Leather Odor, Mold and Mildew: Find the Right Fix for Your Item

Leather mold grows when leather stays damp in still air, so the fix is to dry the item, remove the growth outdoors with a HEPA vacuum and a soft brush, and then lower the humidity where it is kept. Smells are different: the right fix depends on whether the odor comes from mold, smoke, sweat or the tannery. Use the checks below to find the tutorial for your item.

Key takeaways- Moisture is the cause. Without it, the mold spores that are always around stay dormant.- Small patches are a DIY job. Large areas, or anyone with asthma, allergies or a weak immune system, call for someone else.- Some white spots are wax or oil, not mold. A simple swab test tells them apart.- Keep stored leather below 60% relative humidity (RH).

First, a quick safety check

The US EPA says most people can clean a moldy area smaller than about 10 sq ft (roughly 3 ft by 3 ft) themselves. A jacket, a pair of shoes or a bag is usually well under that. A sofa or a closet full of coats may not be.

Stop and get help if anyone doing the work has asthma, a mold allergy, chronic lung disease or a weakened immune system. The Canadian Conservation Institute (CCI) advises those people to stay away from the item and the area.

For everyone else, wear an N-95 respirator, gloves and goggles without vent holes. Work outdoors.

What is on your leather? Mold, mildew or wax bloom

Color depends on the leather: mold shows brown to black on light leather and white or pale on dark leather. If you are unsure, CCI says to treat the item as moldy.

Why leather molds

Leather is a protein material, and the National Park Service (NPS) lists it among the materials most open to mold attack. CCI says an RH above 65% favors mold on leather, and poor air circulation adds to the risk.

Time matters too. CCI gives roughly 2 days to growth at 90-100% RH, 10 days at 80% and 100 days at 70%. That is why a jacket put away damp, or a bag left in a humid closet over summer, comes out fuzzy.

Removing mold and mildew

The conservation method is the same for most items: seal the item in a bag, dry it, then vacuum the dry growth outdoors with a HEPA vacuum and a soft brush. If the mold smears, the leather is still too damp.

Sources disagree about wiping mold with alcohol. A leather-color vendor recommends rubbing alcohol, while a furniture maker says alcohol damages leather's topcoat. The tutorials explain both views.

• How to remove mold from leather: the full step-by-step method for finished (smooth) leather jackets, shoes, bags and furniture.
• How to clean mildew from leather: light surface mildew, suede included.
• How to clean mold off leather: the same job for readers in Australia.
• How to remove mold from a leather coat: linings, collars and long coats.

Getting smells out of leather

New leather often smells of the tanning process. Used leather picks up food, mildew, perfume, sweat and smoke. Each needs its own approach.

Skip ozone generators. The EPA says ozone at safe levels does not remove many odor chemicals or mold, and it can damage fabrics and dyes.

Keep it from coming back

Store leather in a cool, dry, well-ventilated place on a wide hanger, under a breathable cotton cover rather than plastic. A fan helps air move, and silica gel can buffer humidity in a closed box or cabinet. Our leather care and cleaning guide covers routine care, and the suede care guide covers napped leather.

What this site and the store can and can't do

These guides are free how-tos. Leather Collection, the store behind this network, makes leather garments and does not sell cleaning or care products. Any product brand named in our tutorials is there to report what its maker says, not as a recommendation.

For a valuable or sentimental piece, the EPA suggests a specialist restorer, since mold can leave stains.

FAQ

How do I remove white mold from leather?

First check it is mold: wax bloom also looks white. If it is mold, dry the item, then vacuum it outdoors with a HEPA vacuum and a soft brush while wearing a mask, gloves and goggles. The mildew tutorial walks through it.

Is alcohol or vinegar better to kill mold?

Sources disagree, and neither is settled for leather. One vendor prefers alcohol and calls vinegar too acidic; a shoe blog uses diluted vinegar; a furniture maker warns that alcohol harms finishes. Conservation guides rely on drying and vacuuming instead.

Can moldy leather be restored?

It depends on the damage: mold can stain and weaken leather permanently. Some spores stay behind even after cleaning, so fix the damp or it returns.