How do you identify cat pee in your house?
It should only be in one place (the litter box) but what if you suspect there is pee somewhere else?
Here is a quick guide to help you to find that pee (so that you can clean it).
SMELL

- Probably the first clue you will have of cat pee in your house will be a nasty smell. It gets worse after a few days, then after a few weeks might seem to go away. But when there is humidity (moisture) in the air, such as on a rainy day, there is is again!
- Fresh cat pee has almost no smell. If there is an underlying medical issue, the urine might smell sweet (could be diabetes) or foul (possible urinary tract infection).
- 3 – 5 day old cat pee smells strongly of ammonia, and depending if it was a tom cat (male, unaltered) it might smell skunky too (testosterone and other hormones affect the smell of urine)
SIGHT
- Do you see an unexpected wet spot on your carpet, floor, bed or clothing? It might be pee.
- Is the color of the wet spot (try blotting with a white paper towel to check color) any shade of yellow? From very light to very dark, even amber…if yes, there is a good chance it is pee.
- If the pee is several days to several weeks old, most of the water will have evaporated and what remains is a very concentrated puddle or splatter of salts, hormones, minerals, sugars, proteins uric acid and urea. It will look very dark in color (often dark yellow to amber). It might even look crystallized, like new ice forming on a pond.
- Depending on what the peed-on surface is, you might even see a bleaching effect (lighter color than usual), especially with dark fabrics.
FEEL
- If you step in a warm and wet puddle, the pee is very fresh – likely within 30 minutes
- If you touch something that feels sticky on your fingertips, that is likely almost dried and highly concentrated cat urine
- Did you find an area that looks like crystallized orange or deep yellow “something”? That could be very old cat pee (several months or years). Usually this will be found in slightly recessed area that could hold a puddle of cat pee for a long time until all the water evaporated.
HEARING
- Yes, sometimes you will hear a cat peeing in the house. You might hear the sound of a running tap or rushing water (in a place where there usually isn’t water in your house). Or you might hear your cat scratching/pawing at the carpet or ground or soft covering (ex. bathroom rug, bed sheets) as they try to cover up their urine.
OTHER CLUES
- Other clues might include watching the behavior of your other pets (dogs, or other cats in the house). If you find them sniffing intently at an area that normally would not be that exciting to smell (ex wall, corner of bed), that is a clue that there is something they can smell but you can’t (yet).
- Use a black light when it is completely dark and scan the area – floors and all vertical surfaces up to 24 inches off the ground. Black light will make urine glow green/yellow. Circular spots on the floor indicate “inappropriate urination”. Splatter areas against vertical surfaces indicate “spraying”. It is important to know which of these two your cat is doing. This will help the veterinarian to determine what might be the problem.