Whether the culprit is your child, a pet or someone else, urine on a couch cushion is a messy thing to deal with. Fortunately, there are a few tips and tricks that allow you to clean the urine up and prevent any long term smells. The key is to clean the urine up immediately and as thoroughly as possible.
Remove the cushion cover from the actual cushion if you can. Many have zippers that allow you to remove it, but if yours doesn't, don't worry. Either way, the following steps will still work.
Soak up the excess urine with a dry towel by gently dabbing it around the affected area. During this process you want the towel to absorb the urine, so don't press too hard. When the towel becomes damp, trade it out for a fresh, dry towel.
Mix two cups of hydrogen peroxide with a teaspoon of liquid soap or upholstery-friendly cleaner and two tablespoons of baking soda in a bucket. Stir these three items together until the baking soda is fully dissolved.
Apply the mixture to a sponge and gently scrub the area. Spread it out evenly across the area and let it set for a half hour.
Remove the solution with a clean, damp towel. Make sure you pick up all the cleaning residue and rinse and wring out the towel often.
Let the cushion cover (or cushion if you could not remove the cover) air dry for at least 24 hours before using it again.
Repeat the process one or two more times if necessary to ensure that all the urine has been removed and the smell eliminated.