Peppermint Oil for Ants: Does It Work and How to Use It Safely

TL;DR

• Peppermint oil can repel ants, but usually only for a short time and only where you apply it. It does not reach the colony hidden in your walls or yard.
• Put away food first, wipe the ant trail with soapy water, then apply peppermint oil at the entry point where the ants get in.
• Refresh it every few days, after every cleaning and as soon as you see ants again. Essential oils evaporate quickly.
• Take care with cats and babies. Mint oils are toxic to pets, and inhaling menthol can cause breathing problems in infants and young children (Texas A&M, NCCIH).
• Ants coming back every day? Switch to a slow-acting bait that workers carry back to the nest, where it can kill the whole colony, queens included.
• Need help? Get a quote from a recommended local exterminator through Pest Agent's referral form.

Peppermint oil for ants appeals to anyone who would rather not spray insecticide next to the toaster. A few drops on the windowsill smell fresh to you and unpleasant to the ants, and that is the whole appeal. The colony feeding those workers sits in a wall void or under the patio, though, and no scent on a windowsill reaches it.

Natural does not mean harmless either: mint oils, peppermint included, are on the list of essential oils toxic to pets, with cats most at risk. Before you treat every doorway, the useful question is not whether ants dislike peppermint but how long that dislike lasts once the oil starts to evaporate.

Does Peppermint Oil Repel Ants?

Peppermint oil repels ants, but only for a short time and only where you apply it. Ants avoid surfaces that smell strongly of peppermint, so a fresh application can keep them off a windowsill or a doorway. It does not reach the colony hidden in your walls or yard, which is why peppermint oil works best as one tool among several.

What Is Peppermint Oil?

Peppermint oil is the essential oil taken from the leaves and flowering parts of the peppermint plant, a natural cross between water mint and spearmint, according to the US National Center for Complementary and Integrative Health (NCCIH). Its main active compound is menthol, which gives it the sharp, cooling smell that many people like and ants tend to avoid.

How Does Peppermint Oil Affect Ants?

Peppermint oil affects ants through their sense of smell. According to Health Canada, ant colonies send out scouts, and a scout that finds food leaves a scented trail for other workers to follow back to it. A strong smell like peppermint makes a treated spot unattractive, so ants avoid it or walk around it. Peppermint oil may not erase an existing trail on its own: University of California IPM (UC IPM) says it is soapy water that removes the scent trail ants leave behind.

What Does the Research Say?

Research shows that peppermint oil deters ants in controlled tests, but there is little proof that it works in real homes over time.

• A 2024 University of Georgia study tested home remedies on Argentine ants looking for a moist shelter. A 1% peppermint oil solution was reportedly the most deterrent of all the treatments: on average, almost no ants went into the treated shelter, versus most ants in shelters treated with plain water. Popular remedies such as tansy leaves, cucumber peel and soybean water reportedly did nothing.
• A 2020 study in the Journal of Economic Entomology reported that a 10% peppermint oil dip kept colonies of the European red ant (Myrmica rubra) from nesting in treated pots. This invasive ant, also called the European fire ant, appears to be spreading in Canada, especially in British Columbia, and it can sting when disturbed.
• Extension experts are cautious. A University of Nebraska-Lincoln extension educator notes that most studies on peppermint oil and ants happen in a laboratory with mixed results, and that it may work as part of an integrated pest management plan, not as a standalone fix.

The University of Georgia tests reportedly lasted only 2 and 4 hours, on a single ant species. The lead researcher said he could not promise anything after those four hours.

How Long Does Peppermint Oil Keep Ants Away?

Peppermint oil keeps ants away for hours to days, depending on how strong the mixture is. In a 2012 study on Argentine ants, a weak 0.10% peppermint solution reportedly no longer repelled ants after 7 days, while stronger 1% and 10% solutions still did. The University of Georgia researchers add that essential oils can evaporate quickly, so repeat applications are often needed, and UC IPM notes that plant oil products have limited residual activity against ants. In practice, plan to refresh peppermint oil every few days and after every cleaning, and as soon as you see ants again.

How Do You Use Peppermint Oil for Ants?

Peppermint oil for ants works best as a scent barrier at the exact spots where ants get in, refreshed often. Follow these steps in order, because the scent alone cannot compete with an open bag of sugar.

Remove Food Sources First

Removing food sources is the step that makes every repellent work better. Health Canada recommends storing sweet and greasy foods in glass jars with rubber seals or containers with tight lids, wiping counters, sweeping or vacuuming often (especially around pet dishes), rinsing containers before recycling and emptying kitchen garbage often. You can also set your pet's food bowl in a shallow dish of water, since ants cannot cross it. Our guide to getting rid of ants in the kitchen covers this room in detail.

Find the Entry Points

Finding the entry points tells you where to put the peppermint oil. Watch a trail of ants and follow it back to where it starts: a gap under a door, a cracked window frame, a hole around a pipe or a crack in the baseboard. Treating that spot is far more useful than spraying the whole room.

Peppermint Oil Spray

A peppermint oil spray is the simplest way to cover a doorway or a windowsill. Mix a small amount of peppermint oil into water in a spray bottle, shake well before each use (oil and water separate), and mist the entry points and the edges of the ant trail. No authority we found publishes a tested household recipe: the studies that found a repellent effect used solutions of about 1% or stronger, and weaker mixtures tended to fade within a week.

A few precautions:

• Test the spray on a hidden spot first, since oils can mark some surfaces.
• Do not spray food, dishes or food prep surfaces.
• Do not spray where cats spend time, or near ant baits.
• Refresh the spray when the smell fades.

Peppermint Oil Cotton Balls

Peppermint oil cotton balls give you a longer-lasting scent spot without spraying. Put a few drops of peppermint oil on a cotton ball and tuck it near an entry point, inside a cabinet where ants come in or under the sink. Keep cotton balls out of reach of children and pets, who might chew or swallow them, and replace them as soon as the scent fades.

Wiping Ant Trails

Wiping ant trails with soapy water removes the scent ants follow, and it is the step most people skip. UC IPM recommends cleaning up invading ants with a sponge and soapy water as soon as they come in, especially at entry points, and notes that vacuuming or mopping a trail can work as well as an insecticide spray to remove foraging ants for a while. Once the trail is clean and dry, add your peppermint oil to the entry point so returning scouts meet the scent.

Store-Bought Peppermint Ant Sprays

Store-bought peppermint ant sprays are an option if you prefer a ready-made product. UC IPM explains that plant oils such as peppermint, rosemary, clove, orange and thyme are used in ant products, and that they usually kill ants on contact but do not last long on surfaces. Many peppermint sprays sold online are American products. Before you buy one in Canada, check that the label shows a PCP (Pest Control Products) registration number and lists ants, as Health Canada recommends. For ready-made options, see our picks for the best ant killer.

Is Peppermint Oil Safe Around Pets and Children?

Peppermint oil is natural, but natural does not mean safe for everyone in your home. Use it in small amounts, keep bottles closed and out of reach, and take extra care if you have cats or a baby.

Cats and Dogs

Peppermint oil can harm pets, and cats are most at risk. The Texas A&M College of Veterinary Medicine lists mint oils, including peppermint, among essential oils that are toxic to pets. Cats inhale oil from diffusers and swallow droplets that settle on their fur when they groom. Watch for a watery nose or eyes, drooling, vomiting or difficulty breathing. If your cat seems distressed, move it to fresh air right away and call your veterinarian, and get emergency veterinary care if it does not recover quickly. If you have pets, read our guide to pet-safe ant killers and ask your vet before using essential oils at home.

Babies and Young Children

Peppermint oil should not be used on or near the face of babies and young children. NCCIH warns that inhaling menthol can cause breathing problems in infants and young children. Keep bottles and treated cotton balls out of reach, and do not spray peppermint oil in a nursery.

Skin Irritation

Peppermint oil can irritate the skin. NCCIH notes that it can cause skin rashes and irritation, and in rare cases allergic reactions. Wear gloves when you handle the pure oil and wash your hands afterwards.

Houseplants

Peppermint oil can damage houseplants. Pest professionals warn that oil sprayed on leaves can scorch them, especially in heat and sun. Spray around the pot or the windowsill rather than on the plant itself, and test one leaf first if you must.

Homemade Mixtures in Canada

Homemade peppermint sprays are not registered pest control products in Canada. Health Canada warns that homemade pesticides are not scientifically tested for safety or effectiveness and come with no label directions. A light peppermint scent at a doorway is a low-risk choice, but for anything stronger, Health Canada advises using a registered product with a PCP number and following its label.

When Is Peppermint Oil Not Enough for Ants?

Peppermint oil is not enough when ants keep coming back, because it moves ants around rather than destroying the nest. These are the situations where you need a different approach.

Peppermint Oil Does Not Kill the Colony

Peppermint oil does not kill the colony, so the queens keep producing new workers. UC IPM explains that sprays kill only the foraging ants you see, not the colony and its queens. Slow-acting baits work differently: worker ants carry the bait back to the nest, where it can kill the entire colony, queens included. If you see ants every day despite peppermint oil, move on to the steps in our guide on how to get rid of ants.

Repellents Next to Ant Baits

Repellents next to ant baits work against you. Baits only work if ants walk to them, eat and carry the bait home. UC IPM advises against using any insecticide sprays while you are using baits, and a strong peppermint scent beside a bait station can keep ants away from it. If you use baits, keep peppermint oil for entry points in other rooms, or skip it until the baits have done their job.

Pharaoh Ants

Pharaoh ants are the one species where peppermint oil can make things worse. These tiny yellowish ants usually live indoors in colonies with many queens, and UF/IFAS warns that repellent products can make their colonies bud, meaning they split into several new nests. If you see tiny pale ants in several rooms, read our guide to pharaoh ants before you use any repellent.

Carpenter Ants

Carpenter ants need more than peppermint oil. Health Canada notes that they are usually larger than other ants and can damage wood structures. Peppermint oil may turn them away from one spot, but it does nothing to the nest inside your walls or deck. Our guide on how to get rid of carpenter ants explains how to find and treat the nest.

Sealing Cracks

Sealing cracks gives a lasting barrier that peppermint oil cannot. UC IPM recommends caulking cracks and openings that let ants into buildings, and Health Canada suggests sealing cracks in foundations and walls and caulking indoor gaps. Do this once the ants are gone, and peppermint oil becomes a light extra layer instead of your only defence.

When to Call a Pest Control Professional

Calling a pest control professional makes sense when you find carpenter ants, when ants are in several rooms, or when weeks of baiting and cleaning have not stopped them. A licensed professional can identify the species, find the nest and choose a treatment that reaches the colony. You can get a quote from a recommended local exterminator through Pest Agent's referral form.

What Is the Best Natural Ant Repellent Besides Peppermint Oil?

The best natural ant repellent depends on what you need: keeping ants away from a spot, killing the ones you see, or reaching the nest. Here is how the most common options compare with peppermint oil. With peppermint oil, ants are only deterred, so pair any of these with good food storage.

Diatomaceous Earth

Diatomaceous earth is a powder that Health Canada lists as a non-chemical option for ants. You place it in cracks and crevices, and it is non-toxic to people and pets, although you should avoid breathing in the dust. Unlike peppermint oil, it acts on the ants that cross it. See our guide to diatomaceous earth for ants.

Vinegar

Vinegar is often used the same way as peppermint oil, to wipe ant trails and deter ants for a while. For removing trails, soapy water is what UC IPM recommends. Our guide on whether vinegar kills ants explains what vinegar can and cannot do.

Cinnamon

Cinnamon is a popular kitchen remedy for ants, but like most spice remedies it has little research behind it. Our guide to using cinnamon for ants explains how people use it and its limits.

Lavender Oil

Lavender oil is another essential oil people use against ants, and the Texas A&M veterinary list of oils toxic to pets includes lavender too, so the same cat warning applies. Read more about lavender against ants.

Fresh Rosemary and Spearmint

Fresh rosemary and spearmint leaves reportedly deterred ants in the same 2024 University of Georgia lab study that tested peppermint oil. The researchers call for field trials before drawing firm conclusions, but a pot of fresh herbs near a doorway is a harmless experiment. For options that actually kill ants, see our guide to homemade ant killers, and browse all our ant guides.