NM® Springwall® Marshall® Sealy® Serta® King Split Mattress Accessories
NM mattresses are National Mattress's own line — quality construction at honest, direct prices across firmness levels and builds. Compare every option below by feel, size, and price.
Springwall is a proudly Canadian-made brand known for chiropractic-minded support and durable, value-driven construction. Compare every option below by feel, size, and price.
Marshall® is a Canadian name in handcrafted, pocketed-coil sleep. Each Marshall mattress is built in Canada on an 842 tempered pocketed-coil system with high-density encased edge support, spanning the Crafted and Assured series in medium, firm and plush feels, plus matching boxsprings to complete your set. Backed by a 10-year warranty and free next-day delivery in Toronto.
Sealy mattresses are engineered for dependable, body-aligning support — many featuring Posturepedic Technology that reinforces the centre third where you need it most. Compare every option below by feel, size, and price.
Serta mattresses balance comfort and support with cooling-gel foams and proven coil systems, from a name trusted in Canadian bedrooms for decades. Compare every option below by feel, size, and price.
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
Springwall is a proudly Canadian-made brand known for chiropractic-minded support and durable, value-driven construction. Compare every option below by feel, size, and price.
Marshall® is a Canadian name in handcrafted, pocketed-coil sleep. Each Marshall mattress is built in Canada on an 842 tempered pocketed-coil system with high-density encased edge support, spanning the Crafted and Assured series in medium, firm and plush feels, plus matching boxsprings to complete your set. Backed by a 10-year warranty and free next-day delivery in Toronto.
Sealy mattresses are engineered for dependable, body-aligning support — many featuring Posturepedic Technology that reinforces the centre third where you need it most. Compare every option below by feel, size, and price.
Serta mattresses balance comfort and support with cooling-gel foams and proven coil systems, from a name trusted in Canadian bedrooms for decades. Compare every option below by feel, size, and price.
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
Complete your sleep setup with pillows, toppers, protectors, and more. These mattress accessories enhance comfort and extend mattress life.
Loading recommendations...
Navigating through the elements of the carousel is possible using the tab key. You can skip the carousel or go straight to carousel navigation using the skip links. ![]()
![]()
![In stock for fast delivery]()
SOLD OUT ![In stock for fast delivery]()
SOLD OUT ![Online availability icon]()
Only left! ![In-Store availability icon]()
On Display: ![Estimated delivery icon]()
on ![]()
as soon as ![Pickup available icon]()
Only Pickup available to
Compare at
Compare at
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.
Filters
Loading recommendations...
Navigating through the elements of the carousel is possible using the tab key. You can skip the carousel or go straight to carousel navigation using the skip links. ![]()
![]()
![In stock for fast delivery]()
SOLD OUT ![In stock for fast delivery]()
SOLD OUT ![Online availability icon]()
Only left! ![In-Store availability icon]()
On Display: ![Estimated delivery icon]()
on ![]()
as soon as ![Pickup available icon]()
Only Pickup available to
Compare at
Compare at
