How to Clean a Mattress That Has Been Urinated On

13 min read. Updated October 9, 2026.

Urine is mostly water, but it also carries urea and uric acid. When the water evaporates, those solids dry into the fabric and foam, and that residue is where the sharp ammonia smell comes from. Whether a toddler, an older parent or a cat made the mess, the job is to lift the liquid, break down the residue and dry the mattress before mould starts. Mattress Miracle, a family-owned store in Brantford since 1997, sells mattress protectors in 11 styles from $32. A waterproof one turns the next accident into a load of laundry.

An enzyme cleaner is a spray that contains enzymes, proteins that break down the organic compounds in urine that plain soap and water leave behind. Humane World for Animals says enzymatic cleaners break down pet waste odours.

Two rules come before any step. Never mix bleach with ammonia or with an acid such as vinegar, because Health Canada warns the combination releases toxic gas. And never soak the mattress, since Health Canada's mould guide says mould can begin to grow within 48 hours in an area with excessive moisture. If you buy one thing after reading this, make it a waterproof mattress protector that goes in the washing machine.

How Can I Get Urine Out of a Mattress? Step by Step

Getting urine out of a mattress takes six steps and most of a day, and speed matters more than the product. The sooner the liquid comes off the surface, the less reaches the foam. These steps cover a fresh accident; dried stains have their own section.

The same powder freshens a mattress with no accident at all, and our guide to cleaning a mattress with baking soda walks through that version.

What you need to get urine out of a mattress

Supply	Job	Notes
Clean white cloths or paper towels	Blotting	White avoids dye transfer; use many
Enzyme cleaner	Breaks down urine residue	Made to break down urine; follow the label
White distilled vinegar	Fresh human urine, odour	Mix 1:1 with cold water in a spray bottle
Baking soda	Draws out moisture and odour	Needs at least 8 hours
3% hydrogen peroxide	Old yellow stains	Pharmacy strength; patch-test first
Cold water	Dilutes and rinses	Never hot; heat sets the stain
Rubber gloves	Protects your skin	Health Canada advises gloves with cleaning products
Vacuum with upholstery tool	Lifts dried baking soda	Go slowly
Fan or open window	Drying and fresh air	A damp mattress can grow mould

Step 1: Strip the bed and blot right away

Pull off the sheets, the protector and any foam or latex mattress topper, since a topper soaks up urine the same way a mattress does. Press a folded white cloth firmly onto the wet area, hold it a few seconds, then move to a dry part of the cloth. Never rub, because rubbing pushes urine deeper into the fibres.

Step 2: Spray an enzyme cleaner or the vinegar mix

Spray the cleaner across the stain and a little past its edges, since urine spreads as it soaks in. With no enzyme cleaner on hand, a 1:1 mix of cold water and white vinegar works on a fresh human accident. Dampen the surface without soaking it, then wait 10 to 15 minutes. The Sleep Foundation's urine guide gives its vinegar solution 15 minutes. Vinegar is for human urine only; for a pet accident, our cat urine mattress guide explains why an enzyme cleaner works better.

Step 3: Blot again

Press clean, dry cloths onto the area to lift the cleaner and the urine it loosened.

Step 4: Cover the spot with baking soda for at least 8 hours

Spread baking soda a few millimetres thick over the damp area to pull out moisture and absorb odour. The Sleep Foundation recommends at least 8 hours; overnight is better, and a full day suits a large accident.

Step 5: Vacuum and inspect

Vacuum the powder slowly, then check the spot in daylight. If a faint ring or smell remains, repeat Steps 2 to 4; most fresh stains clear in one or two rounds. Sweat leaves a similar yellow mark, and our sweat stain guide treats that one.

Step 6: Dry the mattress completely before making the bed

Put a fan over the area and open a window. Give it at least 2 to 4 hours of moving air before the sheets go back on, longer in humid weather. If the spot feels cool or damp to the back of your hand, keep the fan running. Aim for fully dry inside the 48 hours Health Canada gives for mould to start.

Is Vinegar or Hydrogen Peroxide Better for Urine?

Vinegar is the better first pass on fresh human urine, and 3% hydrogen peroxide is better on old yellow stains on white or cream fabric. An enzyme cleaner beats both on stubborn odour and on pet urine. Never use vinegar and hydrogen peroxide at the same time: Transport Canada's CANUTEC guidance on mixing cleaners warns that together they form peroxyacetic acid, which is corrosive and toxic. Finish one, let the mattress dry, and only then try the other.

Peroxide can bleach a coloured cover, whether it is a quilted top or the stretch-knit cover on a rolled mattress-in-a-box model, so test it on a hidden corner first.

Urine cleaners compared

Cleaner	Best for	Contact time	Watch for
Enzyme cleaner	Fresh or dried urine, pet urine, odour that returns	10 to 20 minutes, longer for pets	Keep it damp while it works; follow the label
White vinegar and cold water, 1:1	Fresh human urine	10 to 15 minutes	Never with bleach or peroxide; can draw pets back to the spot
3% hydrogen peroxide paste	Old yellow stains on light ticking	10 minutes	Can lighten coloured fabric and damage foam or latex
Baking soda	Drawing out moisture and smell	8 hours or more	Vacuum every bit of it

Cleaner Safety: Never Mix Bleach, and Air the Room Out

Urine cleanup uses ordinary household products, and the danger comes from combining them. Health Canada's 2021 bleach advisory says bleach reacts with any product containing ammonia or an acid, including vinegar, and can release toxic gases such as chloramine. The effects range from burning eyes and light-headedness to death. The Sleep Foundation's urine guide also says not to clean a mattress with bleach at all.

• Never mix bleach with vinegar, ammonia, glass cleaner or toilet bowl cleaner, and never add bleach to a wash load with vinegar in it.
• Use vinegar and hydrogen peroxide on separate passes, never together.
• Open a window or run a fan during and after cleaning, as Health Canada advises, and wear rubber gloves.
• Patch-test every cleaner on a hidden corner and let it dry before you judge the colour.
• Spray lightly and never soak foam. Liquid deep in foam can't be blotted back out.
• Keep children and pets out of the room until the mattress is dry and the cleaner smell has gone.

If someone breathes in fumes from mixed cleaners or swallows one, call a poison centre at 1-844-764-7669 (1-844-POISON-X; in Quebec, 1-800-463-5060). If the person is unconscious, not breathing or having a seizure, call 911.

How to Remove Dried Pee From a Mattress

A dried urine stain needs rehydrating before any cleaner can reach it. When pee dries in a mattress, the water leaves and the residue crystallises in the fibres, often as a yellow ring. Expect more than one round. If the stain is old and the mattress also sags, our guide on when to replace a mattress in Canada may be the more useful read.

1. Find the whole stain. A UV blacklight flashlight shows dried urine as a glowing patch, and Humane World for Animals' stain guide suggests outlining it lightly with chalk.
2. Mist it with cold water until the surface is damp, never soaked, to soften the residue.
3. Work in an enzyme cleaner and give it 15 to 20 minutes under a damp cloth, which keeps the enzymes working longer. Blot it out.
4. For yellowing that remains, mix 120 ml (half a cup) of 3% hydrogen peroxide, one tablespoon of baking soda and one teaspoon of dish soap in an open bowl. Work a little in, wait 10 minutes and blot. Skip this on latex, and only use it once any vinegar has dried.
5. Cover the area with baking soda for 10 to 12 hours, then vacuum. A stain that sat for months may need several rounds.

Cold water is also the first rinse for the sheets, duvet cover and pillowcases that were on the bed, and never add bleach to a load with vinegar in it. If a set is past saving, our bed sheet collection has cotton, bamboo and linen replacements, and we carry linen duvet covers and cotton, linen and silk pillowcases too.

How to Get Urine Smell Out of a Mattress

Urine smell can linger after the stain is gone, and it often returns on warm, humid nights when leftover residue gives off ammonia again. The fix is another round of enzyme cleaner and more drying time.

• On human urine, mist a 1:1 vinegar and water mix lightly and let it air-dry; the vinegar smell fades as it dries. Skip vinegar on pet accidents.
• When the smell is spread across the bed, cover the whole surface with baking soda for 24 hours, then vacuum.
• For odour that keeps coming back, apply an enzyme cleaner, lay a damp cloth over it and give it the label's full contact time.
• Sunlight and moving air help the cover dry and air out, but they don't reach residue deep in the foam.

For an older, musty smell with no single source, our musty mattress deodorizing guide goes further. On humid nights, a breathable sheet over the protector helps the surface dry between washes, and our cotton bed sheets are the plain choice.

How to Clean Pee Out of a Memory Foam Mattress and Other Types

A memory foam mattress is the hardest to clean because open-cell foam wicks liquid inward and holds it. The Sleep Foundation notes that all-foam beds can hold urine smell more than other mattresses. That is worth knowing before you choose from the foam mattresses on the Mattress Miracle floor. If you aren't sure what is inside yours, our mattress range in Brantford shows the foam, hybrid and coil builds we carry.

Cleaning urine by mattress type

Mattress type	What matters	Change to the method
Innerspring	Coils let air move through the core	Standard method; allow extra drying time
Memory foam	Absorbs and holds liquid deep down	Use the least liquid possible; dilute peroxide 1:1 with water; press, never wring
Latex	Can be damaged by harsh chemicals	Skip hydrogen peroxide; use enzyme cleaner and the vinegar mix
Hybrid	Foam layers on top, coils below	Treat the top like memory foam; the coil core dries faster
Pillow top	An extra padded layer holds odour	Treat the pillow top and the layer under it; dry longer

On memory foam, dab the cleaner on. After blotting, weigh a stack of dry cloths down with a heavy book to draw moisture back up. Change the cloths every 20 to 30 minutes until they come away dry, then stand the mattress on its side so air reaches both faces. Our memory foam mattress cleaning guide covers everyday care, and our deep-cleaning method for a whole mattress covers the twice-a-year job.

A two-sided flippable mattress can be turned to its dry side while the wet side airs out. Once it is back down, a platform bed frame keeps the mattress up off the floor, where air can reach the underside.

Getting Pet Urine Out of a Mattress

Pet urine needs a different approach. The Sleep Foundation and Humane World for Animals both point to an enzyme cleaner made for pet messes. Humane World advises against ammonia or vinegar on pet accidents, because strong chemical smells may encourage the animal to mark the same spot again.

Map the area with a blacklight first, since pet accidents are often several small spots. Give the enzyme cleaner 20 to 30 minutes, then apply it again after the first round of baking soda. If a cat keeps coming back, a zippered six-sided encasement covers the sides and underside that a fitted protector leaves open.

What Not to Do When Cleaning Urine From a Mattress

• Don't use hot water. Heat sets the stain and brings the odour back.
• Don't use ammonia-based cleaners. Urine already gives off ammonia, so more of it strengthens the smell.
• Don't use bleach, and never mix it with vinegar or ammonia (see cleaner safety above).
• Don't steam clean. Humane World for Animals warns that the heat will permanently set the stain and the odour by bonding the protein into man-made fibres.
• Don't rub. Always blot.
• Don't soak the mattress or remake the bed while it is damp, since damp padding is where mould starts. Health Canada says people in damp, mouldy homes are more likely to have eye, nose and throat irritation, coughing, wheezing and worse asthma.
• Don't rely on scented sprays. The odour returns when the room warms up.

Is a Mattress Ruined if It Gets Peed On?

A mattress that gets peed on once is usually not ruined. A single accident cleaned the same day and dried within a day or two normally leaves no stain or smell. Replacement makes sense in a few cases:

• It was soaked repeatedly over months without cleaning, and the urine has reached the core.
• You can see or smell mould, a musty, earthy odour different from urine. Health Canada's mould guide says it is not possible to properly clean a mouldy mattress.
• It is eight to ten years old and was already wearing out.
• Several deep cleans have not removed the smell.

If replacement is the answer, our page on how our mattress prices work shows what a new bed costs before you visit. Stains also matter for exchanges at Mattress Miracle. Our 60-Night Comfort Guarantee terms say the mattress must be like-new, free of stains or damage, and that use of a mattress protector is required. For a manufacturer's warranty, read that brand's warranty card. If you can't tell whether your mattress can be saved, call us or send a photo, and if cleaning will do the job, we will say so.

Preventing Future Accidents With a Waterproof Mattress Protector

A waterproof mattress protector keeps urine out of the mattress itself. A thin membrane, usually polyurethane or TPU, sits under a fabric top, so liquid never reaches the foam or springs, and the protector goes in the washing machine. Mattress Miracle stocks these in Brantford today:

Waterproof protectors at Mattress Miracle (prices checked October 9, 2026)

Protector	Style	Fits mattresses up to	Twin to king
Health Guard Basic Protection	Fitted, waterproof barrier	15 inches deep	$32 to $49
Health Guard Bamboo Plus	Fitted, bamboo top, waterproof membrane	18 inches deep	$43 to $65
Rise Sleep Essential Waterproof	Fitted, cotton terry top	18 inches deep	$65 to $97
Health Guard Barrier Guard	Zippered encasement, all six sides	16 inches deep	$49 to $80

Families in toilet training often put a protector on every bed, because accidents turn up in unexpected places. Our guide to choosing a kids mattress protector covers fabrics and fit, and our kids and teens mattress page lists sizes by bed. Caregivers can read our incontinence and waterproof bed guide for a full setup. With allergies or asthma, pair the protector with regular washing; for the rest of the bedroom, our guide to improving sleep quality covers temperature, darkness and sleep habits.

Look for "waterproof" on the label, since "water resistant" only slows liquid. A fitted protector covers the top and sides; an encasement zips around all six. Match the depth, because a shallow protector pops off the corners. Our mattress size chart covers width and length only, so measure the depth yourself. To compare more brands, our best mattress protector guide for Canada lines them up.

Wash the protector itself in cool water, because heat can damage its waterproof layer. Our answer to whether a mattress protector can be washed covers how to wash and dry one.

Visit Our Brantford Showroom

We are at 441 1/2 West Street, in Brantford since 1997 and on West Street since 2010. Parking is free, right at the store. Our advisors don't work on commission.

Mattress Miracle, 441 1/2 West Street, Brantford, ON, (519) 770-0001

Hours: Monday to Wednesday 10am to 6pm, Thursday and Friday 10am to 7pm, Saturday 10am to 5pm, Sunday 12pm to 4pm.

If the stain or smell won't come out, stop by. We carry waterproof mattress protectors that keep the next accident out of the mattress, and we can help you find a replacement if you need one.