King Split Head Medium Innerspring Adjustable Bed Base Friendly Default Category

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
Innerspring mattresses use a coil support system for a responsive, bouncy feel with strong airflow that sleeps cool. They deliver reliable edge support and a classic "on top of the bed" feel at an accessible price — a fit for back, stomach, and combination sleepers. Compare every innerspring option below.
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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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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