Why is my cat losing hair?
Hair loss in cats has several common causes — over-grooming from stress or itchiness, fleas, allergies, ringworm and other skin infections all being frequent culprits — and telling them apart reliably needs a vet to examine your cat directly rather than guessing from the pattern of hair loss alone. It is common enough not to panic over, but it is also not something to leave unchecked, since some causes are contagious to other pets or spread if left untreated.
Usually not urgent
This is common and often manageable at home — but see a vet if it persists, gets worse, or comes with other changes.
Over-grooming and stress
Cats who are stressed, anxious, or in mild discomfort somewhere on their body sometimes over-groom a specific area repeatedly, which can wear away fur without an obvious skin problem underneath. This is sometimes linked to environmental stress — a new pet, a house move, changes at home — though it can also be a response to a genuine underlying itch or pain that needs identifying rather than assumed to be behavioural.
Because over-grooming can be both a cause and a symptom of something else going on, it is worth having it checked rather than assuming it is purely behavioural, particularly if it is focused on one area or is getting worse.
This kind of hair loss often has a fairly distinctive pattern — commonly along the belly, inner legs, or lower back, in a fairly symmetrical shape on both sides of the body — because it comes from a cat's own tongue rather than a patch of skin failing on its own. Spotting a cat mid-groom, rather than only noticing the hair loss afterward, can be a useful clue if you are trying to describe the pattern to your vet.
Fleas, allergies and skin infections
Fleas are one of the most common causes of hair loss and itching in cats, and even a cat who does not go outdoors can pick them up from other pets or a home environment. Regular flea prevention, as advised by your vet, rules this out as a straightforward first step.
Ringworm, despite the name, is a fungal skin infection rather than a worm, and it can cause patchy hair loss that is contagious to other pets and to people, which makes a proper diagnosis important rather than optional. Food or environmental allergies can also cause hair loss, usually alongside itching, and these typically need investigation over time to identify the trigger.
What to look at and note
Note where the hair loss is — one focused patch, symmetrical patterns on both sides, or widespread thinning all point a vet in different directions. Check for redness, scabs, flaking, or visible parasites, and note whether your cat seems itchy, is over-grooming visibly, or seems otherwise their normal self.
How quickly it appeared and whether it is spreading are also useful details to have ready, along with whether any other pets in the household are showing similar signs, which matters especially if a contagious cause like ringworm is a possibility.
It is also worth thinking back over anything that changed recently — a new food, a new flea treatment, a stressful event at home, or a new pet — since this kind of timeline can point a vet towards an allergy or a stress trigger faster than the hair loss pattern alone.
When to see a vet
See your vet if the hair loss is spreading, if there is redness, scabbing or visible skin damage, if your cat seems uncomfortable or is over-grooming heavily, or if other pets in the household develop similar patches, since this can suggest a contagious cause. A vet can examine the skin, check for parasites, and run tests where needed to identify the actual cause rather than guessing.
Diagnosis sometimes takes a process of elimination — ruling out parasites and infection first, then looking at diet and environment for an allergy — rather than a single test giving an instant answer, so do not be surprised if your vet suggests a step-by-step approach rather than an immediate diagnosis on the first visit.
This is general information, not veterinary advice, and it cannot replace an examination by the vet who knows your cat. Persistent or worsening hair loss is always worth having looked at properly.
What can help
Things we stock that owners commonly use alongside a vet’s advice — not a substitute for it.
Wahl Pet Grooming Scissors with Finger Rest
Stainless steel finishing scissors with ergonomic offset handles — perfect for tidying around eyes, ears, mouth, and paws.
£5.49
Groom Professional Curved Soft Slicker Brush
A professional-grade curved slicker brush with soft pins, designed to groom delicate and soft-coated pets without discomfort.
From£8.99
Wolseley A2 Clipper Blade — 78mm Width
A reliable professional clipper blade offering a 2–3mm depth of cut, well suited to routine winter clipping work.
£6.49
Pet Head Hair Mist Peony & Cashmere
Pet Head Hair Mist Peony & Cashmere is listed in our dog clothing range for pets. The page brings together the available option labels and the product facts that can be checked, so unsupported claims are left out.
£8.99
Common questions
- Can stress cause hair loss in cats?
- Yes, stress-related over-grooming is a recognised cause of hair loss in cats, often focused on one area such as the belly or legs. It is worth having checked by a vet even so, since over-grooming can also be a response to an underlying itch or discomfort that needs identifying.
- Is cat hair loss always caused by fleas?
- No, though fleas are one of the most common causes. Allergies, ringworm, stress-related over-grooming and other skin conditions can all cause hair loss too, and a vet examination is the reliable way to tell them apart.
- Is ringworm in cats dangerous to humans?
- Ringworm is a fungal infection that can spread between pets and to people, so it is worth taking seriously and having properly diagnosed and treated rather than assumed to be something else. Basic hygiene, like washing hands after handling an affected cat, is sensible while it is confirmed and treated.
- Should I be worried if my cat is losing hair in one patch?
- A single, well-defined patch is worth having checked rather than ignored, since it can point to causes ranging from ringworm to a localised skin irritation. It is not usually an emergency, but persistent or spreading patches should see a vet.
Related
Sources
Written against guidance published by UK veterinary and welfare organisations. Always confirm specifics with your own vet.
Written by Matt Garnett, who runs Giddy Pets and is a lifelong pet owner — not a vet. This is general information, not veterinary advice, and it cannot replace an examination by the vet who knows your animal. How we write these guides.