Goodbye shoe odour: How to properly clean fixed insoles

Wearing trainers, smart shoes or sneakers with fixed insoles comes with a familiar frustration: the uppers still look brilliant, but inside the shoe smells like a changing room. With the right approach you can clean fixed insoles thoroughly, cut down bacteria, and rescue the shoe-without wrecking the glue, cushioning or shape.

Why fixed insoles are a special challenge

With removable insoles, the job is straightforward: take them out, wash, dry, done. Fixed insoles are stitched or glued directly to the midsole. If you tug at them, you can easily damage the whole shoe structure.

There’s another issue: the footbed sits deep inside the shoe, so water, foam and cleaners don’t reach it easily-and any moisture you introduce takes much longer to evaporate. That mix of sweat, bacteria and lingering damp is exactly what creates stubborn odour and, over time, can make the materials degrade and become porous.

Fixed insoles always demand two things at once: as little water as possible, and as much hygiene as necessary.

What materials are inside fixed insoles in trainers and smart shoes?

Depending on the model, you may be standing on several layers:

• Foam or memory foam for soft cushioning
  
• Gel inserts in sports shoes for extra spring
  
• Textile or mesh top layers, often designed to wick moisture
  
• Leather surfaces in more formal footwear
  
• Sometimes antibacterial or odour-inhibiting coatings
  

Harsh chemicals or too much water can ruin these layers-loosening adhesive, breaking down coatings or causing foam to crumble. The rule of thumb is simple: keep it mild, targeted and controlled.

Basic clean: the step-by-step method

Before you use any moisture, clear out anything loose inside the shoe. The less grit you’re dealing with, the better your cleaner can do its job.

1) Remove dry dirt first

• Tap the shoes together to dislodge sand and dust.
  
• Brush the footbed with a soft brush or wipe with a dry cloth.
  
• Pay close attention to the toe area and around the edges.
  

This prevents you from smearing dirt around when you move on to damp cleaning.

2) Gentle clean with a soapy solution

In a bowl, combine warm water with a small amount of mild washing-up liquid or a dedicated shoe cleaner. Use very little-your mixture should look mostly clear, not frothy like bath foam.

• Dip a microfibre cloth or soft sponge into the solution.
  
• Wring it out firmly: it should be damp, never dripping.
  
• Wipe the insole using small circular motions.
  
• Work on stained or darkened areas more deliberately.
  
• Use a second cloth, lightly dampened with clean water, to lift off any soap residue.
  
• Finish by blotting moisture with kitchen roll or a clean towel.
  

The less liquid you introduce, the lower the risk of loosened glue and musty damp lingering inside the shoe.

3) Home remedy for strong odour: bicarbonate of soda & more

If the shoe already smells noticeably or has dark sweat marks, soapy water often won’t be enough. Bicarbonate of soda (not baking powder) is a gentle cleaner and odour absorber.

How to do a bicarbonate treatment:

• Mix a little bicarbonate of soda with a few drops of water to form a thick paste.
  
• Apply the paste directly to affected areas.
  
• Leave it for around 15 minutes.
  
• Wipe away carefully with a slightly damp cloth, lifting off any residue.
  

Bicarbonate of soda binds odour molecules and provides mild abrasion without being overly aggressive on foam and textiles.

Cleaning solutions compared

Different options suit different problems. Use this overview to choose the right approach:

Cleaning solution	Best for	Application	Typical drying time
Mild soapy solution	General grime	Damp cloth	24–48 hours
Bicarbonate of soda mix	Stains and strong odour	Targeted paste	12–24 hours
Alcohol–water mix	Disinfection	Spray or wipe	6–12 hours
Diluted white vinegar	Odour neutralising	Light mist	12–24 hours

Important: always test first in an inconspicuous spot to check the material stays colourfast and stable before treating the entire insole.

Extra option worth considering: if odour keeps returning quickly, an enzyme-based trainer cleaner can help break down sweat residues that standard soap leaves behind. Choose one designed for footwear, use it sparingly, and still avoid soaking the insole.

Drying properly: how to avoid mould and mustiness

After cleaning, drying is what decides whether your shoes stay fresh-or smell worse two days later. Direct heat is off-limits.

What you should avoid

• Putting shoes on a radiator
  
• Blasting the inside with a hairdryer
  
• “Quick-drying” in the oven
  

These heat shocks can soften glue, warp synthetic parts and make foam brittle.

Gentle drying, step by step

• Place shoes somewhere well ventilated and out of direct sunlight.
  
• A spot with gentle air movement is ideal-near an open window or in front of a fan.
  
• Stuff the shoes with newspaper or kitchen roll.
  
• Change the paper several times in the first few hours while it’s still damp.
  
• Leave the shoes for at least 24 hours; if they’re very damp, allow up to 48 hours.
  

Don’t wear them again until even the deepest part of the toe area feels completely dry.

If your home is very humid, put the shoes in a laundry bag and position them near a dehumidifier. This helps pull out trapped moisture much faster.

Another helpful hygiene boost: once the shoes are dry, a UV shoe sanitiser (or a short session in a well-ventilated, indirect-sunlight spot) can reduce bacteria without adding any moisture-useful for trainers that are worn hard.

Keeping shoes fresh between washes

Even the best clean won’t last long if the shoes go straight back into a closed cupboard while still slightly damp. A few small habits keep a fixed insole fresher for much longer.

Air them out properly after every wear

• Leave shoes open to air overnight after taking them off.
  
• Don’t store them immediately in tight lockers, sealed cupboards or gym bags.
  
• If you like, use cedar shoe trees to absorb moisture and help control odour.
  

Trainers benefit especially from being aired out after a workout rather than “maturing” in the boot of the car.

Prevent odour with sprays and powders

There are dedicated shoe sprays and powders available, many based on tea tree, eucalyptus or other natural ingredients. They slow bacterial growth and add a fresher scent.

• Apply only to completely dry insoles.
  
• Use sprays lightly-just enough to slightly mist the surface.
  
• Sprinkle powders in the evening and shake out the excess in the morning.
  

If you have sensitive skin, be cautious with heavily perfumed products and keep an eye on how your feet react.

Shoe rotation, socks & health: what many people overlook

A commonly missed factor is recovery time. If you wear the same pair daily, the insole rarely gets the chance to dry out fully-and bacteria thrive in that warm, damp environment.

A better plan is to rotate at least two pairs; for sports shoes, three is even better. That gives each pair of fixed insoles roughly 24 hours to air out, even when you’re not deep-cleaning every time.

Sock choice matters too. Performance socks made from merino wool or technical fibres move sweat away faster than pure cotton. That reduces moisture load on the insole and helps keep odour under control.

If you regularly suffer from very sweaty feet, or you keep finding signs of fungal infection despite good care, seek medical advice. In those cases, hygiene routines alone are often not enough and the skin may need treatment.

When cleaning is no longer worth it

Every insole eventually reaches the end of its life. Common warning signs include:

• The foam underfoot feels uneven, compressed or crumbly.
  
• Even after a thorough clean, unpleasant odour returns within hours.
  
• The surface shows cracking, deep staining, or areas that are lifting.
  

At that point, it may be time to retire the shoes-especially if the insole is truly integrated and can’t be replaced properly. However, a cobbler or specialist retailer can sometimes assess whether rebuilding the footbed makes sense; with expensive walking shoes or high-quality leather shoes, it can be worth considering.

Spotting these signs early and cleaning fixed insoles gently on a regular basis saves money over time, is kinder to your feet, and makes it far less likely you’ll feel self-conscious about your footwear-whether you’re at the office, the gym or visiting friends.