Why Is My Cat Losing Hair? Causes of Cat Hair Loss

Finding clumps of cat fur around the house is one thing — but actual bald patches on your cat are a different matter entirely. Hair loss in cats (alopecia) is almost always a sign that something needs attention.

Normal Shedding vs. Abnormal Hair Loss

All cats shed — but normal shedding doesn’t produce bald patches. Abnormal hair loss creates visible thinning, bare skin, or irregular patches. If you can see skin through the fur, that’s alopecia — not shedding.

Over-Grooming (Psychogenic Alopecia)

The most common cause of symmetrical hair loss — particularly on the belly, inner thighs, and flanks — is over-grooming driven by stress or anxiety. Typical triggers: a new pet, house move, change in routine, or separation anxiety. The hair loss is typically very symmetrical and the skin underneath looks normal.

Allergies

Environmental and food allergies cause intense itching which leads to over-grooming and hair loss. Food allergies are particularly associated with hair loss around the head and neck.

Ringworm

Despite the name, ringworm is a fungal infection. It causes circular or irregular patches of hair loss, often with a scaly, crusty edge. It’s contagious to other cats, dogs, and humans.

Parasites

Fleas cause intense itching and over-grooming, particularly around the base of the tail. Even one flea bite can cause severe reaction in a flea-allergic cat.

Hormonal Causes

Hyperthyroidism and Cushing’s disease can cause symmetrical hair thinning, usually accompanied by other signs — weight changes, altered thirst, behaviour changes.

Hair loss in cats always has a cause — and once identified, it’s almost always treatable with the coat growing back fully.