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 for a standard bed frame, box spring or platform bed rather than an adjustable base — solid, no-flex support for a classic setup. Shopping by feel or build instead? Browse by comfort (plush, medium, firm) or by type (memory foam, hybrid, pocket coil, traditional). Using an adjustable base? See our adjustable-bed-compatible mattresses. Every order includes a 365-night sleep trial and free delivery across Canada.

King Compatible with Adjustable Bed Mattresses for Standard Bed Frames Brands

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All Brands

Our entire selection of name brands.

Stearns & Foster (18)

Tempur-pedic (17)

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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Thousands in Stock

We have over 1,000 mattresses in stock.

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