# Why Do Cats Groom Each Other? Allogrooming Explained Yes, it is normal for cats to groom each other. Social grooming, called allogrooming, is a friendly behavior that helps cats bond, share scent, and keep peace in a group. It becomes a concern when one cat grooms a housemate so much that fur thins, skin reddens, or the other cat cannot get away. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - Allogrooming is normal and usually a sign that two cats have a friendly, relaxed relationship. - Cats regulate their social life through friendly contact like grooming, rubbing, and nose touching, along with distance and occasional conflict [1]. - Grooming another cat's private areas is common and usually normal, especially between cats that are closely bonded. - Watch the receiver. If the groomed cat stays relaxed, it is fine. If it flinches, hisses, or leaves, the grooming has crossed a line. - Sudden, intense, or one-sided grooming that causes hair loss or skin damage needs a veterinary visit. ## Why Do Cats Groom Each Other? Grooming is a big part of a cat's day. Cats sleep about 40% of the day, rest about 22%, and groom about 15% [1]. Most of that grooming is self-grooming, but cats also groom each other when they live together. ### Allogrooming is a bonding behavior Cats are often described as solitary, but that is not the whole picture. Many cats are quite social in the right circumstances, and outdoor cats form stable groups when there is enough food [2]. Within those groups, cats use friendly behaviors to keep the peace. Rubbing, grooming, and nose touching are all affiliative displays, meaning they signal friendship instead of conflict [1]. Allogrooming does several jobs at once. It spreads a shared scent through the group, which helps cats recognize each other as familiar. It reinforces social bonds. It also lets one cat test whether another cat is relaxed enough to allow close contact. ### Grooming is not constant, even between friends Cats with better relationships spend more time closer together than cats with poor relationships, but even friendly cats spend most of their time apart [1]. In one study of cats living in a cat café, cat-to-cat interactions were infrequent, about 0.58 interactions per cat per hour, and just over half were friendly [3]. Avoidance, not fighting, is the main way cats reduce conflict [3]. That matters for how you read allogrooming. A pair of cats that groom each other now and then, then go sleep in separate spots, is behaving normally. Constant clinging and grooming is not the cat version of a healthy friendship. ### Why cats groom each other's private areas Owners often ask whether it is normal for cats to clean each other's privates. Yes, it usually is. Cats cannot easily reach some parts of their own body, and the rear end and genital area are prime targets for a grooming partner. This is most common between cats that are closely bonded, often littermates or cats that grew up together. The key question is not where the grooming happens. It is how both cats respond. If the cat being groomed lies still, purrs, or leans in, the behavior is mutual and relaxed. If it squirms, growls, or walks away and the other cat follows, that is not grooming anymore. That is harassment. ### Grooming can also be a displacement behavior Sometimes allogrooming shows up when a cat is mildly uneasy. A cat that is not sure how to respond to another cat may start grooming it, the same way some cats groom themselves when they are stressed. This is not always a problem, but a sudden increase in grooming directed at one housemate is worth watching. ## Medical Causes to Rule Out Before you treat allogrooming as a behavior problem, rule out physical causes. Skin disease and itch can change grooming in both the cat doing the grooming and the cat being groomed. ### Itch and skin disease in the groomed cat If one cat suddenly starts over-grooming a housemate, the housemate may be itchy. Fleas, allergies, and skin infections all cause itch, and a bonded cat may focus on the same spot the itchy cat has been chewing. If you see scratching, redness, scabs, or hair loss on the cat being groomed, start with a veterinary exam. See [Why Is My Cat So Itchy?](/knowledge/veterinary-medicine/parasitic-diseases/why-is-my-cat-so-itchy) for common causes. ### Over-grooming in the cat doing the grooming The groomer can have a problem too. Grooming is a maintenance behavior, and it changes with itch and with some psychological conditions [4]. Cats with psychogenic alopecia, a stress-related hair loss condition, groom differently from healthy cats. In one study, cats with this condition groomed fewer body parts per bout than healthy shorthair cats [4]. Hairless cats also chewed their skin longer than other cats [4]. If the cat doing the grooming is losing hair, developing bald patches, or licking itself raw, that is a medical issue, not a personality quirk. Read [Why Is My Cat Grooming So Much?](/knowledge/veterinary-medicine/parasitic-diseases/why-is-my-cat-grooming-so-much) and [Why Is My Cat pulling out fur in clumps? Psychogenic Alopecia and Over-Grooming](/knowledge/veterinary-medicine/symptom-guides/why-is-my-cat-pulling-out-fur-in-clumps-psychogenic-alopecia-and-over-grooming). ### Pain and mobility problems A cat in pain may groom the sore area more, or may stop grooming altogether. Arthritis, dental pain, and abdominal discomfort can all change grooming habits. Any sudden change in grooming, in either direction, deserves a veterinary look. ## Is It Normal for Cats to Groom Each Other All the Time? Occasional allogrooming is normal. Constant, focused, one-sided grooming is not. ### Signs the grooming is still healthy - Both cats stay loose and relaxed. - The cat being groomed can walk away without being followed. - Grooming happens in short bouts, not marathon sessions. - Both cats groom each other at least some of the time. - No hair loss, redness, scabs, or bald spots on either cat. ### Signs the grooming has become a problem - One cat does almost all the grooming. - The groomed cat flinches, twitches its tail, hisses, or tries to leave. - The groomer pins or blocks the other cat to keep grooming. - Fur is thinning or missing on the groomed cat, often on the neck, back, or shoulders. - The skin underneath looks red, irritated, or broken. - The behavior started suddenly after a change at home, such as a new pet, a move, or a new schedule. Conflict between cats is common in multi-cat homes. In a survey of owners with two to four cats, 73.3% reported conflict signs from the very beginning when the cats were introduced, and conflict signs got more frequent as the number of cats in the home went up [5]. Staring was the most common conflict sign, reported at least daily in 44.9% of households, followed by chasing, stalking, fleeing, tail twitching, hissing, and wailing [5]. Over-grooming often travels with that kind of tension. If your cats are staring, blocking, or chasing each other, the grooming may be part of a bigger social problem. ## What to Do Step by Step ### Step 1: Get a veterinary exam first Book a visit for both cats if you can. Your veterinarian will check for fleas, skin infections, allergies, and pain. They will also assess the groomer for stress-related over-grooming. Treatment depends on the diagnosis, and your veterinarian will calculate any medication dose based on your cat's weight and health. ### Step 2: Add more resources Most cat tension comes down to competition for space, food, litter boxes, and resting spots. Spread resources out so no cat has to pass another cat to reach them. - One litter box per cat, plus one extra, in separate locations. - Food and water stations in more than one room. - Multiple scratching posts and perches. - Beds and hiding spots at different heights. Elevated structures matter. In a study of cats in a cat café, cats used vertical levels and cat-only rooms more during busy periods [3]. Height gives a cat a way to opt out of social contact without a fight. ### Step 3: Give the groomed cat an escape route If one cat is being over-groomed, make sure it can leave. Add a cat door, a baby gate with a gap, or a tall perch the other cat cannot easily reach. A cat that can retreat will often do so before tension turns into a fight. ### Step 4: Break the cycle with calm, brief interruptions When grooming starts to look one-sided, distract both cats with a toy, a treat toss, or a call to a different room. Do not yell or spray water. You want to interrupt the pattern without adding stress. ### Step 5: Build positive associations Feed the cats on opposite sides of a door or at a distance where both stay relaxed. Pair the presence of the other cat with food, play, and calm attention. This is the same approach used for slow introductions, and it works for repairing strained relationships too. ### Step 6: Keep a simple log Note when the grooming happens, how long it lasts, which cat starts it, and how the other cat responds. Bring the log to your veterinarian. Patterns are much easier to spot on paper than in memory. ### Step 7: Support the bond with humans too Your relationship with each cat matters. In a study of owner-cat interactions, passive interactions were linked to higher oxytocin and lower cortisol in cats, while forced interactions showed the opposite pattern [6]. Secure cats had more positive hormonal responses to human contact than insecure cats [6]. In plain terms, let your cats come to you. Petting a cat that is trying to leave does not help anyone. ## What Not to Do ### Do not punish either cat Punishment adds stress to an already tense household. It can also teach the groomed cat to hide signs of discomfort, which makes the problem harder to see. Never use spray bottles, loud noises, or physical correction. ### Do not assume it is always affection Allogrooming is often friendly, but it can also be a stress behavior. If one cat is losing fur or the other cat is trapped, do not write it off as love. ### Do not separate cats permanently without a plan Some cats do need to live apart, but that is a last resort. Sudden isolation can cause its own stress. Work with your veterinarian or a behavior professional before you make a permanent change. ### Do not rely on myths Cats are not solitary by nature, and they are not all loners. Many cats get along well in groups, and friendly contact like grooming is part of how they do it [2]. At the same time, a cat that wants space is not being dramatic. Respect both cats. ### Do not skip the skin check If the groomed cat has bald patches, scabs, or red skin, that is a medical sign. Do not wait to see if it resolves on its own. ## When to Involve a Veterinarian or Behavior Professional Call your veterinarian if grooming causes hair loss, skin redness, or scabs on either cat. Call if one cat is losing weight, hiding, or avoiding the litter box. Call if the grooming is one-sided and the other cat cannot escape. Ask for a referral to a veterinary behaviorist or a certified behavior professional if: - The behavior continues after medical causes are treated. - Fights, chasing, or blocking happen daily. - One cat is hiding most of the day. - You have tried environmental changes and the tension is not improving. - You are considering rehoming one of the cats. A certified behavior professional can assess the household, watch how the cats interact, and build a plan that fits your home. ## Limitations and When to Contact a Veterinarian This article covers general patterns. Every cat is an individual, and individual cases need a veterinarian who can examine your cats and review their history. Contact your veterinarian the same day if: - One cat has a raw, bleeding, or infected-looking patch of skin. - The groomed cat is crying, hiding, or refusing food. - You see limping, swelling, or a wound. - The grooming started suddenly and is intense. Go to an emergency clinic now if: - A fight caused a deep bite, heavy bleeding, or a wound on the chest or belly. - A cat is struggling to breathe, collapsed, or unresponsive. - You suspect a toxin exposure. Call poison control right away. The ASPCA Animal Poison Control Center is (888) 426-4435 and the Pet Poison Helpline is (855) 764-7661. Schedule a routine visit if: - Grooming habits changed gradually over weeks. - One cat has mild hair thinning but seems otherwise well. - You want help with a slow introduction or a tense multi-cat home. ## Frequently Asked Questions ### Is it normal for cats to clean each other? Yes, it is normal. Social grooming is a friendly behavior that helps cats bond and share scent, and it is common between cats that live together and get along. The behavior is only a concern when it becomes one-sided, constant, or damaging to the skin and coat. ### Why does one cat groom the other but not get groomed back? Grooming is not always a fair trade. One cat may be more outgoing or more anxious, and it may do most of the grooming. If the other cat stays relaxed and can leave when it wants, this is usually fine. If the groomed cat is trapped, tense, or losing fur, treat it as a problem. ### Can stress cause a cat to over-groom its housemate? Yes. Grooming behavior changes with psychological conditions in cats, and stress in the home can shift how much one cat grooms another. A new pet, a move, or a change in routine often triggers it. If the behavior starts after a household change, that timing is a strong clue. ### Should I stop my cats from grooming each other? Usually no. Let normal, mutual grooming continue. Interrupt only when the grooming is one-sided, lasts too long, or makes one cat uncomfortable. A calm distraction works better than punishment. ### Do cats that groom each other always get along? No. Grooming is a friendly signal, but it does not guarantee a strong bond. Cats can groom a housemate they are unsure about, and tension can still exist in the home. Watch for staring, chasing, and blocking, which are common conflict signs in multi-cat households [5]. ## Related Articles - [Why Is My Cat Grooming So Much?](/knowledge/veterinary-medicine/parasitic-diseases/why-is-my-cat-grooming-so-much) - [Why Is My Cat pulling out fur in clumps? Psychogenic Alopecia and Over-Grooming](/knowledge/veterinary-medicine/symptom-guides/why-is-my-cat-pulling-out-fur-in-clumps-psychogenic-alopecia-and-over-grooming) - [Why Is My Cat So Itchy?](/knowledge/veterinary-medicine/parasitic-diseases/why-is-my-cat-so-itchy) - [Why Is My Cat Peeing on the Floor Right in Front of Me?](/knowledge/veterinary-medicine/anxiety-and-behavior-support/cat-peeing-in-front-of-me) - [Why Is My Cat Peeing on the Rug? Medical and Behavioral Reasons](/knowledge/veterinary-medicine/anxiety-and-behavior-support/cat-peeing-on-rug) - [Why Is My Cat Losing Hair?](/knowledge/veterinary-medicine/parasitic-diseases/why-is-my-cat-losing-hair) - [Why Is My Cat Grooming Another Cat?](/knowledge/veterinary-medicine/behavior/cat-grooming-other-cat) - [Is It Normal for Cats to Lick Themselves a Lot?](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/cat-licking-itself-excessively) - [Cat Not Grooming: Why It Happens and What to Do](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/cat-not-grooming-itself) ## References 1. [Social Behavior of Cats - Behavior](https://www.merckvetmanual.com/behavior/behavior-of-cats/social-behavior-of-cats). Merck Veterinary Manual. 2. [Normal Social Behavior in Cats - Cat Owners](https://www.merckvetmanual.com/cat-owners/behavior-of-cats/normal-social-behavior-in-cats). Merck Veterinary Manual. 3. [Cats in a Cat Café: Individual Cat Behavior and Interactions with Humans](https://pubmed.ncbi.nlm.nih.gov/41301942/). Animals : an open access journal from MDPI, 2025. 4. [Exploring Normal to Abnormal Variations of Grooming Behaviours in Cats](https://pubmed.ncbi.nlm.nih.gov/42504124/). Veterinary dermatology, 2026. 5. [Conflict and affiliative behavior frequency between cats in multi-cat households: a survey-based study](https://pubmed.ncbi.nlm.nih.gov/31623526/). Journal of feline medicine and surgery, 2020. 6. [EXPRESS: The hormonal effects of owner-cat interactions on pet cats of different potential attachment styles](https://pubmed.ncbi.nlm.nih.gov/42557850/). Journal of feline medicine and surgery, 2026. ## Further Reading - [Merck Veterinary Manual: Cat Owners](https://www.merckvetmanual.com/cat-owners) - [Cornell Feline Health Center: Health Information](https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information) - [American Veterinary Medical Association: Pet Care](https://www.avma.org/resources-tools/pet-owners/petcare)