How to Get Urine Smell Out of a Mattress (That Actually Works)

To get urine out of a mattress, blot up as much as you can, treat the area with an enzyme cleaner (or a vinegar solution), cover it with baking soda for several hours, vacuum, then dry it completely. The key is reaching the urine that has soaked below the surface, because that’s what causes the smell to come back.

What you need

• Paper towels or old towels
• An enzyme-based urine cleaner (from pet shops or supermarkets), or white vinegar and water
• Baking soda
• A spray bottle, a vacuum, and a fan or dehumidifier

Step by step

1. Strip the bed and wash the sheets and protector separately.
2. Blot, don’t rub. Press dry towels firmly on the wet area and stand on them if needed. Rubbing spreads the urine.
3. Apply enzyme cleaner generously over the stain and a few centimetres beyond its edge, since urine spreads wider below than on top. Leave it for the time on the label, usually 15 to 30 minutes. No enzyme cleaner? Mix 1 part white vinegar to 1 part water, spray and blot.
4. Blot again to lift out the cleaner and the dissolved urine.
5. Cover with baking soda in a thick layer and leave it 8 hours or overnight. It absorbs moisture and odour.
6. Vacuum up all the baking soda.
7. Dry completely with a fan, the aircon or a dehumidifier. A damp mattress in Singapore’s humidity will smell again and can grow mould.

What not to do

• Don’t use hot water or steam on fresh urine. Heat can bind the proteins and set the smell.
• Don’t use bleach or ammonia cleaners. They damage the fabric, and ammonia smells like urine to pets.
• Don’t soak the mattress. Too much liquid drives urine deeper into the foam.
• Don’t just spray fabric freshener. It masks the smell for a day.

Why the smell comes back

Urine contains uric acid crystals that surface cleaners don’t dissolve. When humidity rises, which in Singapore means most days, the crystals re-activate and release the smell again. That’s why old or repeated accidents usually need enzyme treatment plus extraction, which flushes the residue out of the foam rather than leaving it there.

When to call a professional

• The smell comes back after you’ve tried the steps above
• It’s an old stain, or there have been repeated accidents in the same spot
• The urine went through the protector into the foam
• You can see a yellow ring that keeps growing

We treat urine in mattresses, sofas and carpets with enzyme treatment and hot-water extraction. See urine stain and odour removal or mattress cleaning.