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OPEN BAG - SERTA® Modern Series™ 10" Extra-Firm Gel Foam Mattress - King

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.

Top Features

Add To Compare

– 10 Inch Model with Double Layers of Comfort

– Serta CoolWick Breathable Cover

– PureComfort Gel Foam with PureComfort Foam Support Core

– Designed and Built in Canada

Our Price: $663.00

$530.40

Retail Price $1,399.00

Out of stock

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Our Guarantees

+ Learn More About Open Bag items

+ Full Manufacturer’s Warranty

+ Price Match Guarantee

+ Made in Canada

➜ Not sure which mattress is best for you? Try our MATTRESS SELECTOR to help you decide!

➜ See our REVIEWS from verified customers!

OPEN BAG - SERTA® Modern Series™ 10" Extra-Firm Gel Foam Mattress - King

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Memory Foam, Foam Core/No Coils, King Size Mattress, Serta Mattress Sale, Buy in Toronto, Mississauga, Markham or Online-1

Memory Foam, Foam Core/No Coils, King Size Mattress, Serta Mattress Sale, Buy in Toronto, Mississauga, Markham or Online-2

Memory Foam, Foam Core/No Coils, King Size Mattress, Serta Mattress Sale, Buy in Toronto, Mississauga, Markham or Online-3

Memory Foam, Foam Core/No Coils, King Size Mattress, Serta Mattress Sale, Buy in Toronto, Mississauga, Markham or Online-4

Memory Foam, Foam Core/No Coils, King Size Mattress, Serta Mattress Sale, Buy in Toronto, Mississauga, Markham or Online-5

Memory Foam, Foam Core/No Coils, King Size Mattress, Serta Mattress Sale, Buy in Toronto, Mississauga, Markham or Online-6

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Style	Memory Foam, Foam Core/No Coils
Firmness	Extra Firm
Coil Count	N/A
Coil Type	N/A
Core Type	PureComfort™ Foam Support Core
Core Density	1.8 lb/ft³
Height	10 Inches

Collection	Serta® Modern Series™
Model	Modern Boost XF - King
Warranty	10 Year Warranty
Condition	Open Bag Item - Clearance

Comfort Scale

Soft
Medium
Firm
Extra Firm

Comfort IQ™: This mattress firmness is accurate and comparable to other extra-firm mattresses. (10/10)

Recommended For: Back Sleepers, Stomach Sleepers

Our Guarantees

+ Learn More About Open Bag items

+ Full Manufacturer’s Warranty

+ Price Match Guarantee

+ Made in Canada

➜ Not sure which mattress is best for you? Try our MATTRESS SELECTOR to help you decide!

➜ See our REVIEWS from verified customers!

Description

Serta Modern Boost XF 10" Extra-firm Gel Foam Mattress - King: Discover Unmatched Support and Comfort Every Night

Elevate your sleep sanctuary with the Serta Modern Boost XF mattress, expertly designed for those who crave an extra-firm sleeping surface. This king-size mattress combines innovative PureComfort Gel Foam with a strong Foam Support Core to provide a luxurious yet supportive resting experience. Embrace the joy of waking up invigorated with unparalleled comfort and rejuvenation!

Key Features

10-Inch Profile: A harmonious blend of height and durability, featuring dual comfort layers that enhance your overall sleeping experience.
Breathable Serta CoolWick Cover: This state-of-the-art fabric effectively manages moisture, ensuring a refreshingly dry sleep throughout the night.
Cooling PureComfort Gel Foam: Infused with cooling properties, this innovative foam promotes a serene temperature, making your sleep airy and calming.
Robust Support Core: Engineered with the PureComfort Foam Support Core, this mattress ensures optimal body alignment and enduring support for years to come.

Benefits

Extra Firm Texture: Perfect for those who enjoy a straighter sleep surface, it helps improve spine alignment and alleviates pressure for a more restorative night.
Year-Round Adaptability: The cooling elements of the PureComfort Gel Foam create a consistent sleep environment, ideal for all seasons.
Safety Certification: Feel confident sleeping on this mattress, constructed with CertiPUR-US certified foams that adhere to the highest safety and environmental standards.

Ideal For

The Serta Modern Boost XF mattress is crafted for singles and couples who value a firmer support system. It's tailored to accommodate a variety of sleeping styles and body types. With construction rooted in local craftsmanship, this mattress is also a proud choice for residents across Canada.

Details

Dimensions: 76″ x 80″ (inches) | 193cm x 203cm (centimeters)
Height: 10 Inches
Firmness Level: Extra Firm
Warranty: Full Manufacturer's Warranty included
Guarantees: Enjoy Free next day delivery, a Price match guarantee, and a 100 night sleep trial

Indulge in the exquisite comfort of the Serta Modern Boost XF mattress, where state-of-the-art engineering meets luxurious sleeping solutions. Whether you are a devoted firm mattress aficionado or exploring ways to improve your sleep quality, this mattress guarantees a nightly experience of regeneration and relaxation. Say farewell to restless nights, as this meticulously crafted design supports you in attaining blissful slumber night after night!

Specifications

More Information
Mattress Size	King
Mattress Type	Memory Foam , Foam Core/No Coils
Features	Cooling Technology , Temperature Regulating, Breathable, Low Motion Transfer, Pressure Point Relief, Edge Support, Moisture Wicking, Compatible with Adjustable Bed Base
Trending & Offers	Clearance , Limited Stock
Firmness	Extra Firm
Core Type	PureComfort™ Foam Support Core
Core Density	1.8 lb/ft³
Core Material	Polyurethane (polyfoam)
Brands	Serta
Price Range	Great Value
Model	Modern Boost XF - King
Collection	Serta® Modern Series™
Condition	Open Bag Item - Clearance
Warranty	10 Year Warranty
Sleep Position	Back Sleepers, Stomach Sleepers
Cover Material	Serta CoolWick™ Breathable Cover
Colour	Blue
Quilt	Non-quilted stretch-knit cover
Comfort Layers	PureComfort™ Gel Foam
Support Layers	Serta® Support Foam
Mattress Core	PureComfort™ Foam Support Core
Mattress Height in Inches	10 .00 Inches
Additional Features	Advanced Cooling Construction
Certifications	CertiPUR-US® certified foams.
Compatible With Adjustable Beds	Yes
Vented	No
Removable Cover	No
Handles	No
Care Instruction	Spot clean. Mattress protector recommended.
Country of Origin	Canada
Manufacturer Contact Information	https://www.sertacanada.com
King Size Dimensions	76″ x 80″ (inches) – 193cm x 203cm (centimeters)
Custom Sizes Available	No
Product Length (inches)	80 in
Product Width (inches)	76 in
Product Height (inches)	10 in
Product Weight (lb)	120.800000
Product Length (cm)	203.2 cm
Product Width (cm)	193 cm
Product Height (cm)	25.4 cm
Product Weight (kg)	54.8 kg
Product Barcode	0690214113698
Product Code	850002148-1060
Product Model Code	SERTA-MODERNBOOSTXF
Product SKU	SERTA-MODERNBOOSTXF-KING-OPENBAG
Product Category	Mattress
Product Sub Category Tier	Value
Product Type	Mattress - Foam Core
Product Sub Type	Memory Foam

More Info.

Serta is proud to be the manufacturer of the World’s Best Mattress™. Their commitment to quality has made them a leader in the industry, and they look forward to helping you find the right mattress so you can get a better night’s sleep for years to come.

Visit our Mississauga mattress outlet or Toronto mattress outlet to view Serta mattresses on sale and special deals and outlet pricing offers! All mattresses are brand new, sealed, with full manufacturer’s warranty serviced by National Mattress Outlet.

For more than 80 years, Serta has been making consistent investments into the highest quality and most innovative features to ensure that every mattress set we manufacture delivers superior comfort and support. Throughout its history, Serta has been an industry leader, offering many product “firsts” – including the world’s first-ever “tuftless” mattress. Today, Serta is proud to offer a variety of exclusive features including our patented Advanced Comfort Quilt® and Continuous Support® Innerspring.

For more information please visit www.sertacanada.com.

Delivery Options

Greater Toronto Area and Ontario Delivery Map

What’s Included

We offer FREE DELIVERY to all major cities in Ontario and the surrounding area on orders over $199. A delivery surcharge of $45 applies to orders under $199.

Select your delivery date at checkout (if applicable) and add any special instructions in the order comments (e.g., “Ring Buzzer #1234”). If a date isn’t shown or selected at checkout, you’ll receive an email with scheduling options. Day‑of, you’ll get a text and email with a 2‑hour window and live tracking. Estimates apply to in‑stock items; rural or weather‑affected addresses may require extra time.

Greater Toronto Area and Ontario Free Mattress Delivery Map

Ontario Local Delivery Areas

Next‑day available

Halton Region

Burlington • Oakville • Milton • Georgetown • Halton Hills

Next‑day available

Peel Region

Mississauga • Brampton • Caledon

Next‑day available

City of Toronto

York • Including Downtown Core

Next‑day available

York Region

Vaughan • King • Richmond Hill • North York • Aurora • Newmarket • Markham • Scarborough

Next‑day available

Durham Region

Pickering • Ajax • Whitby • Oshawa • Whitchurch‑Stouffville

Next‑day available

Waterloo Region

Guelph • Kitchener • Cambridge • Waterloo

Next‑day available

Hamilton

Including Dundas • Grimsby • Stoney Creek • Ancaster

1–3 days on average

Niagara

Niagara Falls • Niagara‑on‑the‑Lake • St. Catharines • Thorold • Welland

Next‑day & 1–3 days

Simcoe Region

Barrie • Innisfil • Orillia • Midland • Collingwood • Bradford • Washago and more

1–3 days on average

Northern &
Eastern Ontario

Cobourg • Peterborough • Kawartha Lakes • Minden • Haliburton • Port Perry • Bowmanville and more

1–3 days on average

Western Ontario

London • Stratford • Woodstock • Brantford • Grand Bend • Port Elgin • Tobermory and more

Need delivery outside the GTA?

We also ship to all provinces in Canada at competitive rates (territories excluded). Enter your postal code at the top of the website to see what’s available.

Ready to Sleep Better?

Shop online 24/7 or visit any National Mattress location across Ontario. Spend $199+ and relax—your new mattress will arrive quickly and free of charge locally, or ship fast across Canada.

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Frequently Asked Questions

Where does National Mattress offer free local delivery?

We offer FREE local delivery to major cities across Ontario on orders of $199+. Check the region cards above for specific cities.

Do you ship mattresses across Canada?

Yes. We ship select roll‑packed mattresses to all provinces (YT, NT, NU excluded). Transit times range from 1–2 days in ON & QC to 3–4 days in BC and NL after shipping.

Is next‑day delivery available in the GTA?

Yes. FREE next‑day local delivery is available in many GTA and surrounding areas, subject to inventory and cutoff times.

What if my Ontario local order total is under $199?

A $45 delivery surcharge applies to orders under $199.

How do I schedule or change my delivery date?

Select a date at checkout. If a chosen date isn’t available, you’ll receive an email proposing an alternative—simply reply to reschedule. In‑store purchases can be scheduled at the time of sale.

Will I get tracking updates?

Yes. Local deliveries include day‑of text/e‑mail with a 2‑hour window plus live GPS tracking. Canada‑wide shipments include a courier tracking number once picked up.

Do you deliver to Yukon, Nunavut, or the Northwest Territories?

No. We currently do not deliver to YT, NU, or NT.

Need help? 1‑800‑631‑4883 [email protected]

Product Questions (32)

Customer Questions

What materials give this mattress its extra-firm feel?

This mattress uses a combination of extra-firm comfort foams and a robust support core such as high-density base foam or firm, high-gauge pocketed coils to create its extra-firm feel. The design limits sink-in and keeps the surface very flat; see the...

What type of mattress protector should I use that wont feel hot or noisy?

Look for waterproof protectors made with soft, breathable fabrics and a quiet backing layer. Modern protectors are often designed to feel like a regular sheet while still blocking liquids and minimizing crinkling sounds when you move at night.

Is this memory foam mattress suitable for couples with different comfort preferences?

This memory foam mattress is designed with a balanced comfort and support profile that many sleepers find comfortable, but it may still favor certain preferences. Review the firmness level, motion isolation information, and customer feedback to see ...

If something goes wrong, do I contact you or the manufacturer for a warranty claim?

If you experience an issue that you believe is warranty-related, start by contacting the retailer where you purchased the mattress. They can guide you through the correct process, which may involve working directly with the manufacturer or submitting...

Is there a weight limit for this king mattress?

Most king mattresses list a recommended weight range or are designed to support typical single sleepers or couples. Check the product specifications or warranty details for any stated weight limits to ensure the mattress is a good match for the intended...

Does this mattress have strong edge support?

This extra-firm mattress includes edge-support features such as reinforced coils or denser foam rails to help reduce roll-off and make it comfortable to sit or sleep near the edge. Check the product description for more details on how the edges are ...

How does this extra-firm model compare in feel to your firm and medium-firm models?

This extra-firm mattress is noticeably harder and flatter at the surface than our firm and medium-firm options. If you want maximum support with minimal cushioning, choose this extra-firm model; if you prefer some contouring and softer pressure relief...

Is this king mattress good for side sleepers?

Side sleepers usually prefer a mattress that relieves pressure at the shoulders and hips while keeping the spine aligned. Look for king mattresses described as medium or medium-soft with comfort layers that contour to the body and cushion key pressure...

Is this foam mattress better suited for a primary bedroom or a guest room?

This mattress offers a specific combination of comfort, support, and durability that may make it ideal for nightly use in a primary bedroom. Review the firmness, build quality, and price point to decide where it best fits in your home.

Do I need a mattress protector for this memory foam mattress?

A mattress protector is strongly recommended for any memory foam mattress. It helps keep the surface clean, protects against spills and allergens, and can extend the life of the mattress by preventing moisture and debris from breaking down the foam ...

Has this memory foam mattress been tested for emissions or safety standards?

This memory foam mattress is manufactured to meet applicable safety and flammability regulations, and its foams may be tested for content and emissions. Check the product details for specific information on any standards, certifications, or safety testing...

Is this mattress suitable for my sleep position and body type?

This pressure-relief mattress has a particular firmness and layering profile designed for certain sleep positions and weight ranges. Check the comfort description and any recommended sleeper profiles in the product details to ensure it provides both...

How should I care for and clean this mattress?

Use a mattress protector to guard against spills and stains, vacuum the surface occasionally to remove dust, and follow the manufacturer's spot-cleaning instructions for any accidents. Avoid harsh chemicals or saturating the mattress with liquid, and...

Is this foam mattress suitable for couples with different comfort preferences?

This foam mattress is designed with a balanced comfort and support profile that many sleepers find comfortable, but it may still favor certain preferences. Review the firmness rating, motion isolation information, and customer feedback to see how well...

Will this mattress hold its shape and pressure-relieving feel over time?

This pressure-relief mattress is built with comfort and support materials selected to maintain their feel under normal use. Review the durability details, foam densities or coil specifications, and care recommendations in the product description to ...

Is this Serta mattress better for a primary bedroom or a secondary/guest room?

Is this 10 inch mattress all foam, hybrid, or innerspring?

This mattress uses the construction described on the product page, for example all foam, hybrid, or innerspring. Review the materials section to see details about the support core, comfort layers, and cover so you know what type of feel and performance...

Is this 10 inch mattress compatible with an adjustable base?

Many 10 inch foam and hybrid mattresses are flexible enough to be used on adjustable bases. Check the product description for specific notes about adjustable base compatibility and follow the manufacturer's instructions to ensure correct use and...

Will this 10 inch mattress feel different from my current thinner mattress?

Yes. A 10 inch mattress typically feels more substantial than a thin mattress, with more noticeable comfort layers and often better pressure relief. If you are upgrading from a 6 or 8 inch model, you may experience increased cushioning and support, especially...

Is this mattress okay for everyday use or better for occasional sleep?

This extra-firm mattress is designed for regular nightly use for sleepers who enjoy a very firm feel. If you plan to use it daily, review the materials, firmness description, and customer reviews to confirm that its extra-firm profile matches your comfort...

Does this memory foam mattress have cooling features?

This memory foam mattress incorporates materials and design elements such as gel-infused or open-cell memory foam and breathable cover fabrics intended to help manage heat. Check the product description for specific cooling technologies included in ...

Is this an authentic Serta mattress?

This mattress is part of the official Serta lineup and is sourced through authorized distribution channels. You can verify authenticity by checking the law tag, model name, and branding on the product and packaging, which should clearly show the Serta...

Will this king mattress fit my existing bed frame?

Most king bed frames are designed for a mattress around 76 x 80. Check your frame's inner dimensions and compare them with the mattress measurements on the product page to ensure a proper fit without gaps or overhang.

Does this king mattress sleep hot?

Temperature regulation depends on the materials and cover. Mattresses with breathable fabrics, open-cell foams, cooling gel, phase-change materials, or coil support cores tend to allow more airflow and feel cooler than dense, non-ventilated foams. ...

Is this king mattress compatible with an adjustable base?

Many foam and hybrid king mattresses are compatible with adjustable bases and are designed to bend and flex as the base moves. Check the product description for specific notes on adjustable base compatibility and follow the manufacturer's guidelines...

Is this mattress a true memory foam mattress or just regular foam?

This mattress is a true memory foam design, using viscoelastic foam in the comfort system that responds slowly to pressure and contours closely to your body. You can confirm this in the construction and materials section, which specifies memory foam...

How long does it take for a king mattress to fully expand after unboxing?

Most boxed king mattresses expand to near full size within a few hours, but they may continue to relax and reach their final feel over 24-72 hours. Room temperature, ventilation, and the specific materials can affect expansion time; follow the manufacturer...

Do I need a mattress protector for this foam mattress?

A mattress protector is strongly recommended for any foam mattress. It helps keep the surface clean, protects against spills and allergens, and can extend the life of the mattress by preventing moisture and debris from breaking down the foam layers ...

What are the exact dimensions of this 10 inch mattress?

This mattress is approximately 10 inches high and is available in standard widths and lengths such as Twin, Twin XL, Full, Queen, King, and sometimes California King. Refer to the size chart on the product page for the precise width, length, and height...

Is this 10 inch mattress supportive enough for a heavier sleeper?

This 10 inch mattress is built with a support core and comfort layers designed for regular adult use. Heavier sleepers should review the firmness rating, material densities, and weight guidelines on the product page to ensure it is recommended for their...

Is there a weight limit for this 10 inch mattress?

Many mattresses list recommended weight guidelines for optimal performance. Check the specifications and warranty on the product page to see if there are any stated weight limits. If you are near or above the recommended range, you may want to consider...

Will standard sheets fit on a 10 inch mattress?

Yes. Most standard fitted sheets are designed to fit a range of mattress depths and will accommodate a 10 inch mattress without issue. If you want a snugger fit, look for sheets with a pocket depth that matches low to medium profile mattresses and elastic...

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