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a 9 inch flat foundationa 9 inch flat foundation
9 Inch Foundation
a 9 inch flat foundationa 9 inch flat foundation
9 Inch Foundation

    Flat Foundation

    Engineered to support your Stearns and Foster® mattress with a perfectly solid, flat surface.

    Profile
    $315.00
    Free Delivery — Arrives in 2-3 Weeks

    • Designed in the USA
      Crafted with care and to last

    • Designed in the USA
      Crafted with care and to last

    • Free Shipping
      Arrives via UPS Ground Delivery



    Fashion
    + Function

    The perfect mattress isn't complete without the perfect foundation. Our flat foundations are designed to take the place of a traditional box spring and can be placed directly on your existing bed frame.

    SF Lux Estate mattress on a foundation
    SF Lux Estate mattress on a foundation

    Fashion


    + Function

    The perfect mattress isn't complete without the perfect foundation. Our flat foundations are designed to take the place of a traditional box spring and can be placed directly on your existing bed frame.

    SF Mattress on a foundation

    CRAFTED TO

    Complement


    Constructed with the finest textiles, our Stearns & Foster® foundation is designed to enhance the look and feel of your mattress.


    Why You'll Love It

    SF Lux Hybrid mattress on a foundation



    Perfect Match

    Our solid surface foundation is crafted to provide years of stationary support. Designed and upholstered to complement our mattresses and your bedroom décor.

    Why You'll Love It

    SF Lux Hybrid Mattress on a foundation Mobile


    Perfect Match

    Our solid surface foundation is crafted to provide years of stationary support. Designed and upholstered to complement our mattresses and your bedroom décor.

    An image showing the difference in height between the 5 and 9 inch foundations


    Custom Comfort

    Our foundations are available in a 9” height that matches a traditional box spring and a lower 5” profile for a more modern look that will easily fit through more narrow stairways.



    Custom Comfort

    Our foundations are available in a 9” height that matches a traditional box spring and a lower 5” profile for a more modern look that will easily fit through more narrow stairways.

    SF_flatbase2.original
    SF mattress on a foundation

    Crafted


    For you

    Constructed with the finest textiles that enhance the look and feel of your mattress, our Stearns & Foster® Foundation is designed to complement your style.

    Looking to Upgrade Your Bed?

    Get a $200 instant gift when you purchase an Ease Base with your mattress. The Ease Base adds unlimited adjustable positions to help you sleep soundly at night and enhance your sleep sanctuary.

    $200 Instant Gift with an Ease Base

    Benefits:

    • Unlimited Head and Foot Positions
    • Wireless Remote Control
    • Zero Gravity Preset Position
    • Free Delivery and In-Home Set-Up

    Shop Now

    Looking to Upgrade Your Bed?

    Get a $200 instant gift when you purchase an Ease Base with your mattress. The Ease Base adds unlimited adjustable positions to help you sleep soundly at night and enhance your sleep sanctuary.

    $200 Instant Gift with an Ease Base

    Benefits:

    • Unlimited Head and Foot Positions
    • Wireless Remote Control
    • Zero Gravity Preset Position
    • Free Delivery and In-Home Set-Up

    Shop Now

    Product Specifications

    Size Availability:

    Twin: 74L" x 38W"

    Twin Long: 79L" x 38W"

    Full: 74L" x 53W"

    Queen: 79L" x 60W"

    King: 79L" x 38W" (each piece/ 2-piece foundation)

    CA King: 84L" x 36W" (each piece/ 2-piece foundation)

    Split Queen: 79L" x 30W" (each piece/ 2-piece foundation)

    Split King: 79L" x 38W" (each piece/ 2-piece foundation)

    Split CA King: 83L" x 36W" (each piece/ 2-piece foundation)

    Product Weight:

    High Profile 9"

    Twin: 31 lbs
    Twin Long: 35 lbs
    Full: 42 lbs
    Queen: 48 lbs
    King: 70 lbs (35 lbs each piece)
    CA King: 70 lbs (35 lbs each piece)
    Split Queen: 60 lbs (30 lbs each piece)
    Split King: 70 lbs (35 lbs each piece)
    Split CA King: 70 lbs (35 lbs each piece)

    Low Profile 5"

    Twin: 25 lbs
    Twin Long: 29 lbs
    Full: 38 lbs
    Queen: 46 lbs
    King: 58 lbs (29 lbs each piece)
    CA King: 58 lbs (29 lbs each piece)
    Split Queen: 58 lbs (29 lbs each piece)
    Split King: 58 lbs (29 lbs each piece)
    Split CA King: 56 lbs (28 lbs each piece)

    Warranty & Returns:

    Warranty: Your Stearns & Foster foundation is covered under a 10 year limited warranty

    Return Policy: This product cannot be returned and the 90-Night Trial does not apply.

    Care Instructions:

    For more information on how to properly clean and care for this product, please visit our Product Care page.

    Rated 4.768421052631579 out of 5 stars

    Read Our Reviews

    Rated 4.768421052631579 out of 5 stars
    95+ REVIEWS
    AVERAGE OF 4.8 STARS
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    Rating
    (85)
    (5)
    (1)
    (1)
    (3)
    Rated 5 out of 5 stars
    5
    Flat Foundation
    Apr 1, 2025
    Source:
    Stearns & Foster
    Sweepstakes

    The quality is excellent, very comfortable.

    Apr 1, 2025
    Lece , Blacklick Ohio
    Excellent sleep improvement. Great for my joints .
    Rated 5 out of 5 stars
    5
    Flat Foundation
    Mar 28, 2025
    Source:
    Stearns & Foster
    Sweepstakes

    Perfect height

    Mar 28, 2025
    Happier back , Austin TX
    We bought this with the new mattress and it made the bed just the right height. It also insures that the mattress is properly supported and that is important for your mattress warranty.
    Rated 5 out of 5 stars
    5
    Flat Foundation
    Mar 26, 2025
    Source:
    Stearns & Foster
    Sweepstakes

    Love My Stearns and Foster Bed

    Mar 26, 2025
    Resting Too The Fullest , Bryan, Texas
    Speaking with a Stearns and Foster Representative over phone was a True Pleasure, She Was Extremely Knowledgeable and Helpful! Placed My Order and Everything Went Just As She Said! Now I’m Enjoying My Bed To The Very Fullest Getting A Good Night Sleep Waking Feeling Totally Rested!
    Rated 5 out of 5 stars
    5
    Flat Foundation
    Mar 25, 2025
    Source:
    Stearns & Foster
    Sweepstakes

    Best night sleep ever.

    Mar 25, 2025
    Well rested, Kansas City, MO
    My husband and I have purchased Stearns and Foster mattresses and box springs since the early 1980s. Our 1st mattress and box springs lasted 20 years. When we purchased our 2nd, it was during covid and we blindly bought the Reserve Hepburn Plush mattress and box springs. I wasn't as thrilled with this purchase. The plush really wasn't firm enough, and the box springs fabric on the bottom kept shedding. I finally put a fitted sheet on it to keep it from shedding. Our 3rd purchase was just recently, and we love the mattress and 9 inch box springs, but we do have a 4 poster Harden bed that we were concerned that the height would hinder our ability to get into bed easily. So, we purchased another foundation-- the 5 inch foundation is awesome, and we currently have it with the Hepburn mattress. Someday, we might use it on our bed when we are unable to crawl into the higher one. The company that delivered the foundation took the old one that was shedding, so we didn't have to worry about what to do with it. I just love my Stearns and Foster mattress and foundation. I sleep better at night, and it's just perfect.
    Rated 5 out of 5 stars
    5
    Flat Foundation
    Mar 21, 2025
    Source:
    Stearns & Foster
    Sweepstakes

    Comfortable and supportive.

    Mar 21, 2025
    Happy Sleeper, New York, NY
    We've enjoyed our new Stearns and Foster mattress. The pillow top provides great comfort, while the core of the mattress provides gentle support and makes for a comfortable night's sleep.
    Rated 5 out of 5 stars
    5
    Flat Foundation
    Mar 18, 2025
    Source:
    Stearns & Foster
    Sweepstakes

    Quality product

    Mar 18, 2025
    Box spring happy, Forest, VA
    Received the product (short box spring) in states timeframe, am pleased with the quality/appearance, and appreciated being regularly informed throughout the delivery process.
    Load More Reviews


    BUILD THE BED OF YOUR DREAMS

    SF Reserve mattress on a flat foundation in a styled room

    Discover the handmade details and finest materials that make our mattresses truly exceptional.

    Shop Mattresses

    Lux Estate Mattress in a styled room raised on a base

    Upgrade to custom comfort with our Ease® Power Base—for a seamless sleep experience.

    Shop Power Bases

    or call (844) 483-4172

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