King Adjustable Bed Compatible Mattresses Temperature-Regulating Mattresses Evergreen Mattresses
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.
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
A temperature-regulating mattress works to keep you at a comfortable, balanced temperature all night and all year — not just cooling you down, but adapting as your body and the seasons change so you don't wake up too hot or too cold. These mattresses use heat-responsive and breathable materials — phase-change covers, gel and graphite foams, Tencel and natural fibres, and airflow-promoting coils — to absorb and release warmth as needed. It's ideal if you run hot and cold, share a bed with a partner who sleeps at a different temperature, or just want consistent comfort through every season. You'll find temperature-regulating builds across every brand — Sealy, Serta, Beautyrest, iComfort, Tempur-Pedic, Chirofoam and our own NM line. Sleep hot specifically? See our cooling mattresses. Every mattress includes a 365-night sleep trial and free delivery across Canada. • What it does: holds a balanced, neutral temperature — adapts so you're not too hot or too cold • How it works: phase-change covers, gel & graphite foams, Tencel/natural fibres and breathable coil airflow • Best for: people who run hot and cold, couples with different sleep temperatures, and year-round comfort • Cooling vs regulating: cooling sleeps cold (for hot sleepers); regulating holds a steady, balanced temp • Across every brand and firmness • 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
A temperature-regulating mattress works to keep you at a comfortable, balanced temperature all night and all year — not just cooling you down, but adapting as your body and the seasons change so you don't wake up too hot or too cold. These mattresses use heat-responsive and breathable materials — phase-change covers, gel and graphite foams, Tencel and natural fibres, and airflow-promoting coils — to absorb and release warmth as needed. It's ideal if you run hot and cold, share a bed with a partner who sleeps at a different temperature, or just want consistent comfort through every season. You'll find temperature-regulating builds across every brand — Sealy, Serta, Beautyrest, iComfort, Tempur-Pedic, Chirofoam and our own NM line. Sleep hot specifically? See our cooling mattresses. Every mattress includes a 365-night sleep trial and free delivery across Canada. • What it does: holds a balanced, neutral temperature — adapts so you're not too hot or too cold • How it works: phase-change covers, gel & graphite foams, Tencel/natural fibres and breathable coil airflow • Best for: people who run hot and cold, couples with different sleep temperatures, and year-round comfort • Cooling vs regulating: cooling sleeps cold (for hot sleepers); regulating holds a steady, balanced temp • Across every brand and firmness • Every order: 365-night sleep trial, price-match guarantee & free Canada-wide delivery
Evergreen offers natural and organic latex mattresses that combine eco-friendly materials with ergonomic design. Handmade in Canada, Evergreen beds use certified organic latex, cotton, and wool to deliver safe, comfortable, and supportive sleep for health-conscious Canadian shoppers.
Shop 200+ mattresses from Serta, Beautyrest, Sealy, Tempur-Pedic, Springwall, and Stearns & Foster at National Mattress — available in Single/Twin through King sizes from $99 to $6,640. Choose from innerspring, euro-top, memory foam, hybrid, and latex constructions in four firmness levels from extra firm to plush. Every mattress is manufactured in Canadian factories using CertiPUR-US® certified foams and ships free across Canada with a 365-night sleep trial, price match guarantee, and manufacturer warranty coverage up to 25 years.
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OPEN BAG - EVERGREEN™ 14" Euro-Top Firm Organic Latex Mattress - King
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OPEN BAG - EVERGREEN™ 100% Certified Organic 10" Firm Latex Mattress - King
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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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