Your sofa cushions smell musty for a reason: the pillowcase trick hotel cleaners use to freshen them without spray

The living room looked clean enough: hoover tracks on the rug, folded throw, yesterday’s mugs gone. Yet every time I sat down, there it was – a faint, damp sweetness rising from the sofa cushions, the smell of guest rooms that haven’t seen fresh air in a while. I lit candles, opened a window, even sprayed a fabric freshener I knew would give me a headache. For ten minutes it smelt of perfume. Then the mustiness crept back, stubborn as ever.

A friend who used to run housekeeping in a city hotel laughed when I mentioned it. “You’re treating the air, not the cushions,” she said. “They’re sponges. You have to squeeze the room out of them.” I pictured industrial products and secret hotel-only sprays. Instead, she handed me an old cotton pillowcase and showed me a trick their team use between deep cleans. No chemicals. No special kit. Just fabric, movement and time.

Why your cushions smell older than they are

Cushions live where people exhale. They collect breath, skin cells, body oils, crumbs, pet dander and the odd splash of tea. The covers might see the washing machine once in a while, but the pads inside rarely do. Foam and feather are both porous; they absorb moisture on humid days, then hold on to it long after the room feels dry.

That slow, trapped damp is what your nose reads as “musty”. It’s not always full-blown mould – often it’s just stale air and microscopic growth having a quiet party in the stuffing. Under evening lamplight you smell comfort and fabric softener. Under morning light, when the room is cooler and still, the odour stands up and introduces itself.

Sprays can mask it for a bit, yet they mostly perfume the surface. The problem sits deeper, in the air pockets wedged inside the cushion. Think of it like a cardigan that’s never properly aired between wears: fresh on the outside, slightly “old cupboard” underneath. To fix it, you don’t need a stronger scent. You need a way to push clean air right through the pad and take the stale with it.

The pillowcase trick hotel cleaners swear by

The trick is disarmingly simple: treat each cushion like a pillow you’re about to store, and let a cotton case do the dirty work for you. In hotels, this happens fast in the background, between checkout and the next check-in. At home, you can stretch it into a quiet half-hour and a cup of tea.

Here’s how to do it.

1. Strip what you can
   If your cushion covers are removable, unzip them and slide them off. Check the care label and pop the covers in the wash, following the gentlest instructions it suggests. Skip fabric softener if you can; it can leave a film that holds on to odours.

2. Bag the inner in a pillowcase
   Take a clean, old cotton pillowcase – plain, no embellishments – and feed the cushion pad inside. If it’s a big seat cushion, you may need a king-size case or to use one on each end. Twist or loosely knot the open end so the pad is fully enclosed but not strangled.

3. Choose your method: breeze or drum

• Outside, no tumble dryer:
  Take the bagged cushion outdoors and give it a series of firm pats and shakes, working along the edges. The pillowcase catches the dust and fine debris, so it doesn’t blow back in your face or all over the garden. Lay the cushion down in the shade or bright indirect light – not full, harsh sun – and leave it for at least 30–60 minutes on each side to air.

• With a tumble dryer, no spray:
  Pop the pillowcased cushion into the dryer on a cool or air-only setting. Add a couple of clean, dry towels or dryer balls to help beat air through the pad. Tumble for 20–30 minutes. If you like a subtle scent, you can tuck a dry cotton flannel with a drop or two of essential oil into the drum – not on the cushion itself.

1. Let the pillowcase do its job
   As you beat or tumble, the cotton works like a filter bag. Dust, loose fibres and a surprising amount of stale-smelling fluff migrate into the pillowcase. The pad itself gets aerated, fluffed and gently warmed, which helps drive out lingering damp.

2. Check, repeat, then reunite
   Take the cushion out of the pillowcase and sniff deeply. If it still smells a bit flat, give it another round of air or a second 15-minute tumble. Once you’re happy, slide it back into its cover (dry and cool from the wash), plump it, and let it settle before you sit.

The whole thing feels a little too easy, like you’ve missed a step. You haven’t. You’ve simply given the cushion what it actually needed: fresh air, movement and a clean cloth to carry the grime away.

Why a pillowcase works better than a spray

A spray works on the outside centimetre of the cushion. The pillowcase trick reaches the middle. Cotton is breathable, so air can move in and out freely, but its weave is tight enough to trap the fine dust and lint that make upholstery smell “heavy”.

When you pat, shake or tumble, you’re doing three things at once:

• Agitating the filling, so clumped areas loosen and stale pockets open up.
• Pushing air through the pad, swapping humid air for drier, fresher air.
• Catching the fallout, so spent fluff and dust end up in the case, not your lungs.

Hotel staff like it because it’s quick, it doesn’t wet the fabric, and it avoids drenching rooms in competing fragrances. At home, it means you can freshen cushions even when someone is sensitive to scents or asthma is in the picture.

If you peek inside the pillowcase afterwards, you’ll often see light grey dust rings or tiny fibres at the seams. That’s what your nose was complaining about.

Small extras that make a big difference

The pillowcase trick does the heavy lifting, but a few small habits help keep that mustiness from creeping back.

• Vacuum before you bag
  Run the upholstery nozzle over the bare cushion pad, paying attention to seams and buttons. This removes crumbs and hair so the pillowcase can focus on the fine stuff.

• Use bicarbonate of soda on fixed cushions
  If your seat cushions don’t come off, sprinkle a light dusting of bicarbonate of soda over the surface, work it in gently with your hand, leave for 30–60 minutes, then vacuum thoroughly. It helps absorb surface odours between deeper refreshes.

• Let airflow do some of the cleaning
  Once a month, pull the sofa a little way from the wall and stand the cushions on their sides for an afternoon. It looks odd, but it lets air circulate where damp often lingers.

• Rotate and flip
  Swap cushions around and flip them weekly if you can. It evens out wear and reduces the chance of one “favourite spot” becoming the permanently musty one.

Here’s a quick guide to match issues with simple fixes:

Issue	What you’ll notice	First fix to try
Light musty smell, no visible marks	Sofa smells “old” when you sit, better with window open	Pillowcase trick + airing in shade
Pet and snack odours	Whiffs of dog, biscuits or stale crisps	Vacuum, bicarbonate on covers, then pillowcase refresh
One cushion smells worse	Localised odour, often where someone naps	Deep refresh that pad + wash cover, rotate positions

Safety notes and when to stop

Not every cushion wants a tumble dryer. Check the care label on both cover and inner. Feather and many synthetic fills cope well with a cool tumble inside a pillowcase. Solid foam can sometimes warp with heat or heavy beating, so stick to gentle outdoor shaking and shade-drying there.

If you see black spotting, slimy patches or you get a sharp, sour smell when you press the cushion, you may be dealing with actual mould rather than general mustiness. In that case, airing and pillowcases won’t be enough. You’ll need to decide whether the pad can be professionally cleaned or whether it’s time to replace it. There’s no point sealing a health problem back into the sofa.

Most of the time, though, the issue is old air, not disaster. One quiet afternoon with a pile of pillowcases can reset the whole room.

FAQ:

• How often should I do the pillowcase trick on sofa cushions?
  For a busy family sofa, every 2–3 months works well, with quick vacuums in between. Guest room sofas or rarely used armchairs can go longer and just be done before visitors.
• Can I add fragrance without using a spray?
  Yes. Either wash the pillowcases in a lightly scented detergent before using them, or pop a dry cloth with a drop of essential oil into the tumble dryer. Keep oils away from the cushion fabric itself to avoid staining.
• Does this replace washing the covers?
  No. The pillowcase trick targets the cushion inner. Wash removable covers as the label allows, especially if there are visible marks or spills.
• Will it work if I don’t have any outdoor space?
  Absolutely. Use the cool tumble method, or stand pillowcased cushions near an open window or in a breezy hallway and beat them gently. The key is movement and airflow, not sunshine.
• What if my cushions are attached and can’t be removed?
  You can’t bag the pads, but you can still copy the principle: vacuum thoroughly, sprinkle bicarbonate, vacuum again, then open windows and give the cushions a firm pat-down to move air through them.