King Medium Back Sleeper Serta Modern Series – Gel Foam Cooling Mattresses 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.
Medium mattresses balance cushioning and support — soft enough to relieve pressure, firm enough to keep your spine aligned. This medium-firm feel is the most universally comfortable choice, suiting combination sleepers, couples with different preferences, and most back and side sleepers. Compare every medium option below by brand and profile.
Back sleepers do best on a mattress that supports the lower back while gently following the spine's natural curve — typically a medium to medium-firm feel. The options below balance support and pressure relief for back sleepers. Compare them by brand, feel, and profile.
Serta Modern Series mattresses deliver cutting-edge comfort at a great price point, featuring gel-infused memory foams and a convenient mattress-in-a-box design – all proudly crafted in Canada for today’s lifestyle.
Medium mattresses balance cushioning and support — soft enough to relieve pressure, firm enough to keep your spine aligned. This medium-firm feel is the most universally comfortable choice, suiting combination sleepers, couples with different preferences, and most back and side sleepers. Compare every medium option below by brand and profile.
Back sleepers do best on a mattress that supports the lower back while gently following the spine's natural curve — typically a medium to medium-firm feel. The options below balance support and pressure relief for back sleepers. Compare them by brand, feel, and profile.
Serta Modern Series mattresses deliver cutting-edge comfort at a great price point, featuring gel-infused memory foams and a convenient mattress-in-a-box design – all proudly crafted in Canada for today’s lifestyle.
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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