How to Remove Cat Urine Odor and Stains From Carpet and Floors

By Tailwisp Editorial TeamUpdated October 20, 20264 min read

Few household smells are as stubborn as cat urine. Even after cleaning, a faint odor can linger, drawing the cat back to the same spot. Understanding why helps you remove it properly and prevent repeat accidents.

Why it lingers

Fresh urine is mostly water and urea. Bacteria convert urea to ammonia, which creates the sharp smell. Uric acid crystals, left behind as urine dries, are insoluble and can reactivate in humid weather. Ordinary soap and water remove the visible stain but not the crystals. Enzymatic cleaners contain bacteria or enzymes that break down these compounds.

First, see the vet if needed

Urine accidents can be a medical sign. See your vet if your cat:

• Strains, cries or goes in and out of the litter box. See signs of a urinary blockage in cats.
• Passes blood
• Urinates more often or in large amounts
• Has a sudden change in habits

A blocked male cat is an emergency. See the emergency warning signs guide, and use the US vet directory to find a clinic. See also why is my cat peeing outside the litter box.

What you need

• Paper towels or old cloths
• An enzymatic cleaner made for pet urine
• A blacklight, to find old stains
• Baking soda, for deodorizing
• A wet vacuum, if available
• Plastic wrap or a bowl to cover the area

Fresh accidents on carpet

1. Blot with paper towels, pressing firmly. Do not rub.
2. Rinse with cool water, and blot again.
3. Saturate the spot with enzymatic cleaner, allowing it to soak as deeply as the urine did.
4. Cover with plastic wrap or a damp towel to keep it moist, as directed.
5. Wait, following the product directions, often several hours.
6. Blot or extract the excess, then let it dry completely.
7. Repeat if odor remains.

Do not use steam cleaners, which can set the stain and odor.

Old stains

Use a blacklight in the dark to find dried urine, which glows. Mark the spots. Treat each with enzymatic cleaner. Large or repeated soakings may have penetrated carpet pad or floorboards, which may need treatment or replacement.

Hard floors and tile

Wipe up urine, clean with enzymatic cleaner and let it dry. Check grout and seams, where urine can seep. Seal unfinished wood after cleaning.

Upholstery and mattresses

• Blot the area, and apply enzymatic cleaner.
• Test on a hidden spot first.
• Let it dry fully.
• Sprinkle baking soda to absorb odor, then vacuum.
• Consider professional cleaning for large items.

Laundry

Pre-soak items in enzymatic cleaner, then wash with detergent. Do not dry until the smell is gone, since heat can set odor.

What to avoid

• Ammonia-based cleaners. They smell like urine and may encourage re-marking.
• Bleach, which is toxic and can create harmful fumes with urine.
• Steam cleaners on fresh stains.
• Strong fragrances, which mask but do not remove odor.
• Punishing the cat. It does not help, and it increases stress.

Vinegar can help with light odors but does not replace an enzyme cleaner.

Stop repeat accidents

• Clean the litter box more often. See how often to clean a litter box.
• Review litter, box type and location. See litter box types compared and where to put the litter box.
• Block access to the spot, or place a food bowl or cat bed there.
• Add boxes in multi-cat homes. See how to introduce a new cat to your cat.
• Reduce stress and provide enrichment. See indoor cat enrichment ideas.
• Ask your vet about spraying and marking. See when to spay or neuter a kitten.

Dealing with sprayed walls and vertical spots

Spraying leaves urine on vertical surfaces, such as walls, doors and furniture. Wipe with enzyme cleaner, and let it work for the time on the label. Repaint with a stain-blocking primer if the smell persists. Block your cat's access to the area, and reduce stress that may drive marking. Ask your vet about spraying, especially in unneutered cats.

Subfloors and pads

If urine has soaked through carpet to the pad or subfloor, surface cleaning will not be enough. You may need to lift the carpet, treat the subfloor with enzymatic cleaner, seal it with a stain-blocking sealer and replace the pad. It is more work, but it is the surest way to remove deep odor.

Prevention

A clean, appealing litter setup and a healthy, stress-free cat prevent most accidents. Keep enzyme cleaner on hand, and treat accidents immediately.