✓ Quick answer
To air out a new mattress faster, unbox it in a well ventilated room, remove all plastic immediately, and place a fan facing the mattress for 2 to 4 hours. Open windows and keep the room dry. This cuts typical off gassing time from 24 72 hours down to a few hours.
Why it happens
New mattresses, especially memory foam and hybrid models, release volatile organic compounds (VOCs) from the manufacturing process. This is not dangerous for most people, but the smell can be strong for the first few days. The foam cells also need time to expand fully after being compressed in a box. Trapped air and packaging materials slow down both the off gassing and the expansion process.
How to check
- Smell test: if you can detect a chemical or plastic odor when you put your nose near the surface, the mattress still needs airing.
- Visual check: look for low spots, uneven edges, or areas that feel firmer than others. A mattress that has not fully expanded will have visible dips.
- Height measurement: measure the mattress height at the center and compare it to the manufacturer’s listed spec. If it is more than an inch short, it needs more time.
What to do
Follow these steps in order for the fastest results.
- Remove all packaging immediately. Cut the plastic wrap off as soon as the mattress is on the foundation. Do not let it sit in the plastic for hours.
- Place the mattress on a firm, flat base. A slatted foundation or box spring works best. A soft surface like the floor can block airflow underneath.
- Open windows and doors. Cross ventilation is the most effective way to clear out VOCs. If weather permits, open two windows on opposite sides of the room.
- Point a fan directly at the mattress. A standard box fan or standing fan on medium speed aimed at the top surface will move air across the foam. Leave it running for 2 to 4 hours. For stronger smells, run it overnight.
- Flip or rotate the mattress after two hours. This exposes the bottom side to airflow and helps the mattress expand evenly. Most mattresses can be rotated but not flipped; check your model.
- Keep the room temperature above 70 degrees Fahrenheit. Warm air helps foam cells expand faster. Cold rooms can delay expansion by 12 to 24 hours.
- Wait at least 4 hours before putting on sheets. Sheets trap moisture and slow down the remaining off gassing. If the smell is mild, you can sleep on it after 4 hours with a well ventilated room.
If you need to use the mattress sooner, some brands allow sleeping on it before it fully expands. Read our guide on whether you can sleep on a mattress before it fully expands to know what to expect.
Common mistakes
- Leaving the plastic on overnight. This traps VOCs and can cause the foam to expand unevenly.
- Putting sheets and mattress protectors on too early. These block airflow and can make the smell linger for days.
- Closing the room door. A closed room concentrates the smell and slows ventilation.
- Using scented candles or sprays to mask the odor. These add extra chemicals to the air and do not remove VOCs.
- Placing the mattress in direct sunlight. UV rays can damage foam and cause discoloration. Indirect light is fine.
When a new mattress makes sense
If you are replacing an old mattress that is over eight years old, sagging, or causing poor sleep, a new mattress is a smart investment. Airing it out is a one time chore. For those who are very sensitive to smells, consider a best memory foam mattress with CertiPUR US certification, which limits VOCs. If you prefer no off gassing at all, a latex or hybrid mattress typically has a much shorter airing period. See our mattress types guide to compare materials before buying.
| Material |
Typical airing time (with fan) |
Strong smell? |
| Memory foam |
2 to 6 hours |
Yes, moderate |
| Latex |
30 minutes to 2 hours |
Mild, rubbery |
| Hybrid (foam + coils) |
1 to 4 hours |
Mild to moderate |
| Innerspring |
30 minutes to 1 hour |
Minimal |
Frequently asked questions
Can I sleep on my new mattress the first night?
Yes, if the room is well ventilated and the smell is not overwhelming. Most people can sleep on a memory foam mattress after 4 to 6 hours of airing. If you are sensitive to smells, wait 24 hours. Check our article on mattress break in time for more details.
Does baking soda help air out a mattress faster?
Baking soda can absorb odors on the surface, but it does not speed up the release of VOCs from inside the foam. It is not a substitute for airflow. If you want to try it, sprinkle a thin layer on the mattress after the first airing, wait 30 minutes, then vacuum it off.
Why is my mattress not expanding after 24 hours?
Cold temperatures are the most common cause. Move the mattress to a warmer room or raise the thermostat. If it still has not expanded after 48 hours, check for a defect. Read our guide on memory foam mattress not expanding for troubleshooting steps.