Why does my cat's tail puff up?
A puffed-up, bottle-brush tail means the fur is standing on end. Your cat is highly aroused: usually startled or frightened, sometimes just very excited.
What it usually means
Pawfect's cat tables call this piloerection: fur along the spine or tail fluffing out to make the cat look bigger. They read it as high arousal that could be fear, upset or intense excitement, depending on the context and the other signals.
With an arched back, a hiss or ears pinned flat it is part of a defensive display, and the best help is distance and a quiet way out. In a kitten racing round the hallway with loose, bouncy movements, it is more likely over-the-top play.
Easy to mix up
- A naturally fluffy tail. Long-haired cats look fluffy all the time; the tables look for a sudden change.
- A friendly upright tail. A tail held straight up with smooth fur is a hello, not alarm.
Look at the whole body
No single signal tells the whole story. Before settling on a reading, look at the tail, ears, eyes, mouth and posture together, and at what is happening around your pet.
Signals the tables often see alongside this one
- Arched back
- Hiss
- Ears pinned flat
See it on your own pet
Point Pawfect at your dog or cat and it picks out the tails, ears, eyes and postures from these guides, then plays them back as a playful caption you can keep.
Related guides
Why does my cat arch its back?
An arched back can mean play or fear. How the sideways play hop differs from a defensive arch, and what to look at.What does it mean when my cat holds its tail straight up?
A tail held high, sometimes with a little hook at the tip, is a friendly hello. What it usually means, and what a quivering tail adds.Why do my dog's hackles go up?
Raised fur along the back means high arousal: fear, excitement or tension. How to tell which from the rest of the body.
Where this comes from
Built on the body-language tables behind Pawfect's analysis (dogs v2.1.0, cats v1.0.1), which draw on published work including:
- John Bradshaw, Cat Sense: How the New Feline Science Can Make You a Better Friend to Your Pet (2013)
- Dennis C. Turner and Patrick Bateson (eds.), The Domestic Cat: The Biology of its Behaviour (3rd edition) (2014)
- Karen L. Overall, Clinical Behavioral Medicine for Small Animals (1997)
- Sarah L. Ellis et al., Feline communication and body language (2013)
- International Cat Care, Online resources on feline behavior and body language (2023)