When a cat closes its eyes around you, it’s usually a sign of trust and relaxation. Cats are hardwired to stay alert, so voluntarily shutting their eyes in your presence signals they feel safe. But context matters. A slow, deliberate blink means something very different from a cat that’s squinting with one eye or keeping both eyes tightly shut. Here’s how to tell what your cat is communicating.
The Slow Blink: A Cat’s Way of Saying “I Trust You”
The most well-known version of eye closing in cats is the slow blink, sometimes called a “cat kiss.” Your cat looks at you, narrows its eyes, holds them partially or fully closed for a moment, then opens them again. This isn’t random. A 2020 study published in Scientific Reports tested what happens when humans slow-blink at their cats versus simply sitting nearby without interacting. Cats responded with significantly more half-blinks and eye narrowing when their owners slow-blinked at them first.
The same study ran a second experiment with a stranger instead of the owner. Cats were more likely to approach the unfamiliar person after receiving a slow blink than when the person maintained a neutral expression. This held true across cats of different ages and sexes, suggesting the slow blink functions as a genuine form of positive emotional communication, not just a response to a familiar face.
You can try this yourself. Look at your cat softly, narrow your eyes, and close them slowly for a second or two before opening them again. Many cats will mirror the gesture back. It’s one of the simplest ways to build rapport with a cat, especially one that’s shy or new to your home.
Resting With Eyes Closed or Half-Closed
Cats sleep 12 to 16 hours a day, and much of that time is spent in a light, semi-alert doze rather than deep sleep. During these catnaps, a cat’s eyes may be mostly closed but not fully shut. You might notice the lids fluttering or the ears still rotating toward sounds. This mirrors the sleeping habits of wild cats, who need to stay alert to potential threats even while resting.
During deeper sleep, cats enter a REM stage similar to ours. Their eyes move rapidly behind closed lids, and you may see twitching in their ears, whiskers, paws, and tail as they dream. If your cat is curled up, fully relaxed, and its eyes are closed with occasional twitching, it’s simply in a deep sleep cycle. There’s nothing to worry about.
Squinting as a Sign of Pain
Not all eye closing is comfortable. Cats are notoriously good at hiding pain, but their faces give them away. Veterinary researchers developed a tool called the Feline Grimace Scale that scores five facial features to detect pain in cats: ear position, eye tightening, muzzle tension, whisker position, and head posture. Orbital tightening, where a cat squints or partially closes its eyes, is one of the most reliable indicators.
A cat in pain will often squint with both eyes in a way that looks different from a relaxed blink. The eyelids appear tense rather than soft, and you’ll typically see other signs at the same time: ears flattened or rotated outward, whiskers pulled tight against the face, or the head held lower than usual. If your cat’s squinting comes with changes in behavior like hiding, refusing food, or resisting being touched, pain is a likely cause.
Eye Problems That Cause Closing or Squinting
When a cat holds one eye closed or squints persistently, an eye condition is often responsible. Conjunctivitis is the most frequently diagnosed eye disorder in cats. It’s an inflammation of the membrane lining the eyelid and eyeball surface, typically caused by an upper respiratory infection (bacterial or viral). Signs include squinting, frequent blinking, and discharge that ranges from clear and watery to thick and dark-colored.
Uveitis, an inflammation inside the eye itself, causes squinting along with swollen third eyelids and visibly enlarged eyes. Cats are also about six times more sensitive to light than humans, thanks to a reflective layer behind the retina called the tapetum lucidum. This means any eye inflammation that wouldn’t bother a human much can make a cat intensely light-sensitive, causing them to keep the affected eye shut, especially in bright rooms.
You might also notice a thin white or pinkish membrane creeping across your cat’s eye from the inner corner. That’s the third eyelid, which is normally tucked out of sight. When it becomes visible in both eyes, it can indicate a condition called Haws syndrome, which is frequently linked to gastrointestinal inflammation. Affected cats often have watery diarrhea that started before the eye changes appeared.
How to Tell Comfort From Concern
A healthy cat’s eyes are bright, clear, and equal in pupil size. They don’t squint with either eye. The simplest way to distinguish a contented eye-close from a medical one is to look at the full picture:
- Relaxed closing: Both eyes narrow softly, the body is loose, and the behavior is intermittent. Your cat may purr or knead at the same time. This is trust or sleepiness.
- Painful squinting: One or both eyes stay tightened, the face looks tense, and the cat’s overall posture is stiff or withdrawn. Ears and whiskers shift position.
- Infection or injury: One eye stays mostly shut or produces discharge. You may see redness, swelling, or cloudiness in the affected eye.
Signs That Need Prompt Attention
Some eye symptoms require a veterinary visit within 24 hours or sooner. Watch for cloudiness or a bluish haze over the eye, uneven pupil sizes, visible blood inside the eye, a bulging or sunken appearance, or thick colored discharge. A cat that’s pawing at its face repeatedly or suddenly hiding is also signaling something more serious than sleepiness. Eye conditions in cats can deteriorate quickly, and early treatment often determines whether vision is preserved.