsive surface; foam suits those who want the bed to give way.
Which NM box spring profile should I choose?
Work backwards from the height you want to sit at. A standard box spring runs about 9 inches deep and a low profile one about 5, so stepping down gains you roughly four inches of clearance rather than half the height. A platform version is thinner again, which is the one to pick when the mattress is already tall. The depth is listed on each option, so check it against your mattress before ordering, and ask about split options if your staircase or hallway has a tight turn.
Does an NM foam mattress need a box spring?
Not necessarily. An all-foam mattress needs a flat, evenly supported surface, which a platform bedframe with closely spaced slats already provides. Aim for gaps of about three inches or less, with slats a couple of inches wide. What it must not sit on is a sagging old box spring, or slats spaced far apart, because the foam will bow into the gaps. If your frame has wide slats, a thin platform box spring or a bunkie board bridges them. See slats and box springs.
Is there an NM mattress for a crib?
Yes. The NM Lullaby mattresses are made for crib sizes and are dual sided, with a firmer infant side and a softer toddler side, so one mattress carries a child through both stages. Infant sleep guidance calls for a firm, flat surface with no gap between the mattress and the crib wall, so measure the crib interior before ordering.
Which NM pillow should I choose?
Match the loft to how you sleep. Stomach sleepers need a low, soft pillow so the neck is not pushed back, back sleepers want a medium loft that fills the hollow under the neck, and side sleepers need the most height and firmness to keep the head level with the spine. Our pillow guide compares the fills.

Building a Whole Bed, Not Just Choosing a Mattress?

Our non-commissioned sleep experts can size the frame, the box spring and the sheets to the mattress you pick, in one conversation.

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