Does Your Bed-In-A-Box Mattress Need a Box Spring, Bunkie Board, or Foundation?

The bed-in-a-box market is booming, giving consumers dozens of manufacturers and materials to choose from, at extremely competitive prices.

While shopping for a bed-in-a-box and having it delivered to your door has plenty of perks, we wondered why box springs were a given with any new retail mattress purchase years ago, but they’re conspicuously absent from modern online options.

Which begs the question: If you’re about to purchase a new mattress online, should you buy a box spring or will any flat surface do the job?

In this guide, we’ll explore this question in detail as well as provide information on the foundation requirements of popular bed-in-a-box brands. We will also compare the various foundation options for a bed-in-a-box mattress.

What’s the Point of a Box Spring and What Benefits Does It Provide?

It’s been several centuries since humanity collectively upgraded from sleeping on wool, straw, or feather-stuffed sacks that were the first mattresses, and about as long since beds have been traditionally raised off the floor to help decrease vermin infestation, improve airflow, and make getting in and out of bed easier.

Given this, when did the box spring come along, and what purpose does it continue to serve in the modern world?

Although steel coil springs were first used during the 15th century, they weren’t formally implemented into bedding for shock absorption until German Heinrich Westphal invented the innerspring mattress in 1871.

Even then, it wasn’t until a couple of decades later, toward the end of the 19th century, that the box spring (i.e., “a frame containing rows of coiled springs that is used to provide support for a mattress”) was created. And still another 50 years before it came into vogue as a standard household item.

Regardless, by providing this support, the first box spring models were hybrid specialty sleep products designed to help make cotton-batting mattresses more comfortable by also by acting as a shock absorber.

Meaning that, no matter what happened above the mattress, the box spring took on the brunt of movement or weight. This also helped make sure the mattress always rested on an even surface, preventing the development of hollows or depressions where the occupants most often lay. 

First model box springAn example of an early box spring. Image via Sleep History

These coils have been redesigned over the years to provide stronger, more flexible support that can respond independently to movement and pressure for optimal weight transfer, thereby improving the sleeper’s comfort and prolonging the life of their mattress. But the reality is that support largely remains the purpose of box springs to this day.

Size-wise, standard modern box springs are 9 inches (23 cm) in height, whereas “low profile” box springs are between 5 and 5.5 inches (13 and 14 cm). According to The Oregonian’s Grant Butler, though, the difference between the two heights is purely aesthetic and makes no difference in the support provided for the mattress.

With these basics in mind, let’s dive right in and answer what’s perhaps the most pressing question on your mind.

Does Your Bed-In-A-Box Mattress Need a Box Spring?

The short answer: If you purchased your mattress within the last couple of years, probably not—at least from a comfort perspective. But be sure to check with the manufacturer and verify any of their specific requirements, or you could potentially void your warranty.

The detailed answer: According to online retailer US-Mattress, box springs were originally designed to provide support to two-sided mattresses, which were frequently flipped.

But, what about in today’s times? Do modern innerspring mattresses need a box spring? Even for other models, such as layered memory foam, does a box spring make a mattress softer? Does a box spring make a difference in overall comfort?

Because two-sided mattresses are rarely in use today, US-Mattress notes that most modern one-sided mattresses, whether made from memory foam or another material, are fine to use on any flat, level, hard surface. Why is this?

If you purchased a mattress within the last few years that contains inner-springs (heat-tempered coils that can maintain their shape for up to two million compressions), they generally contain all of the components within the single unit to provide the necessary support traditionally offered by a box spring.

In fact, it’s often the case that the number of coils used in box springs isn’t numerous enough to handle the combined weight of a modern innerspring mattress, plus sleepers.

Beyond innerspring mattresses, new materials such as memory foam, latex, and gel-infused materials no longer require a spring-based foundation, since they often provide sufficient support and shock absorption on their own.

As a result, most mattresses today use foundations that are simply sturdy, inflexible boxes made of wood or metal. They rarely include any actual springs, although they’re sometimes grouped together with ‘box springs.’

Given everything we’ve learned here, technically, all you need is a hard, flat surface to set most modern mattresses on. This could be an adjustable base, platform bed, box spring, or even a hardwood floor.

However, retailer US-Mattress emphasizes that your mattress’s warranty may require the use of a box spring or platform bed, so be sure to verify these details in advance. Otherwise, you might risk voiding coverage (we’ll come back around to this topic shortly).

Speaking of which, let’s take a look at what some of the most popular bed-in-a-box companies require.

Foundation Requirements of Popular Bed-In-A-Box Mattress Brands

After investigating dozens of the most popular bed-in-a-box companies, we’ve learned that, due to the difficulties of shipping a traditional box foundation, few require their use for warranty purposes.

However, that doesn’t mean that there aren’t restrictions you should be aware of. For example, platform beds are almost always okay, but old box springs generally aren’t.

If you’re concerned about protecting your mattress’s warranty to ensure that whatever you put it on complies with the fine print, here’s a quick reference guide for what popular online mattress retailers suggest:

Company Cushion Types Warranty Required Foundation Suggested Foundation
Casper OEKO-TEX Latex, Memory 10 Years A firm, raised foundation. No floor. Casper foundation and metal bed frame; bunkie board between old box spring; firm platform or slatted base with thick, unyielding slats.
Cocoon by Sealy Memory, Support foam 10 Years A flat, sturdy foundation, adjustable bed base, or bed frame. N/A
intelliBED Spring, soy foam, Latex, Intelli-gel 20 years Frames that have a support that runs down the center of the mattress, connects at both the head and foot of the frame, and properly supports the mattress for a flat, firm surface N/A
Leesa Memory, Avena 10 Years A solid (non-spring) foundation. Platform or slatted foundation (no more than 3” apart).
Lull Gel-infused memory, Polyurethane 10 Years N/A Platform, adjustable, or slatted foundations (no more than 3” apart), box springs, or floor.
Novosbed Ultra-dense memory 15 years Firm, non-springy foundations or adjustable bed bases that allow air to circulate beneath—cannot be placed on the floor. Per terms, must have “a center support and having at least 5-6 legs for queen, king and California king and 4 leg support for twin and full mattresses.” Slats must be a minimum of 2" in width, and have gaps between them of no more than 3". N/A
Purple Comfort, Support foam 10 years Firm, flat, solid-surface, non-spring foundation, whether non-moving type or adjustable type. Queen or larger must have 5 or more legs including a center support. N/A
Saatva Wrapped coils, Memory foam 15 years Metal frame with 5- or 6- legs on Queen or King size. Saatva adjustable base suggested.
Tuft and Needle High-density, pressure-relieving adaptive foam 10 years No specific requirements listed. Flat, adjustable, or slatted foundations (no more than 4" between slats), Tatami Mats, or box springs. If on the floor, T&N recommends lifting it every 2-3 weeks to briefly air out.
Yogabed Memory, YogaGel 10 years Foundation with a center support that has at least 5 to 6 support legs (Q, K, CA King) or 4 support legs (twin, twin XL, and full). All-In-One Frame Foundation
Zenhaven Talalay latex, Wool 20 years Foundation with a center support that has at least 5 to 6 support legs (Q, K, CA King) or 4 support legs (twin, twin XL, and full). Saatva adjustable base foundation suggested.

Whether the brand you’re considering requires one, or you simply prefer the aesthetics, let’s now discuss the different foundation choices available for direct-to-consumer mattresses.

Foundation Options for a Bed-In-A-Box Mattress

1. Your Existing Box Spring

If you already own a box spring, chances are you’ve considered just placing your new mattress on top and calling it a day. After all, doing so is the easiest way to save money. However, if your box spring is too dilapidated, resting a new mattress on top can cause discomfort and shorten the life of your new purchase.

How to tell if it’s too worn out?

The Sleep Sherpa recommends: “A good rule of thumb is that if the box spring is older than 10 years, it probably needs replacing. You can also tell just by pushing on it. If it is springy, then get rid of it.” If it squeaks, this could be another sign that it’s time to go.

If you’d like to triple check whether or not you need a new box spring, you can take a board, measuring tape, or even a string and stretch it from edge to edge, both horizontally and vertically, to create a level point of reference.

If you see a depression in your box spring of one inch or more, it’s no longer fit for use and should be replaced. Or, you can attempt to extend the life of your old foundation using what’s called a bunkie board.

2. Bunkie Board

Bunkie (or bunky) boards are cloth-covered pallets that provide a solid foundation in lieu of a box spring or base. These can be placed in between your new mattress and old box spring to create a sturdy, even foundation.

A Bunkie BoardA bunkie (or bunky) board can be placed over slatted foundations—or even old box springs—to boost support and extend a mattress’s usable life. Image via Apartment Therapy

Many manufacturers also recommend using bunkie boards underneath foam or latex mattresses that rest on slats to maximize comfort and service life.

Can you use a bunkie board on a metal bed frame? Your previous boxspring and mattress may have been elevated using a generic metal frame with a few thin beams, which obviously won’t work with just a mattress. The good news is that you’ll almost certainly be able to find a bunkie board that matches the dimensions of your metal frame, which can help deliver the support you need. Just be sure to carefully place the bunkie board on the frame or you could tear the fabric.

Bunkie board vs. box spring (standard and low-profile): Based on what we’ve briefly covered already, we can see that bunkie boards and box springs look and function much differently from one another, although the underlying goal of both is to provide adequate mattress support. 

Again, if you have an older mattress, it may require the use of a box spring, while the majority of modern bed-in-a-box models will work fine with a bunkie board. 

3. Box Foundation & Slatted Base

As we mentioned above, although modern boxed foundations usually don’t actually contain springs, they’re frequently mislabeled ‘box springs.’ But since these foundations and slatted bases feature similar construction, with horizontal supports secured down a center support, what’s the difference between the two?

In truth, not much. The only difference is that a standard boxed foundation may have a thin piece of cardboard covering the slats before being encased in fabric, whereas with ‘slatted’ models, these wood slats are open and visible.

Bunkie board vs. slats: Compared to a solid bunkie board, wooden slats have spaces in between that could cause the same sagging concerns as a metal frame by itself, so the ideal solution is to typically place a bunkie board over wooden slats for optimal support.

However, some bed-in-a-box mattress manufacturers note that slatted foundations are acceptable, as long as each slat is at least two inches wide, and there’s no more than a three-inch gap between each one.

4. Adjustable Foundation

If you enjoy the idea of being able to elevate the head or foot of your mattress (or even of a massage function with some high-end models), you can get an adjustable power base for your mattress. This type of base typically includes a motor, some of which can even be controlled via a smartphone application.

You can actually get these delivered by Amazon for pretty low prices, as well as any other mattress retailer, including third-party online retailers—some for just a few hundred dollars.

However, adjustable bases can’t be used with every type of mattress. Innerspring mattresses, for example, lack the flexibility necessary to elevate either the head or foot.

Also, know that the repetitive motion caused by adjustable foundations can weaken the structure of flexible foam and latex mattresses and may void your warranty. Again, be sure to double-check your mattress’s warranty before deciding on a foundation, adjustable or otherwise. 

5. Platform Beds

Platform beds provide a hard, flat surface via a solid piece of particleboard (similar to a bunkie board), or wooden slats, which support your mattress. Platform beds also offer other potential advantages like storage space underneath, along with a sleek modern look.

In the vast majority of instances, platform beds will provide all the required support your new mattress needs.

However, since wooden slat and platform foundation models can occupy the same niche, it’s important to reiterate that, in our experience, most online-only memory foam manufacturers recommend that slats are at least 2" in width, with gaps no more than 3" apart.

Can You Place Your Mattress Directly on the Floor?

Some online mattress retailers (listed below) suggest that your new mattress can be placed directly on the floor. This can actually give the mattress proper support, but there are a few concerns:

  • Reduced airflow: Since the mattress sits directly on the floor, it will not be able to expel air and breath as easily as it could on a box spring or platform bed. This could potentially lead to hotter sleep, and according to The Sleep Advisor’s Mark Reddick, even microbial growth—especially if you live in a humid environment. Speaking of which…

  • Less hygienic: Being in direct contact with the floor means your mattress can get dirtier, faster. This could be especially problematic if you have allergies or are otherwise sensitive to airborne irritants. 

  • More difficult to get into: if you’re older or otherwise experience mobility or flexibility concerns, having a mattress on the floor can make getting into and out of bed more difficult.

  • Void your warranty: Not to sound like a broken record, but some warranties dictate that the mattress must remain on a box spring or platform bed. Before doing anything, double check the warranty terms.

However, the reality is that living in tiny apartments or sticking to restricted budgets sometimes mean that a traditionally raised bed isn’t an option. If your mattress absolutely must sit on the floor, follow these steps for your best shot at preventing mold and mildew:

  1. Check the mattress size and find a suitable place to lay it. Clean the area properly beforehand and get rid of any dust and dirt. Use a vacuum cleaner, or wipe the floor with water if it is not carpeted. Consider applying a disinfectant such as bleach to cleanse the laminate or wood of any bacteria. Let the area dry completely before you lay the mattress down.

  2. If the floor does not have a carpet, use materials like a sheet of polyethylene, foam, or even a few yoga mats, which will help create a buffer to keep cold drafts from permeating your mattress.

  3. If your mattress is floor-based for long periods of time, lift it up and set it against a wall with no bedding to allow the underside to air out regularly—at least once a week. Fans, air conditioning, air purifiers, and dehumidifiers, if available, can also help maintain circulation and prevent mold accumulation. At this same time, clean the area to remove dust, dirt and any other organisms that may be invisibly lurking there.

  4. The Sleep Judge’s Frank Apodaca also recommends using a breathable mattress cover, changing the sheets often (see step number three above), avoiding laying on your mattress fresh out of the shower or pool, or with otherwise wet hair; and keeping all damp clothes and towels away from the mattress at all times. 

What’s the Bottom Line Regarding Box Springs & Mattresses?

In the end, despite so many new materials and brands to choose from, including new ways to buy mattresses completely online, one thing appears certain: traditional box spring bases are largely a thing of the past.

From this vantage point, whether you decide to place your new mattress on a box, platform, slat-based, or adjustable foundation is mostly a matter of preference, as well as any stipulations outlined in the manufacturer’s warranty.

Given this, if you’re still in the stage of picking between brands or deciding between memory foam, latex, gel column, or traditional innerspring, our Bed-In-A-Box Mattress Buying Guide could be the ticket to starting out on the right foot and coming to a more informed decision.

Autumn Yates

Autumn draws from a reporting background and years of experience working remotely, while living abroad, to focus on topics in travel, beauty, and online safety.

Sign Up for HighYa Newsletter

Sign up for HighYa newsletter and get our best content delivered in your inbox as well as 3 free eBooks to help you save money and shop smarter. Enter your email below to get started!