King Medium Adjustable Bed Base Friendly Breathable Mattresses Grey 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.
Medium-firmness mattresses — often called medium-firm — sit right between plush and firm, which is why they're the most popular and versatile feel we carry. You get enough cushioning to relieve pressure with enough support to keep your spine aligned, making medium a safe choice for back sleepers, combination sleepers who change positions through the night, and couples who need a compromise between two preferences. Shop medium models from Sealy, Serta, Beautyrest, Stearns & Foster, iComfort and Tempur-Pedic across memory foam, hybrid, euro-top, pillow-top and tight-top builds — with free delivery across Canada. • Feel: medium sits between plush and firm — balanced and the most versatile of our four comfort levels • Also called "medium-firm" — the middle of the firmness scale • Best for: back sleepers, combination sleepers, couples, and most body types • Consider plush if you sleep on your side; firm if you sleep on your stomach or want more support • Constructions: euro-top, tight-top, pillow-top, memory foam and hybrid • Brands: Sealy, Serta, Beautyrest, Stearns & Foster, iComfort, Tempur-Pedic, Springwall & NM • Prices: from $171 to premium
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.
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
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.
Medium-firmness mattresses — often called medium-firm — sit right between plush and firm, which is why they're the most popular and versatile feel we carry. You get enough cushioning to relieve pressure with enough support to keep your spine aligned, making medium a safe choice for back sleepers, combination sleepers who change positions through the night, and couples who need a compromise between two preferences. Shop medium models from Sealy, Serta, Beautyrest, Stearns & Foster, iComfort and Tempur-Pedic across memory foam, hybrid, euro-top, pillow-top and tight-top builds — with free delivery across Canada. • Feel: medium sits between plush and firm — balanced and the most versatile of our four comfort levels • Also called "medium-firm" — the middle of the firmness scale • Best for: back sleepers, combination sleepers, couples, and most body types • Consider plush if you sleep on your side; firm if you sleep on your stomach or want more support • Constructions: euro-top, tight-top, pillow-top, memory foam and hybrid • Brands: Sealy, Serta, Beautyrest, Stearns & Foster, iComfort, Tempur-Pedic, Springwall & NM • Prices: from $171 to premium
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.
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
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.
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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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