Guides
How to Store a Mattress
Quick answer
Store a mattress flat, not on its side, for anything beyond a short move. Foam and coils deform under their own weight over time when a mattress leans, so a flat, dry, off-the-ground storage position is what actually protects it. Never re-compress a mattress that shipped compressed; that process is not designed to be repeated.
Storing a mattress seems simple until it comes out of storage months later noticeably lumpy, curved, or smelling of damp, at which point the mistake usually happened when it went in, not while it sat there. The rules here are short and mostly about avoiding one of a small number of predictable mistakes, the kind that are easy to make once, during a move or a renovation, and expensive to discover later.
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What actually damages a stored mattress?
Two things account for nearly every ruined stored mattress: gravity acting on it in the wrong orientation, and moisture. Standing a mattress on its side for an extended period lets its own weight pull down through the structure unevenly, which permanently deforms foam layers and can bend coils out of alignment over weeks or months, producing a lasting curve or soft spot that was never there when it went into storage. Moisture, from a damp garage, a basement, or direct contact with a concrete floor, gets absorbed into foam and fabric and can lead to mildew, which is both a comfort and a hygiene problem once it sets in. Neither of these is really about how long the mattress sits in storage; a mattress stored correctly for a year fares better than one stored incorrectly for a month.
Storing a mattress briefly during a move
A short-term move is a different situation from extended storage, and the rules relax somewhat as a result. Standing a mattress on its side for the hours it takes to load, transport, and unload it is generally not long enough to cause the kind of gravity-driven deformation that extended storage on its side produces. The distinction is duration: hours are fine, weeks are not. If a move stretches into an unplanned delay, lay the mattress flat as soon as there is a surface to put it on rather than leaving it leaned against a wall for the interim.
How to store a mattress correctly
- Store it flat. Lay the mattress flat, ideally on a rigid, elevated surface such as a bed frame, pallets, or a flat table, rather than directly on the floor. Flat storage distributes the mattress's own weight the way it is designed to be loaded.
- Keep it off concrete. Concrete floors hold moisture and transfer cold, both of which encourage condensation against the mattress's underside. A few inches of clearance, on pallets or a low platform, breaks that contact.
- Control humidity in the storage space. A dry storage unit, garage, or basement matters more than the mattress cover does. If humidity in the space is a known issue, address that before assuming a plastic cover alone will protect the mattress.
- Cover it, but let it breathe if possible. A breathable cover protects against dust and surface moisture without trapping condensation the way a fully sealed plastic wrap can in a space with temperature swings.
- Never re-compress it for storage. A mattress that arrived compressed and rolled was compressed once, under factory conditions, as part of its manufacturing and shipping process. That process is not designed to be repeated at home, and attempting to re-compress and re-roll a mattress for storage risks damaging its internal structure.
Flat versus on its side
| Orientation | What happens over time |
|---|---|
| Flat, elevated off the floor | Weight distributed as designed; the safe option for any extended storage |
| On its side, briefly during a move | Generally fine for hours, not a structural risk in the short term |
| On its side, for weeks or months | Foam and coils deform under the mattress’s own weight, producing a lasting curve or soft spot |
Convention, not a standard
This is widely repeated guidance rather than a measured standard. Treat it as a starting point.
"Briefly" and "extended" are not precisely defined figures anywhere in the category; the safer default for anything beyond moving it between rooms is to lay it flat as soon as possible.
A mattress that came out of storage damaged
Protect what goes back on the bed
SafeRest Waterproof Queen Size Mattress Protector
$39.99A waterproof protector for the mattress once it comes back out of storage, guarding against spills and moisture going forward.
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PlushDeluxe Bamboo Waterproof Mattress Protector
$37.99A breathable waterproof protector, a reasonable choice when humidity is a concern in the room the mattress returns to.
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Meliusly Original Bunkie Board Queen Size - Under Bed Support
$99.99A flat, rigid, elevated surface to store a mattress on, keeping it off the floor.
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Utopia Bedding Adjustable Bed Risers 3 & 5 Inch
$19.99Raises whatever flat surface the mattress rests on during storage, adding clearance above a concrete floor.
Check price on AmazonFrequently asked questions
Can I store a mattress on its side?
Briefly, such as during a move, it is generally fine. For weeks or months, no: a mattress leaning on its side lets its own weight pull down unevenly through the foam or coils, which can permanently deform the structure into a lasting curve or soft spot. Store it flat, ideally elevated, for anything beyond a short-term move.
How should I store a mattress long term?
Flat, on a rigid elevated surface such as pallets, a low platform, or a bed frame, kept off a concrete floor and in a dry space with controlled humidity. A breathable cover protects against dust and surface moisture without trapping condensation the way a fully sealed plastic wrap can where temperatures swing.
Can I re-compress a mattress to store it?
No. Factory compression happens once, under manufacturing conditions, as part of shipping a new mattress, using equipment built specifically for that job. That process is not designed to be repeated at home, and attempting to re-compress and roll a used mattress for storage risks damaging its internal foam or coil structure permanently rather than protecting it for future use.
Why does a stored mattress sometimes smell musty?
Usually moisture, either from a damp storage space, direct contact with a concrete floor, or condensation trapped under a fully sealed plastic cover in a space with temperature swings. Elevating the mattress off the floor, controlling humidity in the room, and using a breathable rather than fully sealed cover all reduce the chance of a musty smell developing.
Does storing a mattress in a garage ruin it?
Not necessarily, but garages commonly have the two conditions that do the damage: temperature swings that encourage condensation, and direct or near-direct contact with a concrete floor. Elevate the mattress on pallets or a flat platform and use a breathable cover, and a garage can work fine for extended storage.
How long can a mattress safely sit in storage?
There is no fixed time limit; what matters is orientation and moisture, not duration. A mattress stored flat, dry, and off the floor for a year fares better than one leaned on its side in a damp space for a month. Correct storage conditions protect a mattress indefinitely; incorrect conditions can cause damage quickly.
How to read the numbers on this page. Standard mattress and bedding dimensions are industry-wide and the same across manufacturers. Guidance like replacement intervals, firmness by body weight and walking clearance is convention rather than a measured standard, and every table here says which it is. Where a manufacturer does not publish a figure we leave it out instead of estimating. This is not medical advice: a mattress is not a treatment for a medical condition, and persistent pain is a reason to see a clinician.