New mattress smell: why it happens, how long it lasts and how to air it out

Hi, we’re John and Mimi. “Is that smell normal?” is one of the first texts we get after a mattress arrives. A light “new” smell when you open a foam mattress is common, and it usually fades on its own. Here’s why it happens, how long it typically takes, the simple steps that speed it up, and what our listings say about the foam inside each mattress.

The short answer

• A light “new” smell is normal for a foam or hybrid mattress that ships rolled in plastic. Many people call it off-gassing.
• It usually fades within a day or two, sometimes a few days in a small room with little fresh air. That’s a rule of thumb, not a promise; every room is different.
• Air the room out: open the plastic in the bedroom, get the wrap and box out of the room right away, open a window and run a fan.
• You don’t have to wait to sleep on it. Our listings say you can sleep on it right away while it finishes expanding (up to 72 hours).
• Keep it dry. Skip soaking sprays and steam; the care instructions say not to steam it or let moisture saturate the mattress.
• Still strong after a week or so? Text John at 818-924-3744 and he’ll help.

Why does a new mattress smell?

Foam and fabric that were just made have a scent of their own. A mattress in a box is compressed, rolled and sealed in plastic soon after it’s made, so that scent stays trapped until you cut the wrap open. When the foam expands and air reaches it, you notice it all at once. That’s the smell people call off-gassing.

It’s usually strongest in the first few hours, and the more fresh air moves through the room, the faster it fades. A small, closed room keeps it around longer. All-foam and hybrid mattresses can both have it, since hybrids have foam comfort layers over the coils. Our memory foam vs hybrid guide explains how the two are built.

If you’re very sensitive to smells, or have asthma or other breathing concerns, ask your doctor what’s right for you. This guide is general shopping and setup advice, not medical advice.

How long does it last?

These are typical times, not guarantees. Expansion timing comes from our product listings; more on what each day looks like in how long a mattress in a box takes to expand and how to break in a new mattress.

How to get rid of new mattress smell faster

1. Unbox it in the bedroom. Put the rolled mattress on the bed frame or base first, then open it there. The care instructions say not to fold or bend it for long periods, so you won’t want to carry it around once it’s open.
2. Cut the plastic with scissors, not a razor blade, as every listing says, so you don’t nick the cover.
3. Get the plastic and box out of the room right away. Leftover wrap can hold some of the smell.
4. Open a window and run a fan. Cross-ventilation (two windows, or a window and a door) works best. A fan pointed out the window helps pull air through.
5. Leave the bed uncovered for a while if you can. If the smell bothers you, give it the first day without sheets, then put on a mattress protector and sheets.
6. A warm room helps. Foam expands more easily when it isn’t cold, and you’ll be more willing to keep a window cracked in a comfortable room.
7. Try baking soda if it lingers. Sprinkle a thin layer over the surface, leave it a few hours, then vacuum it up well. It’s a dry method, so it won’t soak the foam. Our how to clean a mattress guide covers it step by step.
8. Wash the cover if your mattress has a washable one and the fabric is what you smell. Many of ours have a zip-off machine-washable cover; follow its care label (cold, gentle cycle, air dry without heat, per the listings).

What not to do

• Don’t soak it. Heavy fabric sprays, steam cleaners and wet scrubbing push moisture into the foam. The care instructions say not to steam it or let moisture saturate the mattress, and liquid damage isn’t covered by the warranty.
• Don’t cover the smell with scented sprays on the mattress itself. Fresh air does the job.
• Don’t stand or jump on it to “speed up” expansion. The care instructions say not to, and body heat from sleeping on it does the job.

What our listings say about the foam: CertiPUR-US

Most of our mattress listings carry this certification statement, word for word:

“CertiPUR-US certified. Certified foams are made without formaldehyde, phthalates, ozone depleters, heavy metals, PBDEs, or the following Tris flame retardants: TCEP, TDBPP, TDCPP, or TEP. The foam is low VOC (Volatile Organic Compound) emissions for indoor air quality. Visit certipur.us for more information.”

CertiPUR-US is a certification program for the foam itself. It’s about what the foam is made without and its emissions; it doesn’t mean a new mattress will have no smell at all. For the details of the program, see certipur.us.

Here are the 23 of our 26 mattresses whose listings state a CertiPUR certification today, cheapest queen first:

Prices are today’s prices, read live from our catalog, with free shipping included; a dash means that size is sold out today. Certification wording is read from each product listing. Don’t see a model here? Its listing doesn’t state a certification, so text John and he’ll find out for you.

Plant-based foam and odor-fighting layers

• Soy-based foam: our EcoCore mattresses (10" EcoCore Origin, 10" EcoCore Hybrid Premium and 12" EcoCore Hybrid Deluxe) are made with bio-based foam derived from soy, which their listings call a renewable resource. They also list the CertiPUR-US statement. They can still have a light new smell when first opened, like any foam.
• Bamboo charcoal: the 10" Allureluxe Hybrid and 14" Allureluxe Classic listings describe their bamboo charcoal memory foam as having odor and moisture-wicking properties. That’s about everyday freshness over the years, not the first-day smell. More in our gel vs copper vs charcoal memory foam guide.

New foam pillows can smell too

A memory foam pillow that ships compressed can have the same light new smell. Unwrap it, let it air out in a ventilated room for a few hours, and wash the cover per its label if it has a zip-off one. These foam pillows list CertiPUR-US or CertiPur certified foam:

• Ventilated Copper Infused Memory Foam Pillow with Washable Cover: from $65 today
• Ventilated Bamboo Charcoal Infused Memory Foam Pillow with Washable Cover: from $63 today
• Bamboo Charcoal & Cooling Gel Memory Foam Pillow with Washable Cover: from $70 today
• Cooling Contoured Side Sleeper Shoulder Pillow: from $60 today
• Cryo-Chill Cooling Phase Change Memory Foam Pillow: from $75 today
• Reactive Shredded Memory Foam Pillow with Adjustable Loft Height: from $77 today

Picking one? Our how to choose a pillow guide matches pillow height to how you sleep.

Keeping it fresh after the first week

• Use a protector from the first night you make the bed. It keeps sweat and spills out of the foam; see do you need a mattress protector.
• Wash the cover and protector on a schedule, following each care label.
• Rotate it head to foot every few months, as the care instructions suggest.
• Pets on the bed? Our mattress for dog and pet owners guide covers hair, accidents and covers.

10" EcoCore Origin Soy-Based Memory Foam Mattress - Medium Firm

Medium-firm all-foam made with soy-based foam, a renewable resource, per its listing.

• 2" bio-based (soy) air foam
• Air Channel base for airflow
• CertiPUR-US certified foam (per the listing)
• Zip-off machine-washable cover

From $349 (Twin XL) · Queen $599 · See sizes & details

10" Allureluxe Hybrid Advanced Cooling Mattress with Lumi Bands - Medium Firm

A medium-firm hybrid with bamboo charcoal memory foam and graphite cooling bands.

• Bamboo charcoal foam with odor and moisture-wicking properties (per the listing)
• Pocketed coils with an Air Grid layer
• CertiPUR-US certified foam (per the listing)

From $589 (Twin XL) · Queen $889 · See sizes & details

Questions we hear a lot

Questions? Just ask us

If your new mattress still smells strong after about a week, or you want to know about a specific model before you buy, text or call John at 818-924-3744, 6 AM to 9 PM Pacific. Still shopping? Start with our how to choose a mattress checklist or the 60-second mattress quiz. See our Purchase Policy & Warranty for the details.

Written by John & Mimi Venti, MimiJohn. Expansion times, care instructions and certification wording are quoted from the product listings on this site; smell timing is a typical range, not a guarantee. General guidance, not medical advice. Prices are read live from our catalog and update automatically.