Dead Rat / Mouse in Wall – Get Rid of them Fast! 

Updated on by Jared Belson | Please note that there may be affiliate links on this page.

There’s a sudden, unpleasant odor. Where is it coming from? What could it be? Could a dead mouse or rat be stuck inside the wall? What an awful thought!

If you suspect there is a dead rodent inside your walls, don’t panic! Keep reading to find out how to locate the rodent, and deal with the issue.

How Can I Tell if There is a Dead Rodent in the Wall?


The first clue that you may be host to a dead animal is usually the odor. As bodies decompose, they produce all kinds of gases, including methane and sulfur dioxide. These gases are the source of that toe-curling smell that is making you crazy!

Follow the odor. Try to give your home a sniff test to see if you can pinpoint where the odor is the strongest.


As the mouse or rat decomposes, it may also emit some liquid. Look for dark water stains along the walls, most likely near the floor.


Certain insects, like maggots, flies, and beetles are attracted to decomposition. Look for a high concentration of these insects along the walls.

Other Evidence of Rodents

Look for signs of a once-alive mouse or rat. This may help you figure out where they have died. Look for:

  • Small holes in the wall, floor, or baseboards.
  • Footprints near the edges of the rooms.
  • Mouse or rat droppings. If the rodent is dead, the droppings will not be fresh.

How Long Will it Smell?

The smell will eventually go away once the decomposition process is complete. This process can take one week, up to a couple of weeks, depending on the size of the animal, and the temperature and humidity levels.

Typically, the smell will become much stronger before it gets better! Then, the smell will gradually lessen before it goes away entirely.

How Do I Get Rid of the Smell?

You are probably frantic to get rid of the dead animal scent in your home! However, before you begin knocking holes into the drywall, consider all your options.

Removing the Carcass

If you feel confident that you have pinpointed the location of the dead animal, this is a great option!

  • ALWAYS wear gloves and an air-filtering mask, like an N95 mask, when dealing with rodents. Mice and rats can carry dangerous diseases.
  • Cut a hole in the area you believe the mouse or rat has died.
  • Once you have located the carcass, carefully remove it and immediately place it in a leak-proof bag.
  • Dispose of the carcass.
  • Thoroughly clean the area with a bleach solution. The Center for Disease Control (CDC) recommends one part bleach to ten parts water to disinfect areas inhabited by rodents.
  • Dispose of gloves and mask. Shower, and wash your hands thoroughly.
  • Allow the area to dry out before patching the hole.


Removing the carcass is not always an option. You may need to find an alternative way to cope with the odor until the animal has finished decomposing.

Finding the right room deodorizer may take some trial and error. Some scents combine with the odor of a rotting mouse and actually make it smell worse. Try a deodorizer like this one or this one that claims to absorb dead animal smell.

Coffee Grounds

Believe it or not, your favorite morning brew is also an odor fighter! Sprinkle coffee grounds near the area where the odor is the strongest. The coffee will help mask and absorb the odor.

Charcoal Odor Neutralizer

Charcoal is a natural and effective odor absorber! These charcoal bags can be placed around your home until the odor is gone.

Ozone Generator

An ozone generator produces ozone. The air we breathe contains two oxygen molecules. Ozone contains three oxygen molecules. This makes it unstable, and it will grab onto any polluting molecule. This will neutralize the odor.

To use an ozone generator:

  • Calculate the amount of time needed based on the square footage of the area to be neutralized.
  • Set the timer on the generator based on your calculation.
  • Leave the area. There should not be any pets or people in the area while the ozone generator is running.
  • Air out the room by opening windows or doors for 30 minutes before re-entry.
  • Repeat the process if there is any lingering odor.

How Can I Prevent a Rat/Mouse from Dying in the Walls?

Now that you have removed the rat or mouse carcass, or dealt with the odor, it’s time to figure out how to prevent rodents from dying in the walls in the first place.

Don’t Use Poison

Poison may seem like a good solution for a mouse or rat infestation. However, after the rodent eats poison, it often will go hide before it dies. This leads to dead animals in your walls. In addition, poison also poses a risk to pets and children in the home.

Set Traps

Instead of turning to poison, choose rodent traps. Set and place traps close to areas with suspected rodent activity. Bait them with nuts, seeds, peanut butter, raisins, or a combination of these treats.

Always wear a mask and gloves when handling dead rodents! Mice and rats can carry diseases and parasites.

There are many options for rodent traps. Most of them fall into one of three categories:

  1. Glue Traps use a sticky surface to trap the mouse or rat. These are easy to bait and dispose of. However, these are often viewed as inhumane because the mouse or rat will suffer while being stuck to the glue.
  2. Live cage traps are a humane way to trap mice and rats. You have the option to release the rodents far, far away, or to humanely kill them after you trap them.
  3. Snap traps, like this, or this snap shut on the mouse’s head or neck once it trips the trigger plate. These typically kill the rodent instantly and are inexpensive.

Seal Access Points

Search your home for any opening that could allow a mouse or rat access to your home. Seal any openings with caulk.

Call an Exterminator

If you have exhausted all other options, and the mice are still in your home, it may be time to call a trusted exterminator.

Final Thoughts

Dead mice and rats are a stinky problem! If you are able to locate and remove the carcass, that’s usually the best way to deal with the problem. Air purifiers or deodorizers and some patience are required if you are unable to remove the carcass.

Once you’ve dealt with the dead mouse or rat, find out how the rodents are entering your home, seal openings, and trap the remaining rodents, if any.

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