How do I clean up a pet accident properly?

Removing the smell entirely, which is what stops the animal returning to the same spot.

Difficulty: beginner
Time: 45 min
Read: 2 min

Short answer

Blot rather than rub, then use an enzymatic cleaner made for pet accidents — ordinary detergent does not break down the compounds that cause the smell. Never use anything containing ammonia; it smells like urine to the animal and encourages repetition.

Two things matter: removing the liquid before it soaks into the underlay, and destroying the residue chemically. If any smell remains, and an animal's sense of smell far exceeds yours, the spot is marked as a toilet.

What you'll need

Kitchen paper or old towels
Enzymatic pet cleaner
Gloves
Cold water (optional)

Step by step

Blot up as much liquid as possible immediately.Press with kitchen paper or towels. Standing on a thick pad of paper works well. Speed matters more than technique here.
Do not rub or scrub.Rubbing pushes the liquid deeper into the carpet pile and the underlay, and damages the fibres.
Rinse with cold water and blot again.Cold, not hot. Heat sets protein stains and makes both the mark and the smell permanent.
Apply an enzymatic pet cleaner generously.It must reach as deep as the liquid did — this usually means using more than feels reasonable. The enzymes break down the compounds causing the odour.
Leave it to work for the stated time.Usually ten to fifteen minutes, sometimes longer. Enzymes need contact time; wiping straight away defeats the purpose.
Blot dry and let it air dry fully.Cover the area so the animal cannot return to it while it dries. A fan speeds this up considerably.
Never use ammonia-based cleaners.Ammonia is a component of urine. To an animal the area now smells strongly like a toilet, which is the opposite of the intention.
Check with your nose at floor level once dry.If any smell remains, repeat. Residual odour is what causes repeat accidents in the same place.

Tips

Keep enzymatic cleaner in the house before you need it. The first hour makes an enormous difference and a trip to the shop wastes it.
Repeated accidents in the same spot, or a change in an animal's toileting, can indicate a medical problem. It is worth a vet check rather than only a cleaning response.
For a large soak-through, the underlay may need lifting or replacing. Cleaning the surface alone will not remove the smell if the liquid went beneath.

Common mistakes

Using ordinary detergent or carpet shampoo — It cleans the visible stain but leaves the odour compounds, and the animal returns to the same spot.
Using hot water — Heat sets protein-based stains permanently and bonds the odour into the fibres.
Using an ammonia-based cleaner — Ammonia smells like urine to the animal, which actively marks the area as a toilet.

Questions people ask

What is the best cleaner for pet urine?

An enzymatic cleaner specifically formulated for pet accidents. Enzymes break down the compounds causing the smell, which ordinary detergents leave behind.

Why does my pet keep going in the same place?

Because they can still smell it, even when you cannot. Any residual odour marks the spot as a toilet. If cleaning thoroughly does not stop it, a vet check is worthwhile.