King Mattresses Compatible with Adjustable Bed Base | Flex‑Friendly Foam, Latex & Hybrid Black All 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.
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.
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.
Shop 200+ mattresses from Serta, Beautyrest, Sealy, Tempur-Pedic, Springwall, and Stearns & Foster at National Mattress — available in Single/Twin through King sizes from $99 to $6,640. Choose from innerspring, euro-top, memory foam, hybrid, and latex constructions in four firmness levels from extra firm to plush. Every mattress is manufactured in Canadian factories using CertiPUR-US® certified foams and ships free across Canada with a 365-night sleep trial, price match guarantee, and manufacturer warranty coverage up to 25 years.
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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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