King Extra Firm Luxury Mattresses Adjustable Bed Compatible Mattresses Compatible with Adjustable Bed Mattress Selector

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
Luxury is the top of our lineup — the finest mattresses we carry, built with the most advanced comfort technology and the premium materials money can buy. This is where you'll find Tempur-Pedic's signature TEMPUR® memory foam (Tempur-LuxeAlign and ProAlign), Serta's iComfort PRO all-latex and europillowtop beds, and Stearns & Foster's hand-finished Lux Estate, alongside other premium flagships from Beautyrest and Sealy. Expect deeper pressure relief, superior motion isolation and exceptional durability, in plush, medium and firm. Luxury mattresses range from about $819 to $6,999, and every one includes a 365-night sleep trial, price-match guarantee and free delivery across Canada. • What "luxury" means: our finest, flagship mattresses — the most advanced comfort tech and premium materials • Featured flagships: Tempur-Pedic (LuxeAlign & ProAlign), Serta iComfort PRO, Stearns & Foster Lux Estate • Premium builds: TEMPUR® memory foam, all-latex, thick europillowtop and hybrid • What you get: deeper pressure relief, superior motion isolation and exceptional durability • Price range: about $819 to $6,999 • On a budget? See our great-value or premium mattresses • 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
King Extra Firm Luxury Mattresses Adjustable Bed Compatible Mattresses Compatible with Adjustable Bed Mattress Selector

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Upgrade your sleep at National Mattress

Discover a mattress that transforms your sleep into a truly rejuvenating experience. We offer a wide variety of options to suit every sleep style and preference, ensuring a better night's sleep.

Why Choose Us?

  • Variety: From plush to firm, we have options for every body type and sleep style.
  • Quality: Trusted brands and top-notch materials for long-lasting comfort.
  • Sleep Trials & Warranties: Enjoy peace of mind with flexible trials and warranties.
  • Expert Advice: Get personalized recommendations from our sleep specialists.

Mattress Selection Includes

  • Memory Foam: Contours to your body for personalized comfort and pressure relief.
  • Hybrid: Combines responsive springs with foam for balanced support and comfort.
  • Innerspring: Provides firm support, bounce, and cooling airflow.
  • Latex: Hypoallergenic, eco-friendly, and exceptionally comfortable.
  • Adjustable Beds: Customize your sleep position for optimal comfort.
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