Firm King Size Mattress Accessories

Firm mattresses give you the most support of our everyday comfort levels — a solid, stable surface that keeps your spine aligned instead of sinking in. Firm is the go-to for back and stomach sleepers, heavier-weight sleepers who need extra support, and anyone looking for orthopedic, back-friendly comfort; side sleepers or those who like a softer feel may prefer our medium or plush options. Choose from tight-top, foam, euro-top and hybrid builds across Sealy, Serta, Beautyrest, Stearns & Foster, iComfort, Tempur-Pedic, Chirofoam and our own NM line — from budget-friendly models at $59 to premium, with free delivery across Canada. • Feel: firm gives a solid, supportive surface with minimal sink-in • Best for: back and stomach sleepers, heavier-weight sleepers, and orthopedic / back-pain support • Consider softer if you sleep on your side or want more cushioning — see our medium or plush options • Constructions: tight-top (most firm beds), foam, euro-top and hybrid • Brands: Sealy, Serta, Beautyrest, Stearns & Foster, iComfort, Tempur-Pedic, Chirofoam, Springwall & NM • Prices: from $59 (budget) to premium — our widest price range • Want the firmest feel? See our extra-firm mattresses
Everything for a king bed (76″ × 80″) in one place. Shop king mattress protectors, sheet sets, box springs, bed frames, pillows and duvets — note that a king box spring is built as two split halves (each 38″ × 80″) so it's easy to move and fits up tight stairwells. Protectors from HealthGuard and Hush, box springs matched to your mattress brand, plus premium bedding, all with free delivery across Canada. • Fits the king mattress: 76″ × 80″ • Mattress protectors — waterproof, breathable and encasement styles • Sheet sets, duvets and pillows in king sizes • Box springs and foundations (a king ships as two split halves) • Bed frames and bases • Brands: HealthGuard, Restguard, Hush, NM, Leggett & Platt, Sealy, Serta, Beautyrest, Tempur-Pedic & more • Accessories from $13 — free Canada-wide delivery

Complete your sleep setup with pillows, toppers, protectors, and more. These mattress accessories enhance comfort and extend mattress life.

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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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