Boxspring Adjustable Bases Medium Sealy® Mattresses and Accessories

Medium-firmness mattresses — often called medium-firm — sit right between plush and firm, which is why they're the most popular and versatile feel we carry. You get enough cushioning to relieve pressure with enough support to keep your spine aligned, making medium a safe choice for back sleepers, combination sleepers who change positions through the night, and couples who need a compromise between two preferences. Shop medium models from Sealy, Serta, Beautyrest, Stearns & Foster, iComfort and Tempur-Pedic across memory foam, hybrid, euro-top, pillow-top and tight-top builds — with free delivery across Canada. • Feel: medium sits between plush and firm — balanced and the most versatile of our four comfort levels • Also called "medium-firm" — the middle of the firmness scale • Best for: back sleepers, combination sleepers, couples, and most body types • Consider plush if you sleep on your side; firm if you sleep on your stomach or want more support • Constructions: euro-top, tight-top, pillow-top, memory foam and hybrid • Brands: Sealy, Serta, Beautyrest, Stearns & Foster, iComfort, Tempur-Pedic, Springwall & NM • Prices: from $171 to premium

Sealy is a pioneering mattress brand known for its science-backed support and comfort, with over a century of quality craftsmanship behind it.

Shop Sealy across the Essentials, Cocoon™, Posturepedic®, Posturepedic® Plus, Posturepedic® Luxury and Posturepedic® Natural Origins collections, in single/twin through king. Every Sealy we carry is made in Canada with a 5- or 10-year manufacturer warranty, plus our 365-night sleep trial and price-match guarantee.

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How to Choose the Right Sealy Mattress

Most Sealy® support systems are zoned, which means the coil layer is not set to a single firmness from head to foot. A zoned unit varies firmness by position along the bed, and Sealy concentrates the reinforcement in the centre third, where the hips and the small of the back load it hardest. That is the job Sealy gives the Posture Grid® Coil System featuring PostureSense™ Nano Coils. It is worth saying plainly that zoning is not a better surface than a uniform one, only a different one, and that it answers position rather than body weight: a surface that holds one firmness right across is exactly what many innerspring buyers are after. Posture Touch® Pocket Coils take the other route, wrapping each spring so it compresses on its own and follows your outline in smaller increments.

The SealyMAX Core System featuring SealyResponse™ PRO and SolidSupport™ Pocket Coils is the other name to know. Sealy positions it for spinal alignment and pressure relief rather than for one location inside the build, and the mechanism it publishes for SolidSupport is double packing: 117 coils in the centre third, so the busiest band of the bed carries more springs rather than stiffer wire. The SealyResponse™ HD Pocket Coil is a further pocket coil in the same family, and Sealy publishes no wire specification for it, so compare the models it appears in rather than reading anything into the letters. Above the coils two foams do two jobs: memory foam is viscoelastic and softens against body heat to mould around a shoulder, while resilient polyurethane foam springs straight back and suits transition and base layers that must hold their shape rather than cradle. Firmness comes as Firm, Medium and Plush.

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Zoned by Position

A zoned unit varies firmness along the length of the bed rather than responding differently to two body weights. Our zoned lumbar support explainer shows how the zones are laid out.

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Centre Third Reinforced

SolidSupport double packs 117 coils into the centre third, so the band under your hips carries more springs rather than stiffer wire. Sealy positions the SealyMAX Core System for spinal alignment and pressure relief.

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Two Foams, Two Jobs

Memory foam moulds slowly and absorbs movement, while resilient polyurethane rebounds fast and holds structure. Most builds use both, each where its behaviour helps.

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Firmness Choices

Choose between Firm, Medium and Plush. Lie in your usual position for several minutes before judging, because viscoelastic foam is firmest when it is cold and softens as it warms, so a bed reads firmer for the first twenty minutes.

Frequently Asked Questions About Sealy Mattresses

How does a zoned coil system differ from a uniform coil layer?

A zoned unit varies firmness by position along the length of the bed, usually reinforcing the centre third where the hips and lower back load it hardest, while the sections under the shoulders and calves stay softer. A uniform layer holds one firmness right across. Neither is better; they suit different sleepers, and a firm uniform surface is exactly what many people want from an innerspring. Zoning also answers position, not body weight.

What do PostureSense Nano Coils add to the comfort layer?

They are very small springs used within the Posture Grid Coil System, and they sit in the comfort layer rather than in the support unit. Their job is contouring and responsiveness: a small coil recovers faster than foam of the same thickness and leaves air gaps between springs, so the surface follows your outline without feeling dense. The zone reinforcement itself comes from the coil unit below, where Sealy strengthens the centre third.

How do the SealyMAX Core System and the SealyResponse HD Pocket Coil differ?

The SealyMAX Core System featuring SealyResponse PRO and SolidSupport Pocket Coils is the fuller support package, and Sealy positions it for spinal alignment and pressure relief. The published mechanism for SolidSupport is double packing, with 117 coils in the centre third, so that band carries more springs rather than stiffer wire. The SealyResponse HD Pocket Coil is a separate pocket coil variant, and Sealy does not publish a wire specification for it, so compare the models rather than the letters.

Is the polyurethane foam in a Sealy mattress the same thing as memory foam?

No, though memory foam is a type of polyurethane. Standard polyurethane foam is resilient: press it and it springs back at once, which makes it useful for base and transition layers that must keep their shape. Memory foam has viscoelastic additives, so it softens with body heat and returns slowly, giving the contouring and motion absorption people associate with the material.

Which Sealy firmness should I look at if I wake up with a sore lower back?

The usual starting point is support that keeps your hips level with your shoulders, so the lumbar curve is neither propped up nor left unsupported. Back sleepers often do best on Firm or Medium, while side sleepers frequently need Plush so the shoulder can drop. Our firmness and back discomfort guide covers this properly, and persistent pain is worth raising with a clinician.

Does a Sealy mattress need a matching foundation or boxspring?

Any pocket coil mattress performs as designed only on a base that supports it evenly, since unsupported spans let the coil unit flex in ways it was not built to. Sealy offers a matching boxspring so the pairing is sized and built to work together. Our guide to boxsprings and foundations compares the options, and you can browse boxsprings directly.

Want Help Comparing Sealy Support Systems?

Our non-commissioned sleep experts can explain what each coil system changes and which firmness matches how you actually sleep, and you can read the terms of our sleep trial first.

Read the Sealy Guide Try the Mattress Selector

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.