King Extra Firm Mattresses Compatible with Adjustable Bed Base | Flex‑Friendly Foam, Latex & Hybrid Mattresses with Edge Support | Stable, Full‑Edge Comfort Yes Springwall Mattresses
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.
Extra firm mattresses deliver the most supportive, no-sink surface we carry — maximum spinal support with the least give. They suit stomach sleepers, heavier bodies, and anyone with back concerns who needs a hard, flat feel. Compare every extra firm option below to find the right fit.
These mattresses are built to flex with adjustable bed bases — bending smoothly at the head and foot without damage — so you can raise, recline, and find your ideal position. Compare every adjustable-base-compatible option below by brand, type, and feel.
Edge-support mattresses use reinforced perimeters so you can sleep right to the edge without roll-off and get firm support when sitting on the side — ideal for couples maximizing space. Compare every edge-support option below by brand, type, and feel.
Extra firm mattresses deliver the most supportive, no-sink surface we carry — maximum spinal support with the least give. They suit stomach sleepers, heavier bodies, and anyone with back concerns who needs a hard, flat feel. Compare every extra firm option below to find the right fit.
These mattresses are built to flex with adjustable bed bases — bending smoothly at the head and foot without damage — so you can raise, recline, and find your ideal position. Compare every adjustable-base-compatible option below by brand, type, and feel.
Edge-support mattresses use reinforced perimeters so you can sleep right to the edge without roll-off and get firm support when sitting on the side — ideal for couples maximizing space. Compare every edge-support option below by brand, type, and feel.
Springwall is a proudly Canadian mattress manufacturer with a heritage of quality and innovation since 1949. As the only 100% Canadian-owned national mattress brand, Springwall offers trusted comfort engineered for the needs of Canadian sleepers.
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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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