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King Adjustable Bed Base Friendly Natural & Organic Mattresses All

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.
Shop adjustable base friendly mattresses from Beautyrest, Serta, Sealy, Tempur-Pedic, Springwall, iComfort, and Stearns & Foster at National Mattress — 169+ models in memory foam, hybrid, latex, eurotop, and tight-top constructions from $59 to $6,640. Every mattress in this collection is manufacturer-verified to flex and articulate with an adjustable base without voiding the warranty. Available in Twin through King sizes with firmness levels from extra firm to plush, all built with CertiPUR-US® certified foams, including Canadian-made options. Free delivery is available, along with a 365-night sleep trial and 5–15 year warranty coverage.
For a cleaner, more eco-conscious sleep, our natural and organic mattresses are built with materials you can feel good about — natural Talalay latex, organic cotton and wool covers, plant-based and soy-derived foams, and recycled fibres, with low-VOC, CertiPUR-US® certified components. They're a great fit if you want fewer synthetic chemicals, more sustainable materials, or a naturally breathable, hypoallergenic feel. You'll find genuinely certified-organic options — like GOTS organic cotton and organic latex from Natura and Evergreen — alongside natural-material and eco-friendly builds from Serta iComfort ECO, Sealy, Beautyrest and our own NM line. Every mattress includes a 365-night sleep trial and free delivery across Canada. • What "natural materials" means: Talalay latex, organic cotton & wool, plant-based/soy foams and recycled fibres • Certified-organic options: GOTS organic cotton and organic latex (Natura, Evergreen) • Eco-friendly builds: Serta iComfort ECO (REPREVE recycled) plus low-VOC, CertiPUR-US® foams • Best for: shoppers who want fewer synthetic chemicals, sustainable materials, or a naturally breathable feel • Looking specifically for latex? See our latex mattresses • Every order: 365-night sleep trial, price-match guarantee & free Canada-wide delivery
King Adjustable Bed Base Friendly Natural & Organic Mattresses All
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Items

  • BEAUTYREST Centennial 13" Tight Top Firm Mattress, black honeycomb-textured top and charcoal quilted sides Beautyrest Centennial Luxury Mattress Logo
    • 1850 T3 Triple Stranded Pocketed Coil® and Micro Coil Technology
    • SurfaceTouch™ Gel Memory Foam
    • Self-Response™ Latex
    • Beautyrest® Gel Support Foam
    • Sleep Climate™ Surface enhanced with cooling yarn
    King $2,529
    Compare at $3,599
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 as soon as Sun, Oct 11
  • Beautyrest Centennial 15.5-inch pillow top plush mattress, black sparkled pillow top with grey sides Beautyrest Centennial Luxury Mattress Logo
    • 1850 T3 Triple Stranded Pocketed Coil® and Micro Coil Technology
    • SurfaceTouch™ Gel Memory Foam
    • Self-Response™ Latex
    • Beautyrest® Gel Memory Foam
    • Beautyrest® Gel Support Foam
    • Sleep Climate™ Surface enhanced with cooling yarn
    King $2,959
    Compare at $4,199
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 as soon as Sun, Oct 11
  • Beautyrest Centennial 15.5-inch pillow top medium-firm mattress, black sparkled pillow top with grey sides Beautyrest Centennial Luxury Mattress Logo
    • 1850 T3 Triple Stranded Pocketed Coil® and Micro Coil Technology
    • SurfaceTouch™ Gel Memory Foam
    • Self-Response™ Latex
    • Beautyrest® Gel Memory Foam
    • Beautyrest® Gel Support Foam
    • Sleep Climate™ Surface enhanced with cooling yarn
    King $2,959
    Compare at $4,199
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 as soon as Sun, Oct 11
  • Beautyrest Centennial 13.5-inch tight top medium-firm mattress, black sparkled top with grey sides Beautyrest Centennial Luxury Mattress Logo
    • 1850 T3 Triple Stranded Pocketed Coil® and Micro Coil Technology
    • SurfaceTouch™ Gel Memory Foam
    • Self-Response™ Latex
    • Beautyrest® Gel Support Foam
    • Sleep Climate™ Surface enhanced with cooling yarn
    King $2,529
    Compare at $3,599
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 as soon as Sun, Oct 11
  • Beautyrest Centennial 14.5-inch medium-firm tight-top mattress, black gold-flecked top, charcoal quilted sides Beautyrest Centennial Luxury Mattress Logo
    • 2850 T3 Triple Stranded Pocketed Coil® and Micro Coil Technology
    • SurfaceTouch™ Gel Memory Foam
    • Self-Response™ Latex
    • Micro Diamond™ Memory Foam
    • Beautyrest® Gel Comfort Foam
    • Sleep Climate™ Surface enhanced with cooling yarn
    King $3,159
    Compare at $4,499
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 as soon as Sun, Oct 11
  • Beautyrest Centennial 16.5-inch medium-firm super-pillow-top mattress, black gold-flecked top, charcoal sides Beautyrest Centennial Luxury Mattress Logo
    • 2850 T3 Triple Stranded Pocketed Coil® and Micro Coil Technology
    • SurfaceTouch™ Gel Memory Foam
    • Self-Response™ Latex
    • Micro Diamond™ Memory Foam
    • Beautyrest® Gel Memory Foam
    • Sleep Climate™ Surface enhanced with cooling yarn
    King $3,599
    Compare at $5,099
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 as soon as Sun, Oct 11
  • Beautyrest Centennial 16.5-inch ultra-plush super-pillow-top mattress, puffy black gold-flecked top Beautyrest Centennial Luxury Mattress Logo
    • 2850 T3 Triple Stranded Pocketed Coil® and Micro Coil Technology
    • SurfaceTouch™ Gel Memory Foam
    • Self-Response™ Latex
    • Micro Diamond™ Memory Foam
    • Beautyrest® Gel Memory Foam
    • Sleep Climate™ Surface enhanced with cooling yarn
    King $3,599
    Compare at $5,099
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 as soon as Sun, Oct 11
  • Evergreen Aspen 14-inch firm euro-top latex mattress, cream quilted top with green piping, cream sides Evergreen Sleep Organic Latex Mattress Collection Logo
    • 1000 Hi-Loft Pocket Coil with Foam Encased Perimeter
    • Organic Latex Comfort Layer
    • Bio-Foam natural foam content support layers
    • Organic Cotton Quilt with Organic Latex and Organic Wool
    • 10 Year Warranty
    • Made In Toronto, Canada
    King $1,099
    Compare at $1,999
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 as soon as Fri, Oct 9
  • Evergreen 100% organic 10-inch firm latex mattress, cream diagonal-quilted tight-top, brown base trim Evergreen Sleep Pure 100% Organic Latex Mattress Collection Logo
    • 100% Certified Natural Organic Latex
    • Global Organic Latex Standard – Certified 100% Natural
    • Eco-Institute – No Fillers or Hazardous Particles
    • Oeko-Tex Standard 100 – No Harmful Substances
    • ABC Research Laboratories – Certified Antimicrobial
    King In stock for fast delivery $2,650
    Compare at $4,899
    Online availability icon In-Stock Only 3 left!
    In-Store availability icon On Display:
    Free delivery availability icon Free delivery to M5H 2N1 as soon as Tomorrow, Sep 29
    Pickup available icon Only Pickup available to
    M5H 2N1
  • Evergreen 100% organic 10-inch medium-firm latex mattress, white diamond-quilted top, brown base trim Evergreen Sleep Pure 100% Organic Latex Mattress Collection Logo
    • 100% Certified Natural Organic Latex
    • Global Organic Latex Standard – Certified 100% Natural
    • Eco-Institute – No Fillers or Hazardous Particles
    • Oeko-Tex Standard 100 – No Harmful Substances
    • ABC Research Laboratories – Certified Antimicrobial
    King In stock for fast delivery $1,979
    Compare at $4,899
    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 29
    Pickup available icon Only Pickup available to
    M5H 2N1
  • Evergreen 12-inch tight-top medium-firm organic latex mattress, white button-tufted top, sage piped border Evergreen Sleep Organic Latex Mattress Collection Logo
    • 1000 Hi-Loft Pocket Coil with Foam Encased Perimeter
    • Organic Latex Comfort Layer
    • Bio-Foam natural foam content support layers
    • Organic Cotton Quilt with Organic Latex and Organic Wool
    • 10 Year Warranty
    • Made In Toronto, Canada
    King $840
    Compare at $1,499
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 as soon as Fri, Oct 9
  • Evergreen 12-inch medium-firm organic latex foam mattress, white button-tufted top, ribbed sides, sage trim Evergreen Sleep Organic Latex Mattress Collection Logo
    • Open Cell Bio Foam Core
    • 4" Organic Latex Comfort Layer
    • 1" Organic Latex Support Panel
    • Organic Cotton Quilt
    • 10 Year Warranty
    • Made In Toronto, Canada
    King $1,575
    Compare at $2,799
    Online availability icon Backorder Available
    In-Store availability icon On Display:
    Estimated delivery icon Estimated free delivery to M5H 2N1 as soon as Fri, Oct 9

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