Why does my mattress smell?

Your bedroom should be inviting and restful, but if unpleasant odours from your mattress are affecting your sleep it’s time to take action.

From natural body odours to musty smells and chemical gases, a mattress can often be the culprit when it comes to a smelly bed.

Thankfully, most mattress smells are easily remedied, so you may not have to buy a new one just yet. Check to see if your mattress is due an upgrade with our helpful ‘How often should you change your mattress’ and ‘How to choose a mattress’ guides.

If you’re sticking with your current mattress for now, there’s a few tips and tricks you can try to get it smelling fresh. Read on for our troubleshooting guide that will have you sleeping soundly again in no time.

Why does my mattress smell?

Liz Wegener, head of owned brand development at Bensons for Beds explains that some mattress odours are to be expected. “We sleep on our mattresses for several hours every night, so they’re bound to get slightly grotty after a while and, over time, your mattress can start to whiff,” she says.

There are three main causes of mattress odours:

• Chemicals – This type of smell is common after unpacking new memory foam mattresses and is caused by “off-gassing” (see below).
• Sweat and dirt – A musty, stale odour due to lack of cleanliness. Need to clean yours? Read our ‘How to clean a mattress: Tips, tricks and our pick of the best stain protectors, hoovers and stain removers’ guide.
• Mould – This “damp” smell is commonly caused by poor ventilation.

READ NEXT: Emma Original vs Simba Hybrid: Which is better?

What is off-gassing?

If you’ve invested in a new memory foam mattress then you may find it gives off a faint, unpleasant chemical smell once unpacked. As memory foam is made from a dense visco-elastic foam, volatile organic compounds (VOCs) are released in vapour form (known as “off-gassing”) when first released from vacuum packaging.

But if that sounds slightly disturbing, there’s no need to worry. The Sleep Foundation says, “Off-gassing odours pose no known serious health risks”. Read more about VOCs in our longer explainer ‘What is memory foam?’.

How to eliminate chemical smells from mattresses

“Many new mattresses have a distinctive aroma, similar to when you buy a new leather jacket and this smell will disappear over time,” Liz explains. “These gasses are completely harmless to people and animals. Simply airing the mattress once it arrives will allow any trapped gasses to disperse, and any odour will quickly disappear over the next few days.

“It’s always good to remember that our sense of smell is subjective, so what someone identifies as a bad smell might not be the same to someone else.”

In our best mattress type test, we found that the Nectar mattress had “minimal odour after unpacking” and offered “excellent levels of comfort and support”. Read our full Nectar review for more information.

How to eliminate sweaty, stale smells from mattresses

“When you sleep, you tend to sweat, which can soak through your bedsheets into your mattress,” Liz explains.

It’s important to maintain good hygiene and Liz advises regular cleaning.

“Clean your mattress by lightly brushing its surface to remove dust, dirt and allergens. For spot cleaning, use a mild detergent or upholstery cleaner diluted in water and blot the affected area gently,” she explains.

“You can also sprinkle the top of your mattress with a small amount of baking soda. This helps to get rid of smells which have soaked in. Leave the baking soda for as long as possible before brushing off the excess.”

Another solution would be to use a mattress protector.

“A waterproof and breathable mattress protector can help protect your mattress from spills, stains and odours caused by sweat and body oils. It also creates a barrier between the mattress and external contaminants, helping to keep it clean and fresh,” Liz explains.

If you’re a hot sleeper, consider purchasing a cooling mattress next time you’re looking for a replacement. We awarded the Simba Hybrid Pro the best cooling mattress bed-in-box in our best cooling mattress roundup.

How to eliminate mouldy, damp smells from mattresses

This is trickier as it tends to be caused by your bedroom’s environment, which isn’t always something you can easily control. If it’s too humid (damp) due to excessive moisture in the air, you’ll have a problem.

“Allow for adequate ventilation and ensure proper airflow around the mattress by using breathable bedding, rotating the mattress and avoiding excessive moisture buildup in the bedroom,” Liz advises.

You should avoid drying your laundry in your bedroom if damp or excess humidity is an issue. Using a dehumidifier can restore the moisture balance in the air (as well as help dry your laundry). We rated this £140 VonHaus model great for smaller homes. Also check that any food (or drink) spills haven’t been left to fester and turn mouldy.

For an extra helping hand consider replacing your current mattress with the Otty Pure Hybrid Bamboo & Charcoal Mattress which has a bamboo and charcoal memory foam layer with antibacterial properties. When reviewed, we found it naturally wicked away moisture and odour, and was very comfortable for back and side sleepers. Otty also sells a charcoal memory foam mattress topper if you prefer to keep your original mattress.

Finally, don’t forget your pillows, which can also cause unpleasant odours. Keep them smelling box-fresh with our ‘How to wash pillows’ guide.