Boxspring Bedding/Sheets Premium King Split All
Premium is the sweet spot between everyday value and luxury — name-brand mattresses with better materials, thicker comfort layers and more advanced support, without the flagship price tag. This is where you'll find recognizable comfort lines like Sealy Posturepedic Plus, Serta Perfect Sleeper and Perfect Day, Beautyrest Harmony, Chirofoam memory foam and Springwall Chiropractic — in euro-top, pillow-top, hybrid, memory foam and even organic latex builds, across every firmness from plush to extra firm. Most premium mattresses run from about $400 to $1,400. Every one includes a 365-night sleep trial, price-match guarantee and free delivery across Canada. • What "premium" means: name-brand comfort and upgraded materials — a step up from value, below the luxury flagships • Featured lines: Sealy Posturepedic Plus, Serta Perfect Sleeper & Perfect Day, Beautyrest Harmony, Chirofoam, Springwall Chiropractic • Builds: euro-top, pillow-top, hybrid, memory foam and organic latex • Every firmness from plush to extra firm • Typically about $400 to $1,400 • Looking higher or lower? See our luxury or great-value mattresses • Every order: 365-night sleep trial, price-match guarantee & free Canada-wide delivery
A king box spring is almost always built as two split halves (each 38″ × 80″ — the same footprint as a Twin XL) that sit side by side under your king mattress (76″ × 80″). The split design makes a large king foundation easy to deliver, carry up stairs and set up, and it's exactly what a split-king adjustable base needs so each side can raise and lower independently. Shop split king box springs and foundations matched to Sealy, Serta, Beautyrest, Simmons, Stearns & Foster and more — free delivery across Canada. • What it is: a king box spring built as two 38″ × 80″ halves (each a Twin XL footprint) • Together they support a standard king mattress (76″ × 80″) • Easier to deliver and carry up stairs than a one-piece foundation • Required for split-king adjustable bases (each side adjusts independently) • Brands: Sealy, Serta, Beautyrest, Simmons, Stearns & Foster, Springwall, Galaxy & NM • From $176 — free Canada-wide delivery
A king box spring is almost always built as two split halves (each 38″ × 80″ — the same footprint as a Twin XL) that sit side by side under your king mattress (76″ × 80″). The split design makes a large king foundation easy to deliver, carry up stairs and set up, and it's exactly what a split-king adjustable base needs so each side can raise and lower independently. Shop split king box springs and foundations matched to Sealy, Serta, Beautyrest, Simmons, Stearns & Foster and more — free delivery across Canada. • What it is: a king box spring built as two 38″ × 80″ halves (each a Twin XL footprint) • Together they support a standard king mattress (76″ × 80″) • Easier to deliver and carry up stairs than a one-piece foundation • Required for split-king adjustable bases (each side adjusts independently) • Brands: Sealy, Serta, Beautyrest, Simmons, Stearns & Foster, Springwall, Galaxy & NM • From $176 — free Canada-wide delivery
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Express ShippingUpgrade 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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