Cats are normally very particular about where they urinate, so urinating indoors in an inappropriate place is often a sign of trouble from your cat. While it's not always medical, you should still take this inappropriate urination as a sign from your feline friend.
Take your cat to the vet, particularly if she has started inappropriately urinating "all of a sudden." Your vet may be able to determine if there are any medical issues prompting the cat to urinate in new and unusual places.
Keep the litter box clean and in the same location. If you must move the litter box, keep one litter box in the old location while your cat gets used to having a litter box in the new location.
Switch the litter to a lower dust, unscented formula. Dust and scent can deter a cat from using the litter box.
Scoop your litter boxes at least daily, although scooping the litter box as frequently as it's used is preferable.
Wash the litter box weekly to remove the odors from the box. Plastic is particularly capable of holding odors, which over time may deter the cat from using the box.
Clean the area where the cat has urinated thoroughly. Because cats are so particular about where they urinate, once they have urinated in an area they will continue to use it. Use an enzyme-powered cleaning agent to completely remove the odor, as the cat will use the odor as a signal to urinate in that spot more.
Allow your cat access to the outdoors if she has always urinated outside. Installing a flap-door is one such way to allow this access.
Place discreet, large litter boxes inside, particularly if your cat is used to relieving herself outside. Older cats or those with medical problems may not always be able to get outside when the time comes to relieve themselves.
Keep other cats out of your yard by chasing them away or installing deterrents. Both male and female cats, whether fixed or not, may spray their territory to protect it against rivals.
Install at least one litter box per cat in your home. Even if you have had multiple cats for a long time, they may start urinating out of frustration suddenly.
With a professional background in gardening, landscapes, pests and natural ecosystems, Jasey Kelly has been sharing her knowledge through writing since 2009 and has served as an expert writer in these fields. Kelly's background also includes childcare, and animal rescue and care.