How to Clean a Mattress: Stains, Smells and a Proper Deep Clean
To clean a mattress, strip and wash the bedding, vacuum the whole mattress with the upholstery tool, spot-clean any stains with a damp (never wet) cloth and the right cleaner for the stain, sprinkle bicarbonate of soda over the surface and leave it for a few hours, then vacuum it off and let the mattress air until it's completely dry.
That's the routine. Below: what to use on each kind of stain (including the ones children specialise in), what to do with bunk beds and high sleepers, how often to do it, and when a mattress isn't worth saving.
What you'll need
- A vacuum with an upholstery attachment
- Bicarbonate of soda
- White vinegar and a spray bottle
- Washing-up liquid
- An enzyme cleaner (from supermarkets or pet shops)
- Clean white cloths or towels
Skip bleach. Skip fragranced powders and essential oils in a child's room too: they can irritate young skin and airways, and oils can mark the fabric.
Deep cleaning a mattress, step by step
Step 1. Strip the bed. Wash the sheets, pillowcases and mattress protector at 60°C if the care labels allow, which kills dust mites.
Step 2. Vacuum everything. The top, the sides and especially the seams and edges, where dust and skin cells collect.
Step 3. Spot-clean any stains. Work from the outside of the stain inwards, blot rather than rub, and keep it damp rather than wet. See the stain guide below.
Step 4. Deodorise. Sprinkle bicarbonate of soda over the whole surface and leave it for at least a few hours, ideally overnight.
Step 5. Vacuum again to lift the bicarbonate and the odours it's absorbed.
Step 6. Dry it fully. Open a window and let the air circulate. The mattress must be completely dry before any bedding goes back on, or you're trapping moisture that turns into mould.
Only machine-wash a mattress cover if the care label says it's removable and washable. On many mattresses the cover is part of the fire-safety construction and isn't designed to come off.
How to get stains out of a mattress
Urine. Blot straight away, then use a vinegar solution and bicarbonate of soda, and an enzyme cleaner if the smell comes back. Our guide to getting urine smell out of a mattress takes you through it step by step.
Vomit. Scrape off anything solid, blot, then cover with bicarbonate of soda for an hour to draw out the moisture and smell. Vacuum it up, dab with a few drops of washing-up liquid in cold water, and blot dry. Finish with an enzyme cleaner if any smell lingers.
Blood. Cold water only: hot water sets blood for good. Blot with a cold, damp cloth. For anything stubborn, dab on a little hydrogen peroxide, let it fizz, and blot. Patch test it on a hidden corner first, as it can lighten some fabrics.
Sweat and yellow marks. Spray lightly with equal parts white vinegar and water, leave for ten minutes, and blot. Older yellowing may need a second go, or a careful dab of hydrogen peroxide.
Juice, milk and squash. Blot, then dab with cold water and a drop of washing-up liquid. Milk is protein, so if it starts to smell sour, follow up with an enzyme cleaner.
Felt tip and pen. Dab, don't rub, with a cotton wool pad and a little surgical spirit, then blot with a damp cloth. Patch test first.
Whatever the stain, never mix cleaning products, especially vinegar with hydrogen peroxide, or anything with bleach.
Memory foam and sprung mattresses: what's different
Memory foam soaks up liquid fast and dries slowly, so use even less moisture and allow a full day of drying. Don't use a steam cleaner on foam. Sprung mattresses are more forgiving, but the same rule applies: damp, never wet.
Bunk beds and high sleepers
Don't clean a mattress in place on a top bunk or high sleeper. Water can run into the frame, and leaning over a guard rail with a spray bottle is how people fall. Take the mattress down to the floor, clean it there, and let it dry flat.
While it's down, it's a good moment to check the bed itself: tighten any loose bolts and make sure the slats are sound. If you're replacing the mattress, stay within the bed's maximum mattress depth so the guard rail keeps doing its job. Our bunk bed mattress guide explains sizes and depths.
Keeping it clean for longer
Use a protector. A washable waterproof mattress protector stops sweat, spills and accidents reaching the mattress at all. It's the cheapest way to make a mattress last.
Rotate it. Turn the mattress head to foot every three months or so, so it wears evenly. Only flip it over if the label says it's two-sided.
Air it out. When you change the sheets, leave the mattress uncovered for an hour or two.
Keep food and drink out of bed. Easier said than done with children, but it prevents most stains.
If night-time accidents are regular, a protector can struggle. The DryComfort 15 is waterproof all the way through, so nothing reaches the foam.
How often should you clean a mattress?
- Weekly: wash the bedding.
- Monthly: vacuum the mattress.
- Every three to six months: a full deep clean with bicarbonate of soda, and rotate it.
- Straight away: any spill or accident, before it soaks in.
If anyone in the house has allergies or asthma, vacuum more often and wash bedding at 60°C. If dust mites are a problem, our hypoallergenic mattresses are worth a look.
When cleaning isn't enough
Replace a mattress if:
- it sags or has dips your child rolls into
- a smell keeps coming back after two or three thorough cleans
- there's mould, or staining under the cover
- it's torn or lumpy
- it's more than seven or eight years old
More on this in how often you should change a mattress. When it's time, you'll find all our kids' mattresses here.
Common questions
Can I use a steam cleaner on a mattress? Not on memory foam, and check the manufacturer's advice for other types. Heat and moisture can damage foam and leave damp behind.
Is bicarbonate of soda safe on a child's mattress? Yes. It's gentle and unscented. Just vacuum it all off before you make the bed.
How long does a mattress take to dry? A few hours after light spot-cleaning, and up to a full day for foam or anything that got properly wet. Don't make the bed until it's completely dry.
Can I use washing powder or carpet shampoo? Stick to a few drops of washing-up liquid. Detergents and shampoos leave a residue that attracts dirt and is hard to rinse out of a mattress.
Should I get a mattress professionally cleaned? It's rarely worth it for a child's mattress. If it's got to that point, it's usually time to replace it.
