New mattress smell: What is off-gassing and how long does it last?

New mattress smell: What is off-gassing and how long does it last?
(Image credit: Getty)

Upgrading your bed is always exciting, but something that plenty of shoppers notice is that infamous new-mattress smell. Although there are many advantages to buying the best mattresses online, the smell some of them can produce when unpacked and left to expand to their full size is definitely not one of them. The smell is a byproduct of something called off-gassing, but how long can you expect it to last?  

Off-gassing can occur with many items, from the best pillows, depending on what they're made of, the best bed toppers, but it's far more noticeable with mattresses, especially those made from memory foam. Think of that new mattress smell as similar to the smell you'll experience when you buy a new car, paint your walls, or even order new clothes online. Once your new purchase is exposed to the air, as well as daily wear-and-tear, you'll release volatile organic compounds (VOCs) from the fabric or paint into the atmosphere. 

Your new car smell lasts a lot longer than the initial smell of a new sweater though, and that's because there are so many more VOCs to release and there's a higher density of fabric where they could be lurking. The same applies to your mattress, but there are a few ways to speed the process along, which we cover below. 

Don't have a new mattress yet but you're in the process of shopping for the ideal one? Then take a look at our guide to the best Purple mattress deals to save on one of the most popular bed brands in the world. Or, for a very affordable hybrid mattress, check out our round-up of the best Casper mattress deals. Want a touch of luxury? Shop the best Saatva mattress discounts and save on these chiropractor-approved mattresses.  

Why does my new mattress smell? 

So, you've bought a new mattress, and while it's incredibly comfortable and supportive, it's giving off a funny smell. Does this sound familiar? If so, there's no need to worry. The first thing you need to know is that while the smell can be unpleasant and even cause reactions for people with sensitive skin or breathing, they shouldn't be dangerous. 

When buying a bed in a box, you'll typically opt for something with at least one layer of memory foam. The trade-off with this incredibly comfortable and supportive material is its initial smell. The mattress off-gassing smell is caused by newly made chemical compounds, also known as volatile organic compounds (VOCs). 

These compounds are initially unstable elements of memory foam and mattress adhesives, and while they're not dangerous, it will take a little while for them to be released after you take your new mattress out of its box.

Is off-gassing dangerous?

New mattress smell: What is off-gassing and how long does it last?

(Image credit: Birch)

Because every mattress is different, it's hard to say for sure if your mattress' off-gassing is dangerous. However, there are a few ways to rule out any toxic chemicals and make sure it's certified as safe even as it off-gasses. 

One thing to check for is awards from air quality experts. This includes CertiPUR-US, GREENGUARD Gold and STANDARD 100 by OEKO-TEX certification. This will ensure that your mattress adheres to strict VOC guidelines to ensure your comfort and safety. 

Memory foam is a main culprit of off-gassing, but according to Amerisleep, "despite the fact that some of the chemicals that cause mattress off-gassing odors are classified as carcinogens or potential carcinogens, no studies have shown memory foam is toxic or causes cancer." 

If you've grabbed one of the best Purple mattress deals but are concerned about off-gassing, it reassures users that "we only use polyurethane foam" which is tested for VOC emissions and certified by CertiPUR-US. 

The same can be said for Casper, with the company stating: "All the foams in our mattresses are CertiPUR-US certified. They are Low VOC emissions for indoor air quality (less than 0.5 parts per million)."

How to avoid the new mattress smell

New mattress smell: What is off-gassing and how long does it last?

(Image credit: Avocado Green Mattress)

All mattresses are not made equal, and while it'll typically cost you a lot more than you'll pay for a standard memory foam mattress, opting for an organic mattress is a surefire way to cut down on VOCs and the overall smell of a new mattress. 

Some of our favorite organic mattress brands include Avocado Green Mattress, which uses organic wool, latex, and cotton and boasts class one certification from STANDARD 100 by OEKO-TEX to ensure no harmful chemicals are present.

Another organic mattress is the Saatva Classic. This mattress features recycled steel in its coils, bio-based foams, and a cover made of organic cotton. As with the Avocado Green Mattress, this is a more expensive option for those seeking a new mattress. However, the best Saatva mattress discounts may be able to help in bringing the price down. 

A final natural mattress comes from Helix mattress, which also features in our guide to the best cooling mattress. The Helix Birch mattress is made of sustainable and organic materials, and it also boasts eco-INSTITUT certification, as well as GOTS and Greenguard Gold awards. 

How long does the new mattress smell last? 

According to Amerisleep, "research has connected higher density foams with increased rates of odor complaints. Therefore brands using foam over 6.0lbs will likely smell worse." So if you have a more dense memory foam mattress with a firmer feel, the new mattress off-gassing process will last longer.

The new mattress smell can last up to a month on bulkier memory foam mattresses. Here are a few ways to speed the process along: 

How to get rid of the new mattress smell

New mattress smell: What is off-gassing and how long does it last?

(Image credit: Getty)

1. Ventilation

A new mattress needs to be placed in a room with plenty of ventilation for at least a few days. After this point most VOCs should have gone. If you've gone straight to sleeping on your new mattress without letting it breathe, strip your bedsheets and open all your windows to really allow the mattress to breathe. If you did this initially and the smell is still lingering, try flipping the mattress to allow the underside to breathe and off-gas.

2. Give your bed a massage

According to Casper mattress, giving your new bed a massage can release some of the lingering new mattress smell. One way to do this is to walk all over the mattress, which can compress areas you don't sleep on and shift anything that hasn't settled down yet.

3. Clean your mattress

We've got a lot of guidance on how to clean your mattress, but this step is typically to eliminate the buildup of oils and particles that come with prolonged use. In our guide on how to remove urine stains from a mattress, we spoke about the wonders of vinegar and water solutions topped with baking soda in shifting pesky smells. 

The same guidance applies here. Mix one part clear vinegar and one part water in a spray bottle and give your mattress a generous spritz. Dab off any excess, and then top with a sprinkle of baking soda. This will absorb odors when left for a few hours, and you can simply use a handheld vacuum to remove the excess.

Millie Fender
Head of Reviews

Millie Fender is Head of Reviews at Top Ten Reviews. She also works on our sister sites: Real Homes, Ideal Home, Homes & Gardens, and Livingetc. As Head of Reviews, Millie is on a mission to make sure that we are reviewing all of the latest and greatest products for you and your home, whether it's a vacuum cleaner or an inflatable hot tub.