A good box spring (a.k.a. a mattress foundation) should do a few things: provide support for your mattress, raise it to a more comfortable height, and even help keep it free of dust. According to Logan Foley, a product expert at sleep-advice website SleepFoundation.org, a box spring can also “absorb impact, which can then help preserve and lengthen the life of your mattress by reducing wear and tear.” Traditionally, box springs had inner coils, but Mitch Costner, a buyer and sleep expert for Mattress Firm, says that old-school design has been phased out to accommodate modern mattresses. “With the majority of mattresses shifting to memory foam, hybrid, or springs with more memory foam in them, the bases need to be less flexible and more rigid to support this type of mattress construction,” Costner explains, pointing out that box springs can also “limit dust and allergens on the floor from seeping into your bed” from underneath.
Before you decide on a box spring, consider whether you actually need one. According to Foley, a box spring is the most useful in three specific scenarios: “If you are using a metal bed frame that is designed to cradle box springs; if you have an older innerspring mattress; or if you are trying to elevate your bed to make it easier to get in and out of.” John Merwin, CEO of 3Z Brands, the parent company of several mattress-in-a-box brands, adds that since most modern mattresses are intended to lay directly on the slats of your bed — box springs are almost always optional. If you have a platform bed, for example, Merwin says you can skip the box spring unless you’d simply like to add more height.
To help you find the best box spring for your particular sleep setup, we talked to Foley, Merwin and Costner about what makes a quality box spring and rounded up the best ones available to buy online.
What we’re looking for
Materials and level of flex
Box springs can be made of metal or wood, include coils or slats, or have a mix of a few materials. You’ll notice that the box springs below don’t actually contain coils, unlike the box springs your parents may have had, as the coil-filled options aren’t compatible with more modern mattresses. Even though the term “box spring” is still common, modern box springs are more of a mattress foundation, acting as a firm platform for your mattress to rest on.
Zero-deflection box springs have sturdy steel or wood slats that don’t flex, creating a firm and flat supportive surface. According to Foley, the firmness and stability provided by zero-deflection box springs are essential if you have a heavier memory foam or latex mattress, as those types of mattresses require more support.
Semi-flex box springs usually consist of a wood frame topped with a metal grid over the slats. Semi-flex box springs are ideal for adding the bounce of coils and the firm platform of a mattress foundation. These types of box spring still work well with weighty memory foam and latex mattresses, because they are supportive while still being lightly flexible. They tend to be more expensive than zero-deflection box springs.
The ideal box-spring height depends on your preferences around the overall height of your bed, the height of your mattress, and the height of your bed frame. The typical rule of thumb is that you should be able to sit at the edge of your bed with your legs at a 90-degree angle. Many box springs come in a variety of height options. If you like your bed closer to the ground, you’ll want a low-profile box spring around four or five inches tall. But if you like feeling lifted, or have limited mobility and want to make it easier to get in and out of bed, you’ll want a box spring that’s seven or nine inches tall. We’ve listed the height options for each of our picks.
The weight capacity of a box spring can vary depending on the material that it’s made of as well as the size and number of slat it has. If you have a heavier memory foam or latex mattress, you’ll want to include that in your overall total along with the weight of anyone who will be sleeping in the bed. We’ve listed the weight capacity of each box spring below.
Best overall box spring
Materials and flex level: Steel, zero-deflection | Height: 5-inch, 7-inch, or 9-inch | Weight capacity: 700 pounds for full size and larger; 350 pounds for twin and twin XL
Zinus, the maker of some of our favorite affordable but high-quality mattresses, is also behind some of our favorite box springs, including this best overall nine-inch model. It’s made of durable, zero-deflection steel, and the full, queen, and king sizes can support up to 700 pounds. The steel frame is covered by a soft-knit polyester cover that pulls down over the frame like a fitted sheet, and assembly is simple — many of the frame components snap together with locking buttons, and any tools you’ll need are included. This box spring is also available in a low-profile five-inch height and a mid-profile seven-inch height.
Best less expensive overall box spring
Material and flex level: Steel, zero-deflection | Height: 5-inch, 7-inch, or 9-inch | Weight capacity: 350 pounds for all sizes
As long as a 350-pound weight limit will suffice, this Amazon Basics box spring is extremely easy to assemble, with no tools required: It more or less snaps together in six easy steps, and the whole thing takes about 20 minutes, according to reviewers. You can choose between a five-inch, seven-inch, or nine-inch height, and one detail that sets it apart from other box springs on this list is that it has a two-piece cover that encloses the entire frame, even the bottom, and zips off for easy spot cleaning.
Best metal box spring with 3” slat spacing
Material and flex level: Steel, zero-deflection | Height: 4-inch, 7.5-inch, or 9-inch | Weight capacity: 700 pounds for full size and larger; 350 pounds for twin and twin XL
This Zinus model has more steel slats running the length of the bed than our top pick Zinus box spring above, with about three inches between each to provide better weight distribution. If more slats sound like more work to you to put together, think again: This one uses Zinus’s Quick Lock assembly system, which means the slats snap into place — no screws needed. The box spring can support up to 700 pounds and you can choose from three heights — four, 7.5, and nine inches.
Best box spring with wood slats
Material and flex level: Steel and wood slats, zero-deflection | Height: 4-inch, 7.5-inch, or 9-inch | Weight capacity: 700 pounds for full size and larger; 350 pounds for twin and twin XL
For those who prefer wood slats, this box spring combines the strength of steel in the base with the slight yet sturdy give of wood in the slats, which some sleepers say offers a more comfortable night’s rest. The slats of this box spring are spaced about three inches apart for maximum sturdiness and support, and they’re strung together so you don’t have to worry about spacing them correctly — just unroll the bundle and lay them on the box spring’s frame. As with all Zinus box springs, this one is praised for how easy it is to assemble. It comes in four-inch, 7.5-inch, and nine-inch heights.
Best upholstered box spring
Material and flex level: Steel and wood, zero-deflection | Height: 4-inch, 7.5-inch, or 9-inch | Weight capacity: 700 pounds for full size and larger; 350 pounds for twin and twin XL
This upholstered box spring from Zinus offers a crisp, clean design. It’s made of strong steel for the base and 2.8-inch wood for the slats, but that’s all hidden beneath a gray woven fabric cover for a polished look. As some reviewers note, that means even when their box spring peeks out from under the covers or there’s no bed skirt, it looks okay. And of course, it’s easy to assemble, with a base that comes together in steps. The wood slats are encased in a fabric covering that makes them even easier to roll out onto the frame.
[Editor’s note: This box spring is not currently available in a twin size.]
Best solid-wood box spring
Material and flex level: Wood, zero-deflection | Height: 4-inch or 8-inch | Weight capacity: 500 pounds for full size and larger; 250 pounds for twin and twin XL
Instead of having a steel frame, this Zinus box spring is made of solid wood, both the base and the slats, with the slats made of thicker wood than most to ensure a solid base. It comes in two heights, four inches or eight inches. This box spring comes together in three quick steps, with all the tools you need — a small Allen wrench and a ratchet — included in the box. The inside of the frame is lined with Velcro, and the slats are rolled into a bundle that attaches to the Velcro as you unroll it, ensuring proper placement. It also has a fully enclosed cover that zips closed.
Best semi-flex box spring
Material and flex level: Steel and wood, Semi-flex | Height: 5.5-inch, 8.5-inch | Weight capacity: 750 pounds for all sizes
Semi-flex box springs are sturdy options that work well with all mattress types, including heavier memory foam and latex mattresses, but their construction offers a bit more bounce and give than zero-deflection box springs. This Kingsdown box spring is made of high-quality steel connected to a wooden frame, and can hold up to 750 pounds no matter which size you buy. It’s available in two heights: a low 5.5-inch height and a taller 8.5-inch option. It is also covered in breathable cotton that promotes airflow, which Costner says “can impact your quality of sleep by enhancing airflow through your mattress, making for more quality sleep.”
Best foldable box spring
Material and flex level: Steel, zero-deflection | Height: 8-inch | Weight capacity: Not listed
At first glance, the Ascension Bi-Fold Foundation looks like your typical fabric-covered box spring. While it checks all of the important boxes — adding height (in this case eight inches), absorbing impact, and providing mattress support — the all-steel foundation can be folded in half for effortless transportation. The easy-to-assemble construction is tool-free, and the fabric cover can be removed to make folding easier.
[Editors’ note: This box spring is currently available in twin and twin XL sizes only.]
Best motion-isolating box spring
Material and flex level: Steel and wood, zero-deflection | Height: 5-inch or 9-inch | Weight limit: Not listed
If you sleep with a partner, you may be well acquainted with feeling them toss, turn, and shuffle around while they sleep. Though most newer mattresses help limit that motion, the Serta Perfect Sleeper box spring, a favorite of Costner’s, can further assist. Built with a high carbon steel grid and a kiln-dried hardwood frame, it helps to absorb impact and minimize movement. This box spring is available in a low five-inch profile and a higher nine-inch profile, and no assembly is required. It is also covered in gray fabric for a more finished look.
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