King MLILY® WellFlex Breathable Mattresses Adjustable Bed Base Friendly 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.
The MLILY® WellFlex collection is built on a Flex Support base foam core for adaptive, body-contouring comfort with virtually no motion transfer. Available in firm and plush feels across 12 to 14 inch profiles, these all-foam mattresses are made in the USA and backed by a 10-year warranty with free next-day delivery in Toronto.
Breathable mattresses are built to move air, not trap it. Through ventilated and open-cell foams, breathable knit and Tencel covers, and pocket-coil airflow, they let heat and moisture escape instead of building up under you — so your sleep surface stays fresher, drier and more comfortable through the night. It's a great fit if you sweat at night, live in a humid climate, or just don't like that stuffy, sunk-in feel. You'll find breathable builds across every brand — Sealy, Serta, Beautyrest, iComfort, Tempur-Pedic, Chirofoam and our own NM line — in foam, hybrid and pocket-coil. Sleep especially hot? See our cooling mattresses for active heat-wicking. Every mattress includes a 365-night sleep trial and free delivery across Canada. • What it means: airflow-focused builds that let heat and moisture escape instead of trapping them • How it works: ventilated/open-cell foams, breathable knit & Tencel covers, pocket-coil airflow • The benefit: a fresher, drier, less stuffy sleep surface • Best for: sweaty sleepers, humid climates, or anyone who dislikes a sunk-in, stuffy feel • Sleep hot? See cooling mattresses; want a steady temp? See temperature-regulating • Across every brand and firmness • Every order: 365-night sleep trial, price-match guarantee & free Canada-wide delivery
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.
The MLILY® WellFlex collection is built on a Flex Support base foam core for adaptive, body-contouring comfort with virtually no motion transfer. Available in firm and plush feels across 12 to 14 inch profiles, these all-foam mattresses are made in the USA and backed by a 10-year warranty with free next-day delivery in Toronto.
Breathable mattresses are built to move air, not trap it. Through ventilated and open-cell foams, breathable knit and Tencel covers, and pocket-coil airflow, they let heat and moisture escape instead of building up under you — so your sleep surface stays fresher, drier and more comfortable through the night. It's a great fit if you sweat at night, live in a humid climate, or just don't like that stuffy, sunk-in feel. You'll find breathable builds across every brand — Sealy, Serta, Beautyrest, iComfort, Tempur-Pedic, Chirofoam and our own NM line — in foam, hybrid and pocket-coil. Sleep especially hot? See our cooling mattresses for active heat-wicking. Every mattress includes a 365-night sleep trial and free delivery across Canada. • What it means: airflow-focused builds that let heat and moisture escape instead of trapping them • How it works: ventilated/open-cell foams, breathable knit & Tencel covers, pocket-coil airflow • The benefit: a fresher, drier, less stuffy sleep surface • Best for: sweaty sleepers, humid climates, or anyone who dislikes a sunk-in, stuffy feel • Sleep hot? See cooling mattresses; want a steady temp? See temperature-regulating • Across every brand and firmness • Every order: 365-night sleep trial, price-match guarantee & free Canada-wide delivery
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.
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Express ShippingUpgrade 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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