Beautyrest® Flat Foundation


A box spring alternative that provides the perfect support for your Beautyrest® mattress.

76" long x 40" wide x 9" high
You'll be notified when this product is back in stock.

The Beautyrest experience

Find the perfect match

Let our experts help you find the right mattress for your sleep style.

Call 877-298-4955 Find a store

  • Overview
  • Details
  • Shipping & returns
If you are looking to add a little height to your bed or just simply extend the life of your Beautyrest® mattress, the Beautyrest® Flat Mattress Foundation is the perfect solution. Designed to provide long-lasting comfort, the Beautyrest® flat bed foundation includes a spruce framework and welded steel elements for greater support and durability. 
  • Available in all standard sizes
  • Center support extends to the floor for queen or king sizes 
  • Meets or exceeds State and Federal Fire Retardancy Standards when used either by itself or with an approved Beautyrest® mattress

Materials & Construction
Foundation height: 9”

Twin: 74"L x 37.5"W x 9"H
Twin XL: 79"L x 37.5"W x 9"H
Full: 74"L x 52.5"W x 9"H
Queen: 79"L x 59.5"W x 9"H
King: 79"L x 75"W x 9"H
California King: 83"L x 71"W x 9"H

Beautyrest® foundations are designed to be supported by platform frames or traditional bases.

All of the Beautyrest mattresses and bases sold here are conveniently delivered using our complimentary White Glove Delivery experience. Typically, within 1 week of placing your order, you’ll be contacted by our shipping partner to select a delivery day that works best for your schedule. The day of your delivery, you’ll get a call confirming your delivery window. Upon delivery, they will set up your new mattress and remove your old mattress and any packaging for that mattress.  Most items ship in 2-4 weeks. We do not ship to Alaska or Hawaii at this time.

Your base purchase includes a 100-Night In-Home Trial. If, at any point during your trial, you are unhappy with your Beautyrest® mattress, simply reach out to us and we will help you initiate a return and receive a full refund of your purchase.


What is the difference between the C class K class and L class?

The Beautyrest Black mattresses come in a variety of firmnesses and styles, from traditional tight-top mattresses to pillow tops. They also all feature our T3 Pocketed Coil support system for the most consistent support and durability, our all-night cooling technology, BlackICE with plant-based cooling, to provide more cooling power to keep you comfortable as you fall asleep and all night long, and our Technoluxe Memory Foams for the best pressure relief out there, the differences between the 3 classes are as follows. 


The L-Class models are our basic models. They have all of the features mentioned above, but nothing extra. This model will offer all-night cooling and immediate pressure relief, while still providing consistent support. 


The C-Class models were designed to implement even more comfort and immediate pressure relief, on top of what is offered in the L-Class line. The C-Class models will include comfort layers made with Alpaca, Cashmere, and Silk Fibers to incorporate more comfort in your mattress while continuing to ensure airflow and breathability. The C-Class line will also add a layer of Self-Response Latex to incorporate a unique support and pressure relief specific for your hips and shoulders.


The K-Class models feature all the benefits of the C-Class, but the K-Class will provide up to 30% more pressure point relief than the C-Class because of the utilization of our 2K Nano-Coils. These unique coils were designed to provide enhanced conformability and pressure relief, with individualized back support for each individual shape. The K-Class line has the most upgrades and sleep benefits of all 3 lines and will provide the most luxurious sleep experience by incorporating our Dynamic Response Memory Foam for more conforming support and maximized airflow.

What is the difference between a Hybrid and a Traditional Quilted Mattress? 

The Hybrid products are a cross between an all-memory foam mattress and innerspring mattresses. As far as the Hybrid goes, the top layer on which you lay is memory foam, all the way down to the layer of foam above the springs (the layer above the springs is usually the only non-memory foam layer and will be ½” polyurethane). When you lay on a Hybrid mattress, it usually feels more comparable to a traditional foam mattress, with a sinking-in feeling, but combines the bounciness of an innerspring mattress 


In the traditional lines, the foam layers are a combination of polyurethane foam and memory foam layers. The top layers will be polyurethane foam followed by memory foam layers deeper down in the mattress. Memory foam is a slow-recovery material, whereas, polyurethane foam is a quick-response foam. This will provide a very different feel than a Hybrid product. 


Additionally, Hybrid mattresses tend to have a flatter top, while traditional mattresses will have the more common tufted top.

Where can I try out your mattresses?

Beautyrest mattresses are available for purchase at retailers throughout the United States. Retailers can pick and choose which products they will have on display for consumers to try out. Retailers often change their inventory frequently.  

If you are looking to test out a specific mattress, we recommend calling your local retailer to see if they have it on display to test out.

What is the height of the Flat Mattress Foundation?

The Beautyrest Flat Foundation is 9" tall.

The Beautyrest Experience


Need help deciding? We're standing by at 877-298-4955.

Free Shipping & Returns

Shop worry-free with no hidden costs or fees.

Free Mattress Removal

To make room for your new purchase.

100-Night Sleep Trial

100 nights to decide if it's right for you.

Hassle-Free Warranty

We make it simple so you can rest easy.

Man and woman laying face up on a beautyrest black mattress smiling

Try our mattresses in over 3,000 stores

Experience luxurious comfort in person.

Join the Mailing List

Be the first to find out about new arrivals, special offers, and more.

There was an error. Please try again.

By signing up, I agree to receive Beautyrest’s email newsletter.

Privacy Notice

1 item added to cart

Beautyrest® Flat Foundation



Subtotal (1 item) $--.--

Shipping, Taxes, Recycling Fees $--.--

Calculated in checkout

Secure Checkout