What is a Box Spring?

July 26, 2021

A box spring is a bed base with a wooden frame and either springs or metal rods that provide support to a mattress. It is a type of foundation for mattresses. The box spring is usually the same size as the mattress that sits on it.

Ashley Sierra mattress on a gray box spring in a decorated bedroom. The mattress and box spring are labeled.

What is the Purpose of a Box Spring?

So, what does a box spring do? While the mattress provides support to the human body, the box spring ensures that the mattress itself is properly supported. It provides a stable surface for your mattress to rest on and absorbs shock, reducing wear on the mattress. This helps ensure your mattress maintains a long comfort life.

Box springs also raise the height of a mattress to make it easier to get in and out of bed. In a complete bed set, box springs are typically placed on top of a wooden or metal bed frame that's connected to the headboard and footboard. It's also common to see mattresses and box springs used together without a complete bed. Many sleepers who don't feel the need to have a decorative looking bed will place their box spring directly on the floor, or on casters that stand on the floor. Depending on what you need, there are different types of box springs.

Why Do You Need a Box Spring?

Although most modern mattresses don't need a box spring to be comfortable some mattress warranties still require a box spring. In some cases adding a box spring to your mattress enhances the comfort and support you get from your bed. The information below should answer the question, 'Do I Need a Boxspring?'

A box spring is necessary if:

  • Your mattress warranty requires one, helps to prevent your mattress from breaking down

  • You're using a bed frame (mattresses can't rest on those alone)

  • Your mattress is a traditional double-sided innerspring

  • You need or want the extra height, to make it easier to get into and out of bed

  • You want the added bounce and support a box spring offers

Sometimes a different type of foundation works better, depending on the type of mattress and your personal preferences. Learn more about that in our Foundation Guide.

Related: Which Mattresses & Box Springs Work with Platform Beds?

Height Options

Over the last several years, advancements in sleep technology have resulted in mattresses that are a lot taller than they used to be. For this reason, many manufacturers produce low profile box springs. as well as ultra-low profile box springs.

The difference in height is completely aesthetic. There's no difference in the amount of support they provide to the mattress. Whether you use a standard or low profile box spring, you can count on your mattress getting the support it needs. 


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Standard Profile

Standard box springs measure 9 inches in height.

Tempurpedic standard charcoal box spring


Low Profile Box Spring

Low profile box springs measure between 5 and 5.5 inches in height.

Tempurpedic low profile charcoal box spring


Ultra Low Profile Box Spring

Ultra-low box springs measure 2 inches in height.

Tempurpedic ultra low profile charcoal box spring


Related: What Type of Box Spring Should I Use?

Protect Your Mattress Warranty

Most manufacturers require that a mattress be supported by a box spring to file warranty claims. An exception to this is when a mattress lies on a platform bed or adjustable base. Since platform beds feature either wooden slats or a deck, the mattress doesn't need the extra support of a box spring.

The warranty also requires that the box spring be in good enough condition that it will not damage the mattress. Learn how to tell when you need a new box spring.

We Can Help!

If you're unsure if you should purchase a box spring with your mattress, or you have questions about a box spring you found on our site, give us a call. You can call 1-800-455-1052 to speak with a friendly mattress expert who'll be happy to assist you.


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