Most modern mattresses, especially foam and hybrid, need a solid or slatted platform, not a traditional box spring. Box springs suit older innerspring beds. Using the wrong base can void your warranty, so check the maker’s requirements, usually slats no more than 3 inches apart.
The base under your mattress affects support, height and even your warranty. Here is how to choose between a platform and a box spring. To pick the mattress itself, see our mattress buying guide.
What each one does
A box spring is a coil or wood frame that adds height and absorbs shock, designed for traditional innerspring mattresses. A platform bed has a solid or slatted surface that supports the mattress directly, no box spring needed.
What modern mattresses need
Memory foam and hybrid beds need firm, even support. A platform with solid surface or slats spaced no more than about 3 inches apart is ideal. Putting a foam mattress on an old box spring can cause sagging and may void the warranty.
Height and storage
Box springs raise the bed higher, which some people prefer for getting in and out. Platforms sit lower and modern designs often add under-bed storage.
Check the warranty
Many mattress warranties specify the required base and slat spacing. Always confirm before buying a frame. Browse options in our bed frame reviews.
Frequently asked questions
Do I need a box spring with a foam mattress?
No. Foam and hybrid mattresses need firm, even support from a platform or closely spaced slats. A box spring can cause sagging and may void the warranty.
What is the difference between a platform bed and a box spring?
A box spring is a separate sprung base for innerspring mattresses that adds height. A platform bed supports the mattress directly with a solid or slatted surface.
How far apart should slats be?
No more than about 3 inches for most modern mattresses. Wider gaps reduce support and can void the warranty.
