Can Cats Eat Rosemary and Basil? Safety and Risks

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-10-02

Yes, cats can eat rosemary and basil in small amounts. Both herbs are listed as non-toxic to cats by the ASPCA Animal Poison Control Center [1][2]. The leaves themselves are not poisonous, but concentrated forms like essential oils and extracts can cause serious problems.

This article is educational and is not a substitute for veterinary diagnosis or treatment.

Quick Answer

• Fresh or dried basil leaves and rosemary leaves are non-toxic to cats [1][2].
• A small pinch (about a teaspoon of finely chopped fresh leaf) is plenty. Herbs are flavoring, not food.
• Never give your cat essential oils, including rosemary oil and basil oil. These are highly concentrated and can cause vomiting, wobbliness, and liver damage.
• Skip any herb preparation that contains garlic, onion, xylitol, salt, or oil blends. Those ingredients are the real danger.
• If your cat eats a lot of either herb, watch for vomiting or diarrhea and call your vet if signs appear.

Can Cats Eat Rosemary and Basil? The Short Answer

Both herbs get a green light from the ASPCA. Basil (Ocimum basilicum) is listed as non-toxic to cats and dogs [1]. Rosemary (Rosmarinus officinalis) is also listed as non-toxic to cats, dogs, and horses [2]. That means a cat who nibbles a leaf off your windowsill plant is not in immediate danger from the plant itself.

The catch is the form. A fresh leaf is not the same as a drop of essential oil. A sprinkle of dried herb is not the same as a concentrated extract. Most rosemary and basil emergencies in cats involve oils or human food products, not the plain herb.

What About Basil Leaves Specifically?

Can cats eat basil leaves?

Yes. Fresh basil leaves are non-toxic to cats [1]. Your cat can safely taste a small piece. Basil belongs to the mint family, and its scent may interest some cats more than the taste. Most cats sniff it and walk away.

Can cats eat basil plants?

Yes, the plant is non-toxic [1]. If you keep a pot of sweet basil or Thai basil on the counter, a curious cat chewing a leaf or two is not a poisoning risk. The bigger concern is your plant getting destroyed, or your cat eating so much leaf that they get an upset stomach.

What is in basil?

Basil leaves contain plant compounds called polyphenols, including flavonoids. A basil tincture used as a feed additive was found to contain about 0.187% total polyphenols by weight [3]. That is a processed product, not a fresh leaf, but it shows the compounds of interest are present in small amounts. There is no established nutritional benefit for cats from eating basil. Cats are obligate carnivores and do not need plant matter in their diet.

What About Rosemary Specifically?

Can cats eat rosemary leaves?

Yes, rosemary leaves are non-toxic to cats [2]. A small piece of fresh or dried leaf is safe. Rosemary is woody and needle-like, so it is not the easiest thing for a cat to chew, and most cats will not bother.

Can cats eat rosemary plants?

Yes, the plant is non-toxic [2]. A cat who chews on a rosemary shrub in the yard or a potted plant indoors is not at risk of poisoning from the plant itself.

What is in rosemary?

Rosemary contains antioxidant compounds, mainly carnosic acid and carnosol. These are the compounds measured in commercial rosemary extracts used in pet food [4]. A 2025 study found that rosemary extract reduced ammonia and hydrogen sulfide emissions in cats by 46.84% and 41.64% respectively, which is why it shows up in some odor-control products [5]. Another study found a plant extract blend that included rosemary helped reduce flea populations in cats over five months [6]. These are findings about manufactured products given in controlled amounts, not about sprinkling rosemary on your cat's dinner. Do not expect a pinch of herb to deodorize your cat or repel fleas.

Can Cats Eat Rosemary Extract?

This is where you need to be careful. Rosemary extract is not the same as the leaf.

The European Food Safety Authority reviewed two solvent extracts of rosemary used as feed additives for cats and dogs. The panel concluded that the maximum safe concentration in cat food is 50 mg per kg of feed [4]. That is a tiny amount, calculated by food manufacturers, not something you can measure at home. The same review noted the extracts are skin and eye irritants [4].

Rosemary tinctures, which are water and ethanol solutions, were found safe for target species at a maximum proposed use level of 500 mg per kg of complete feed [7]. Again, this is a manufactured additive at a controlled level.

The practical takeaway: do not add rosemary extract, rosemary oil, or rosemary tincture to your cat's food. Let pet food companies use these ingredients at tested levels. If you want to give your cat rosemary, give a tiny piece of the plain leaf.

Risks of Feeding Rosemary and Basil to Cats

Choking and mouth irritation

Rosemary leaves are stiff and needle-shaped. A cat who swallows a whole sprig may gag or choke. Dried rosemary can be sharp. Chop fresh leaves finely or skip rosemary entirely if your cat eats fast.

Stomach upset

Any plant material can cause vomiting or diarrhea in a cat whose gut is not used to it. A leaf or two is usually fine. A whole handful is likely to come back up.

Essential oils are the real danger

Essential oils are steam-distilled concentrates. A single drop of rosemary or basil oil contains far more plant compounds than a leaf. Cats have limited ability to metabolize many of these compounds, and essential oil exposure can cause drooling, vomiting, wobbliness, tremors, and liver injury. Never apply essential oils to your cat's coat, never diffuse them in a closed room with a cat inside, and never add them to food or water.

Hidden ingredients in human foods

Pesto is the classic trap. Traditional pesto contains basil, garlic, pine nuts, Parmesan, and olive oil. Garlic and onion damage cat red blood cells and can cause anemia. Salt and oil can trigger pancreatitis or digestive upset. A cat who licks pesto off a plate needs a call to your vet, not because of the basil but because of the garlic.

Other risky forms include:

• Herbal teas with added honey or sweeteners
• Seasoning blends that contain onion powder or garlic powder
• Xylitol-sweetened products (xylitol is a dog toxin, but cats should avoid it too)
• Oil-based marinades and dressings

How to Offer Rosemary and Basil Safely

If you want to let your cat try these herbs, keep it simple.

1. Wash the leaf. Rinse under running water to remove pesticides and dirt.
2. Tear or chop a small piece. About a quarter-inch of a leaf is enough for a taste test.
3. Offer it plain. No oil, no salt, no garlic, no dressing.
4. Watch for 24 hours. Note any vomiting, diarrhea, drooling, or behavior change.
5. Keep it occasional. Once or twice a week at most, and only if your cat tolerates it.

Some cats enjoy catnip and other mint-family plants for their scent. If your cat likes herbal smells, Can Cats Eat Catnip? Nepetalactone and Safe Use Guide explains how that plant works. If you are curious about other kitchen herbs, Can Cats Eat Parsley? Furocoumarin Phototoxicity covers a herb that behaves differently from basil and rosemary.

Form-by-form safety table

What If Your Cat Ate Too Much Rosemary or Basil?

If your cat ate a leaf or two off your plant, you probably do not need to do anything. Watch for stomach upset over the next day.

If your cat ate a large amount of the plant, call your veterinarian or a pet poison hotline. Bring the plant or the label with you so the vet knows exactly what was eaten.

If your cat licked or swallowed essential oil, treated themselves from a diffuser, or walked through a spill and groomed it off their paws, treat it as an emergency. Call your vet or an animal poison control service right away. Do not wait for symptoms.

If your cat ate pesto or another garlic-containing food, call your vet. Garlic and onion toxicity can take a day or two to show up as weakness, pale gums, or dark urine.

Safer Alternatives for Herbal Enrichment

If your goal is to give your cat something interesting to sniff or chew, these options are safer and better studied:

• Catnip or silver vine for scent play. See Can Cats Eat Catnip? Nepetalactone and Safe Use Guide.
• Valerian root, which some cats respond to. See Can Cats Eat Valerian Root? Sedative Effect and Dosing.
• A small piece of cooked egg as a treat. See Can Cats Eat Eggs.
• A tiny piece of strawberry for a novel taste. See Can Cats Eat Strawberries? Nutritional Benefits and Risks.

None of these should replace a complete and balanced cat food. Treats, including herbs, should stay under 10% of daily calories.

Limitations and When to Contact a Veterinarian

This article covers general information. Your cat's age, weight, health conditions, and medications change what is safe for them. Individual cases need a veterinarian who can examine your cat and take a full history.

Call your veterinarian the same day if your cat:

• Vomited more than once after eating an herb
• Has diarrhea that lasts more than 12 hours
• Is drooling, pawing at the mouth, or refusing food
• Ate a large amount of plant material

Go to an emergency clinic now if your cat:

• Licked or swallowed essential oil
• Ate pesto, garlic bread, onion-containing food, or a seasoning blend
• Is wobbly, trembling, or having trouble walking
• Has pale gums, fast breathing, or collapse
• Has a swollen face or trouble breathing (possible allergic reaction)

If you are not sure whether the amount eaten was dangerous, call your vet or a pet poison hotline. It is always better to ask than to wait.

Frequently Asked Questions

Can cats eat basil and parsley together?

Basil is non-toxic to cats, but parsley needs more caution because of compounds called furocoumarins that can cause skin reactions in sensitive animals. A tiny piece of basil is fine. If you want to offer parsley, read up on it first and keep the amount very small.

Is dried rosemary safe for cats?

Yes, dried rosemary comes from the same non-toxic plant, so a small pinch is safe. The flavor is more concentrated than fresh, and dried needles are sharp, so crush or grind them before offering. Skip dried rosemary if your cat has a sensitive stomach.

Can I put rosemary oil on my cat for fleas?

No. Essential oils are not safe to apply to cats, and rosemary oil is no exception. Concentrated plant oils can be absorbed through the skin and licked off during grooming, leading to poisoning. Use a flea product prescribed by your veterinarian instead.

Will rosemary or basil hurt my cat's kidneys?

The plain leaves are not known to harm cat kidneys. The concern is concentrated extracts and oils, which can cause liver and other organ injury in cats because they cannot metabolize these compounds well. Keep all essential oils away from your cat.

How much basil can a cat eat?

There is no set safe dose for basil in cats. A small piece of leaf, about a quarter inch, is a reasonable taste test. Anything more risks an upset stomach. If your cat has any health condition, ask your vet before offering herbs.

Related Articles

• Can Cats Eat Eggs
• Can Cats Eat Catnip? Nepetalactone and Safe Use Guide
• Can Cats Eat Valerian Root? Sedative Effect and Dosing
• Can Cats Eat Strawberries? Nutritional Benefits and Risks
• Can Cats Eat Parsley? Furocoumarin Phototoxicity
• Can Cats Safely Eat Tuna

References

1. Toxic and Non-toxic Plants: Basil. ASPCA Animal Poison Control Center.
2. Toxic and Non-toxic Plants: Rosemary. ASPCA Animal Poison Control Center.
3. Safety and efficacy of a feed additive consisting of a tincture derived from the leaves of Ocimum basilicum L. (basil tincture) for use in all animal species (FEFANA asbl). EFSA journal. European Food Safety Authority, 2025.
4. Safety and efficacy of two solvent extracts of rosemary (Rosmarinus officinalis L.) when used as feed additive for cats and dogs (Kemin Nutrisurance Europe SRL). EFSA journal. European Food Safety Authority, 2022.
5. Rosemary Extract Reduces Odor in Cats Through Nitrogen and Sulfur Metabolism by Gut Microbiota-Host Co-Modulation. Animals : an open access journal from MDPI, 2025.
6. A Dietary Plant Extract Formulation Helps Reduce Flea Populations in Cats: A Double-Blind Randomized Study. Pharmaceuticals (Basel, Switzerland), 2023.
7. Safety and efficacy of feed additives consisting of rosemary tinctures obtained from the leaves of Salvia rosmarinus Spenn. for use in all animal species (FEFANA asbl). EFSA journal. European Food Safety Authority, 2025.

Further Reading

• ASPCA Animal Poison Control Center
• ASPCA: People Foods to Avoid Feeding Your Pets
• U.S. Food and Drug Administration: Potentially Dangerous Items for Your Pet