Depending on the cat and the circumstance, they may occasionally forget or disregard its litter box all together. Cat urine is one of the most pungent smells on earth. It can even discolor fabric, so it needs to be attended to as quickly as possible. Not only is the smell awful for humans, cats will urinate in the same place if it isn't cleaned up. Cleaning cat pee off the couch is unpleasant, but easy.
For Couch Cushions
Blot up as much of the urine as you can with paper towels.
Remove the cover from the seat and put it in the washing machine.
Add a cup of vinegar to the rinse cycle.
Sprinkle baking soda on the soiled area of the cushion and let it sit for at least 2 hours to draw the moisture out.
Brush the baking soda into the garbage and mix a solution of vinegar and water, in equal parts, in a spray bottle.
Spray the area and scrub with a cloth or paper towel. Set the cushion aside to dry.
Put the cover in the dryer. When both cushion and cover are dry, put the cover back on the couch.
For the Couch
Blot up as much of the urine as you can with a paper towel.
Mix a solution of vinegar and water, in equal parts, in a spray bottle.
Spray the area with the solution and scrub gently with a clean cloth or paper towel.
Allow the area to dry completely. If the smell persists, sprinkle baking soda onto the area and let it sit for at least an hour.
Vacuum up the baking soda.