Mice and rats rely on their highly developed olfactory receptors to find food, detect predators, and communicate with each other. However, this heightened olfactory prowess is a double-edged sword. While it is generally advantageous, that is not always the case.
For mice and rats, certain smells are not just unpleasant—they are downright so unbearable that they would rather turn tail and flee.
Understanding these aversions can be a game-changer in your ongoing battle to keep these rodents away. So, which smells do mice and rats hate? Find out below.
20 Smells That Mice and Rats Hate
1. Peppermint
We humans revel in the minty freshness and invigorating scent of peppermint, but mice and rats have a completely different reaction to it. Peppermint is overwhelmingly strong and unpleasant to these rodents, bombarding them with an intense aroma, which then irritates their nasal passages.
A potent peppermint oil works best at repelling mice and rats, so use pure, undiluted peppermint oil. Leave peppermint oil-soaked cotton balls in areas these rodents frequent.
2. Ammonia
A rat or mouse’s respiratory system cannot handle the sharp, acrid smell of ammonia—it is like a sensory overload for them. Ammonia mimics a predator’s urine scent, which naturally scares away rodents. Many household cleaning products contain ammonia.
Place ammonia-filled bowls or dishes where you suspect rat and mouse activity, like nesting sites or along paths. Alternatively, you can soak cotton balls in ammonia.
3. Eucalyptus
Eucalyptus has an unmistakably potent and overwhelming aroma that is offputting to mice and rats. Some humans also find it unpleasant. Eucalyptus oil is an excellent mouse and rat repellent because it contains the highest concentrations of eucalyptol.
Soak several cotton balls in eucalyptus oil and place them strategically. You can also make eucalyptus spray by mixing eucalyptus oil with water to spray rodent-prone areas.
4. Garlic
The taste and smell of garlic, including the plant, repulse mice and rats. Garlic contains compounds like allicin, which can be quite pungent and irritating to their sensitive noses and taste buds. This makes areas with garlic less attractive to mice and rats.
Place garlic cloves in areas where these rodents are likely to enter your home, and they will be less likely to stick around.
5. Chili Powder
Next on the list is a spicy smell. In general, chili powder, chili oil, and hot sauce are among the odors that mice and rats hate because chili’s active ingredient, capsaicin, irritates their mucous.
When they come into contact with chili products, it causes discomfort in their olfactory glands and a burning sensation in the taste buds. Sprinkle chili powder around entry points, nests, or areas where you’ve seen rodent activity.
6. Onions
Ah, the onion—a vegetable that makes us cry but adds depth and complexity to dishes with its sweet, pungent scent. Onions are the kitchen’s unsung heroes, but there’s more: mice and rats dislike their smell.
When an onion is sliced open, it releases propyl sulfoxide that irritates a mouse or rat’s eyes and nasal passage. Place sliced onions near mice and rats’ entry points or nesting sites.
7. Mothballs
This old-school method of repelling moths also works on mice and rats as it produces a strong, penetrating smell. In addition, mothballs have active ingredients such as naphthalene and paradichlorobenzene that are toxic to animals as well as humans.
Due to mothballs’ toxicity, always be careful when handling it for your sake, the environment, and your pets. Don’t use mothballs where you prepare or store food.
8. Cloves
The primary compound in clove oil, eugenol, has a potent scent that disrupts rodents’ sensitive olfactory senses, making their environment unpleasant. This overwhelming smell masks other odors that attract them and creates a hostile atmosphere.
Clove oil can help you discourage mice and rats from establishing residence in your home with clove oil’s help. Use cotton ball-soaked clove oil or crush dried-up clove flower buds to release the scent.
9. Citronella
Citronella, a renowned insect repellent with a fresh, lemony scent, is hated by mice and rats. The strong, citrusy scent of citronella oil is unpleasant to them. Like with insects, citronella disrupts their sense of smell and makes the environment less inviting.
When it comes to using citronella to keep mice and rats away, use the oil or spray. Avoid citronella candles because it doesn’t do much to these rodents.
10. Citrus
Rats and mice tend to steer clear of areas with an intense citrus smell, especially from lemons, limes, and oranges. Therefore, you can create an environment that deters these rodents using citrus peels, citrus oil sprays, or citrus-soaked cotton balls.
Citrus essential oils work best, especially in concentrated and pure forms. On the flip side, citrus juice may not be as overpowering. Besides being an effective repellent, citrus also smells great.
11. Bleach
Any area that reeks of ammonia isn’t a place a mouse or rat wants to be. If these rodents sniff ammonia, it irritates their noses and eyes and overpowers their respiratory systems.
So, if you’re trying to discourage these critters, a hint of ammonia might just send them scurrying for the nearest exit. Use ammonia cautiously since it can damage some surfaces and cause staining, skin irritation, and eye discomfort.
12. Vinegar
For rats and mice, vinegar’s sour scent overwhelmingly assaults their senses. In addition, the strong smell masks other scents that these rodents rely on to navigate and find food. A concentrated vinegar is best, as a diluted form may be less effective.
Use vinegar in moderation because the overpowering smell from too much vinegar can become unpleasant.
13. Black Pepper
Black pepper contains piperine, which produces a pungent and irritating odor that can overwhelm rats and mice. The strong scent causes discomfort in their nasal passages, leading them to avoid areas where black pepper is present.
To use black pepper as a deterrent, sprinkle it around the areas you want to protect, such as entry points. To enhance its potency mix black pepper with cayenne pepper or essential oils.
14. Sage
Sage, particularly its essential oil, has a strong, distinctive aroma that rodents find unpleasant. Rats and mice generally avoid places that smell of sage, both white and green varieties.
Scatter dried sage leaves or place small sachets of dried sage in areas where you have a mouse or rat problem. Strategically positioning sage essential oil-soaked cotton balls will also help deter these rodents.
15. Lavender
Lavender is more than just a beautiful purple flower. It is also an edible flower, a pleasant scent for detergents, and perfumes, a great mood booster, and mice and rats hate its smell.
Lavender’s aroma can be overwhelming for these pests. Repel rats and mice naturally with lavender by placing lavender oil-soaked cotton balls where these rodents like to roam.
16. Cinnamon
The compounds in cinnamon, particularly cinnamaldehyde, can irritate the nasal passages and respiratory systems of rats and mice. Stash some cinnamon sticks, sprinkle cinnamon powder, or burn cinnamon sticks around your home to deter unwanted mice and rats.
Cinnamon can help you keep these rodents out of your closets, drawers, underneath furniture, and even drawers. Combining cinnamon oil with peppermint oil will give you a much stronger rodent repellent.
17. Predator Urine
Mice and rats are vulnerable to many predators, from cats, birds of prey, dogs, coyotes, snakes, and foxes to weasels. These rodents use their sense of smell to perceive and avoid their enemies.
The scent trails left by predator urine are enough to have them running for the hills. The strong, lingering scent serves as a warning signal to rats and mice, suggesting that a predator is nearby.
18. Dryer Sheets
The unmistakable fragrance of dryer sheets is off-putting to the delicate noses of mice and rats. Dryer sheets emit a strong, synthetic scent designed to make clothes smell nice, but for these rodents, it’s a sensory overload.
The fragrances and chemicals in dryer sheets can mask the smells rats and mice rely on for survival. So, they might think twice about making your laundry room or pantry their new home.
19. Bergamot Oil
Bergamot oil, derived from the peel of the bergamot orange, has a distinctive aroma that a lot of us love for its uplifting and calming properties. However, this same scent is overpowering for mice and rats and quite different from the earthy, musty smells they prefer.
Applying bergamot oil in key areas should convince rats and mice that your home is no place for them.
20. Cedar
Cedar is renowned for its sweet, strong, refreshing scent. While pleasant to most, rats and mice dislike it. Incorporate cedarwood blocks, chips, or shavings in areas prone to mice and rat activity, or apply cedar oil in these areas. You can even plant cedar hedges around your home.
Final Remarks
While some odors such as meat, bird seed, sweets, and cheese attract rats and mice, leading them straight to your home, others are repulsive. The smells listed above, from the sharp tang of peppermint to the earthy notes of cedarwood, are unpleasant to them. By integrating these natural deterrents into your mouse and rat control strategy, you can protect your home in a way that is safe, humane, and surprisingly simple.
I’m Mike Hyle, an exterminator with 7+ years of experience handling all sorts of pests, including mice, cockroaches, bed bugs, and termites. I also write for Pest Solutions DIY blog to share my knowledge and help homeowners keep their homes pest-free. Outside work, I enjoy hunting, snowshoeing, and exploring nature. Check out my blog for helpful pest control tips!