How to Remove Decomposition Smell from Mattress

Leanna asked: Please help. My mattress has a lingering smell on it that I cannot get rid of. The odor smells like something decomposing. A few weeks ago, we found a dead rat in my dresser. We got it out and cleaned and sterilized the dresser, but I have been noticing a faint smell in my room. I noticed it coming from my bed. It smells like something dead. I am still paying on this mattress and cannot afford another one. What can I do?

No one wants to end a long day on a stinky mattress, but by design, a mattress can be extremely hard to deodorize. Further complicating matters is the fact that they tend to be expensive, and toss-and-replace is seldom a reasonable solution for stubborn odors. If you’ve got an unpleasant smell residing in your mattress and the usual methods for eradicating that scent aren’t doing the trick, give some of these ideas a try.

You Will Need:

  • Baking soda
  • Vacuum
  • Kids ‘N Pets Stain and Odor Remover
  • Spray bottle

Steps to Remove the Smell:

  1. Begin with a careful examination of your mattress. Remove the bedding and look closely over the entire surface, paying particular attention to the seams and side(s) that may have been against the wall. A really bad decomposition smell is unlikely to linger once the body has been carted off, so look for holes (and they might be very small) where critters could have climbed in. Use your nose as you search, and don’t forget to flip the mattress and check adjacent areas like the box springs and in any nearby containers. Just flipping the mattress may help with the smell. Remove all evidence of nests or other remnant pest invasions. An ultraviolet black light, if available can be used to find urine and other bodily fluids left by your unwelcome guests.
  2. Once you’re sure there are no deceased rodents in the vicinity, cover the bare mattress with a general dose of baking soda. Place your fitted sheet over the baking soda and leave for as long as possible. Depending on your sheets, you may be able to sleep on them with the baking soda there for a night or two.
  3. Remove the sheet and vacuum the baking soda.
  4. If the odor HAS improved, repeat steps 2-3 as often as needed. If there wasn’t a noticeable improvement, move on to step 5.
  5. Pour a cleaner designed to get rid of organic odors (which includes decomposition) in a clean spray bottle. Kids ‘N Pets works exceptionally well.
  6. Spray the cleaner over the entire exposed surface of the mattress, following the directions for application on the label.
  7. Wait at least a week after the surface dries before flipping the mattress and treating the other side.  Don’t forget about the edges. To use the mattress, make the bed at night and remove bedding in the morning. An extra blanket under the bottom sheet will keep the moisture from seeping through.
  8. If you still notice an odor, drag the mattress outside and lean it against a wall with direct sun exposure.  Flip to expose the second side after several hours. Do not do this if there are undesirable odors outside, you’ll be able to smell them on your mattress when you bring it back indoors.

Additional Tips and Advice

  • Before using any cleaners or deodorizers on the mattress, be sure to spot test in a hidden area.
  • Avoid using bleach or other strong chemicals on your mattress, especially at high concentrations.  If you get the mattress wet enough to penetrate the padding, there’s probably enough there to weaken or damage the fibers. Additionally, the chemical odor in the mattress could irritate those with respiratory problems.
  • Do NOT mix chemicals or cleaners in your attempt to deodorize your mattress.
  • If all else fails, and you can’t replace the mattress, consider a waterproof mattress pad. The plastic or vinyl barrier will help keep the smell down, while the padding helps to hide the feeling of sleeping on plastic.


  1. Wayne says:

    When you are cleaning your mattresses, it depends on how bad the odor is and how heavy the mattress. You may just need to throw it away. Otherwise you can use a sanitizer and cleaner all in one and it may do the trick.

  2. Lee says:

    I had a similar problem with a bed that was given to me by my brother. He has allergy to the ingredients in most deodorants and his skin gets irritated by water (we think it’s the chlorine and other chemicals in our tap water). The result is that the bed smelled like body odor. However, he told me to fill a humidifier with a 50/50 water + vinegar solution (half water and half vinegar), put it in a room with the bed, make sure all windows/doors are closed, turn on the humidifier, and leave the room with the humidifier on for 24+ hrs (depending on the size of the room, the smaller the better), closing the door after. You may need to check on the humidifier periodically to refill the solution inside (I didn’t, but my humidifier is on the big side). He also said if I preferred to, I could just add the vinegar water to a spray bottle and spray the bed that way, but it’s a pain because you will need to almost soak every inch of the bed. After the time is up, you remove the humidifier, open all the doors/windows, and let everything dry out for at least 1 day or if you used a closet like me, just take the bed out, put the humidifier away, and leave the closet door open for as long as necessary. If you plan to use a closet, make sure there isn’t anything that can get ruined by water though. I guess vinegar will eat/kill the germs/bacteria that cause bad smells and it even kills even most mold/fungus (I had no clue until he told me and even then I looked it up to be sure he wasn’t pulling my chain).

  3. Michelle says:

    I think we’re on the same page here…BUT…After much online research on how to deep clean a spare mattress, I’m now smelling this bleachy moldy stench!

    Going section by section, I would squirt this concoction of cleaner, scrub and then suck it up with my wet vac. Of course, the wet vac left some moisture, like it does on my carpets – but I thought my high blast fans would take care of the wetness… Sadly, a week later, I’m thinking it didn’t!

    So, now I’m stuck trying to figure out how to get that underlining bleach and mold smell out. I Febreezed it to death, but it didn’t help. I’ve used baking soda, borax, chemical cleaners, you name it! What can I do for that embedded smell? I’m considering vinegar, but ugh, that’s all I need is another stink.

    It’s driving me nuts!

    (I told my husband this is exactly why I shouldn’t be trusted to clean!)

  4. Franz says:

    A friend and neighbor of ours passed away. He lived alone and his body wasn’t discovered for at least three days after he died. His family gave us a few of his things (like a computer printer, etc.) that they knew he would want us to have. Unfortunately, everything we were given has a distinct strong smell of human decomposition. What’s the best way to get rid of that odor?

  5. Rehana says:

    Hi. A half-pint of milk fell on my foam mattress. I have dried it out in the sun for days now. I washed the mattress twice, but it only did one good thing (got rid of the milk odour), but the horrible damp odour is still lingering. Please, please help; the mattress is completely dry but the odour is still on it. I have used linen spray and still no improvement. Thank you.

  6. Melanie says:

    Try sprinkling baking soda over the mattress and letting it sit for several hours, then brushing off or vacuuming the baking soda. Baking soda is an odor remover. If the smell is not removed, you can repeat the process as many times as needed until it is gone.
    Another option is to spray the mattress with diluted white vinegar (1 part white vinegar to 4 parts water). Don’t soak the mattress, just mist it and let it dry. It is best to let it air dry, but if needed, you can use a hair dryer on the lowest setting or a fan to speed the drying time. This method can also be repeated as needed.
    If you use the above methods several times and the smell remains, it is possible that mildew has started to grow inside the foam. If that is the case, use the information in the article How to Remove Musty Smells from Furniture. However, keep in mind that you should always test a cleaning solution on a small, hidden area of your item first to ensure that there isn’t any adverse effects.
    Source: – How to Clean Foam Cushions
    Source: – How to Wash Memory Foam

  7. Linenspray says:

    My mother sweated a lot in the night and she didn’t tell me so for two nights this was happening. She does have type 2 diabetes and is on lots of heart medications. On the third day her room was reeking. I thought the cat pooed somewhere. The smell was horrible and sour-like. I washed all the floors until I realized it was coming from the bedding. I removed the bedding and still her room smelled and that is when I realized it was her mattress. I had to do something so I sprinkled baking soda all over the mattress, waited and then brushed it off. Then the real trick: I found one of those linen sprays – it was Cedar-scented, bought from Winners – and sprayed the mattress. Miraculously, the smell disappeared. I guess the spray had alcohol in it so it helped. I let it sit and then did a wipe with paper towels. I also used a bit of Windex on the paper towels when wiping down the mattress. Then it was air dried.

  8. Sandi says:

    My mattress smells. I had a herion person in my bed, sweating in my bed. I can’t get rid of the awful smell. Help!

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