Cats are remarkably good at hiding pain. Their evolutionary history as solitary hunters gave them a strong instinct to mask vulnerability, since showing weakness in the wild attracts predators. This means your cat can be dealing with significant discomfort, even chronic conditions like arthritis, without ever crying out or limping obviously. Roughly 60% of cats over age six have degenerative joint disease, yet in one study, only 1% were identified through standard veterinary records alone, a gap that reveals just how effective cats are at concealing what they feel.
Why Cats Evolved to Hide Pain
Dogs are social animals that benefit from signaling distress to their pack. Cats, by contrast, evolved as solitary hunters. A limping or visibly weakened cat in the wild becomes a target for larger predators rather than a candidate for group care. Over thousands of generations, this pressure selected for cats that could suppress outward signs of injury or illness and carry on as normally as possible. That instinct didn’t disappear with domestication. Your housecat still runs the same internal program: conceal vulnerability first, deal with it later.
Behavioral Signs That Suggest Pain
Because cats won’t tell you something hurts, you have to watch for shifts in their normal routines. These changes are often subtle and easy to dismiss as aging or moodiness, but they can be the only clues you get.
Changes in Jumping and Movement
One of the earliest and most common indicators of pain, especially joint pain, is a change in how your cat moves vertically. A cat that once leaped onto the kitchen counter in a single motion may start using a chair as an intermediate step, or stop jumping altogether. You might notice hesitation before a jump, a lower arc, or an awkward landing. Stiff gait, particularly after resting, is another hallmark. These signs are so reliably linked to joint disease that improvement in jumping willingness and jump height are used as benchmarks when evaluating whether pain treatment is working.
Grooming Changes
Cats are meticulous groomers, so any disruption to that routine is worth paying attention to. A cat in pain may stop grooming areas that are hard to reach, leading to a matted, greasy, or unkempt coat along the back, belly, or hindquarters. On the other hand, some cats over-groom a painful area, licking it obsessively until the fur thins or the skin becomes irritated. Both patterns signal that something is off.
Social Withdrawal or Aggression
A previously friendly cat that starts hiding, avoiding contact, or spending more time alone may be in pain. Withdrawal is a natural extension of the instinct to mask vulnerability. Some cats go the opposite direction and become aggressive, swatting or biting when touched in ways they previously enjoyed. Cats with arthritis or dental disease commonly become defensive during handling, and their overall mood can shift noticeably. Research on cats with bladder inflammation has even linked the condition to increased general anxiety, which may itself be driven by ongoing pain.
Litter Box Problems
When a previously reliable cat starts having accidents outside the litter box, pain is one of the first things to consider. Cats with sore joints may struggle to climb into a box with high sides, or they may not make it to the box in time if it’s far away or up a flight of stairs. Cornell University’s veterinary program specifically recommends low-sided boxes for cats with joint pain or mobility problems. If your cat suddenly stops using the litter box, that’s worth investigating as a pain signal rather than a behavioral issue.
Facial Expressions You Can Learn to Read
Researchers developed the Feline Grimace Scale to help identify pain by looking at a cat’s face. It focuses on five specific features: ear position, the tightness of the area around the eyes, tension in the muzzle, whisker position, and head position. Each feature is scored on a scale from absent to markedly present.
In practice, a cat in pain tends to flatten or rotate its ears outward, squint or tighten the muscles around its eyes, and tense its muzzle so the normal rounded shape becomes more compressed. The whiskers may fan out or push forward, and the head drops below the shoulder line. None of these signs are dramatic on their own, but when several appear together, they’re a reliable indicator. You can find the scale’s reference images online to compare against your own cat’s expressions.
Purring Does Not Mean Comfort
One of the most misleading signals is purring. Most people associate it with a content, relaxed cat, and it usually is exactly that. But cats also purr when they’re in pain, stressed, or frightened. It functions as a self-soothing mechanism, similar to how a person might rock back and forth during distress. If your cat is purring at a time when you wouldn’t normally expect it, particularly while also showing other behavioral changes, the purring itself may be a sign that something is wrong rather than evidence that everything is fine.
Why Standard Vet Visits Often Miss It
Even veterinarians can struggle to detect pain in cats. Physiological markers like heart rate, respiratory rate, and pupil size don’t correlate well with pain in this species. Stress, fear, and the anxiety of being in a clinic can spike all those same readings, making them unreliable. Blood pressure is the one physiological marker that has shown some correlation with pain levels, but it’s not always practical to measure in a busy clinic setting.
The bigger issue is that cats often suppress their pain signals even more intensely in an unfamiliar environment. A cat with significant arthritis at home may move carefully around the exam room without showing obvious lameness, because the stress of being at the vet activates that same instinct to appear normal. This is why your observations at home are so valuable. When one study used a structured checklist that asked owners about specific daily activities, 39% of cats showed at least one sign consistent with joint pain. Among cats over 12, that number jumped to 71%. Without the checklist, the retrospective detection rate was just 1%.
What to Watch for at Home
The most useful thing you can do is establish a baseline of your cat’s normal behavior, then notice when it shifts. Pay attention to how high and how often your cat jumps, where they choose to sleep, how they interact with family members, how well they groom themselves, and how reliably they use the litter box. Changes in any of these areas, even gradual ones, can indicate pain that your cat is working hard to hide.
Keep in mind that cats tend to change slowly. A cat with developing arthritis doesn’t suddenly stop jumping. It stops jumping onto the highest surfaces first, then gradually lowers its range over weeks or months. If you only notice the end stage, where the cat has stopped jumping entirely, you may have missed months of treatable discomfort. Periodic video of your cat moving around your home can help you spot trends that are hard to catch day to day, and it gives your vet something concrete to review.