How to Get the New Mattress Smell Out (Off-Gassing)

By MattressDealsOnline Editorial · Updated July 2026

Open a new foam mattress and you'll often notice a distinct chemical smell. This is off-gassing: volatile organic compounds (VOCs) that were trapped in the foam during manufacturing and compression escaping into the air now that the bed can expand. It's a normal, generally harmless process, and the smell fades on its own - but a little ventilation clears it much faster. Here's what's happening and how to get rid of it quickly.

What causes the smell

The smell comes from the foams and adhesives used to build the mattress. During production and especially during the vacuum-compression that lets a mattress ship in a box, VOCs get sealed inside the material. When you unwrap the bed and it decompresses, those compounds release and you smell them. This is why bed-in-a-box memory foam mattresses off-gas the most - they've been tightly compressed for days or weeks - while latex and innerspring beds off-gas far less. It's a manufacturing byproduct, not a sign of a defect or a low-quality bed.

How long it lasts

For most mattresses the smell is strongest right out of the box and fades noticeably within a few hours to a few days. With good ventilation, many beds are essentially odor-free within 24 to 48 hours. A faint smell can linger up to a week in a poorly ventilated room. If a strong odor persists beyond about two weeks despite airing the bed out, that's unusual - contact the retailer, as it may point to a problem with that particular unit.

Is off-gassing harmful?

For the large majority of people, no - the VOCs released are at low concentrations and cause, at most, temporary irritation: a headache, a stuffy nose, mild throat or eye irritation that passes as the smell clears. The compounds dissipate quickly and aren't considered a lasting health risk at these levels. A few honest caveats:

• Certifications limit the compounds. Look for CertiPUR-US (limits harmful chemicals in the foam) or GREENGUARD Gold (low chemical emissions). These are your best assurance that off-gassing stays in the harmless range.
• Sensitive groups should take extra care. People with asthma, chemical sensitivities, or respiratory conditions, and homes with infants or pregnant people, should ventilate thoroughly and consider airing the bed in a separate room for a few days before sleeping on it.
• Natural materials off-gas least. If off-gassing worries you, natural latex, wool, and cotton beds release far fewer synthetic VOCs. Our memory foam vs latex guide covers the natural-material option.

How to get the smell out fast

Airflow and warmth are what clear off-gassing. Do these in order:

• Unbox in a well-ventilated room. Set the mattress up somewhere with airflow the moment you unwrap it, ideally not the room you'll sleep in that first night. Open windows.
• Move air across it. Open windows, run a fan pointed at the bed, or use a bedroom air purifier. Cross-ventilation dramatically shortens the process.
• Give it 24-72 hours before dressing the bed. Let the bare mattress breathe before adding sheets and a protector, which would otherwise trap the odor in.
• Use baking soda. Sprinkle a light, even layer of baking soda over the surface, leave it several hours (a full day if you can), then vacuum it off. Baking soda absorbs odors and residual moisture.
• Add gentle warmth. A slightly warm room helps the VOCs release and dissipate faster. Sunlight and fresh air help too if you can air it near an open window.

What to avoid: don't spray perfumes or heavy air fresheners directly on the foam to mask the smell - you're just adding chemicals on top, and moisture can harm the foam. Let ventilation do the work.

Minimizing off-gassing next time you buy

If you're sensitive to it, you can reduce off-gassing before it starts by choosing the right bed: prioritize CertiPUR-US or GREENGUARD Gold certified foams, favor latex or innerspring construction over compressed all-foam, and where possible buy a bed that isn't shipped compressed. Planning to unbox a few days before you actually need to sleep on it also gives it time to clear with zero effort. And once the smell is gone, it's gone - off-gassing is a one-time event at the start of the mattress's life, not an ongoing thing.

Beds we've tested

FAQ

How long does new mattress smell last?

Usually a few hours to a few days, and rarely more than a week. Airing the bed out in a ventilated room speeds it up. If a strong smell lingers past two weeks, contact the retailer.

Is off-gassing from a mattress harmful?

For most people the VOCs released are at low levels and cause at most temporary irritation like headaches or a stuffy nose. Certified foams (CertiPUR-US) limit the compounds involved. Those with chemical sensitivities or asthma should ventilate thoroughly and consider natural materials.

How do I get the smell out fast?

Unbox it in a well-ventilated room, open windows or run a fan, give it 24 to 72 hours before adding bedding, and sprinkle baking soda on the surface then vacuum it off. Warmth and airflow are what clear it.

Which mattresses off-gas the least?

Latex and innerspring beds off-gas the least. Memory foam and bed-in-a-box foams off-gas most because they are compressed. Look for CertiPUR-US or GREENGUARD Gold certification to minimize it.