King Medium Sustainable Mattresses Compatible with Adjustable Bed Default Category
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
Sleep a little greener with our sustainable mattresses — built to reduce their environmental footprint through recycled and responsibly sourced materials. You'll find covers made from recycled fibres like REPREVE® (spun from recycled plastic bottles) and Seaqual™ ocean-recovered plastics, plant-based and soy-derived foams, and natural fibres, on models such as the Serta iComfort ECO and Beautyrest Harmony, plus eco-conscious builds from Sealy, Evergreen and our own NM line. If lowering your impact matters as much as your comfort, start here. Looking for natural latex, organic cotton or non-toxic materials specifically? See our natural & organic mattresses. Every mattress includes a 365-night sleep trial and free delivery across Canada. • What "sustainable" means here: recycled and responsibly sourced materials that lower the environmental footprint • Recycled materials: REPREVE® (recycled plastic bottles) and Seaqual™ ocean-recovered plastics • Also: plant-based/soy foams and natural fibres, with low-VOC CertiPUR-US® components • Featured eco lines: Serta iComfort ECO, Beautyrest Harmony, plus Sealy, Evergreen & NM • Want natural latex or organic cotton specifically? See our natural & organic mattresses • Every order: 365-night sleep trial, price-match guarantee & free Canada-wide delivery
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
Sleep a little greener with our sustainable mattresses — built to reduce their environmental footprint through recycled and responsibly sourced materials. You'll find covers made from recycled fibres like REPREVE® (spun from recycled plastic bottles) and Seaqual™ ocean-recovered plastics, plant-based and soy-derived foams, and natural fibres, on models such as the Serta iComfort ECO and Beautyrest Harmony, plus eco-conscious builds from Sealy, Evergreen and our own NM line. If lowering your impact matters as much as your comfort, start here. Looking for natural latex, organic cotton or non-toxic materials specifically? See our natural & organic mattresses. Every mattress includes a 365-night sleep trial and free delivery across Canada. • What "sustainable" means here: recycled and responsibly sourced materials that lower the environmental footprint • Recycled materials: REPREVE® (recycled plastic bottles) and Seaqual™ ocean-recovered plastics • Also: plant-based/soy foams and natural fibres, with low-VOC CertiPUR-US® components • Featured eco lines: Serta iComfort ECO, Beautyrest Harmony, plus Sealy, Evergreen & NM • Want natural latex or organic cotton specifically? See our natural & organic mattresses • Every order: 365-night sleep trial, price-match guarantee & free Canada-wide delivery
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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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