How to Clean UGG Boots and Sheepskin Boots
Suede outside, wool shearling inside — two materials that both hate machine washing. Suede nap mats permanently when soaked. Wool shearling felts irreversibly. Never submerge. Spot clean, dampen evenly, air dry away from heat.
The Chemistry
Sheepskin boots (UGG and similar styles) are a composite product with radically different material properties on the outside and inside. The exterior is sheepskin suede — the inner surface of a sheepskin hide that has been buffed to raise a nap of short leather fibres. Unlike smooth (full-grain) leather, suede has a disrupted fibrous surface that is highly susceptible to water damage. When suede gets wet, capillary action draws water between the collagen fibres of the nap. As the water evaporates, it moves from the wetter to drier areas of the leather, carrying dissolved salts and tannins with it. These dissolved compounds concentrate at the waterline as the water evaporates, creating the characteristic tide marks on suede. The nap fibres also clump together when wet — the moisture causes the collagen fibrils to bond at contact points. Rapid drying in heat causes irreversible fibre bonding and permanent nap matting. The interior is wool shearling — the wool fleece left attached to the hide. Wool contains lanolin, a complex mixture of esters, fatty alcohols, and fatty acids secreted by the sebaceous glands of the sheep. Lanolin is hydrophobic and provides natural water resistance, heat retention, and antimicrobial properties to the boot interior. Enzyme detergents (proteases) attack the keratin protein of wool, and hot water causes the wool scales to lift and interlock, leading to felting. Lanolin is stripped by surfactants, especially in warm water. A wool shearling interior that has had its lanolin stripped becomes more hydrophilic, less insulating, and more susceptible to odour-causing bacterial growth. The sole is bonded to the upper with adhesive. Sheepskin boots are not waterproof — they are designed for indoor and dry outdoor use. Submersion (including machine washing) forces water between the sole and upper at the adhesive line, weakening the bond progressively. Many sheepskin boots delaminate at the sole after even one machine wash. Salt staining is the main enemy of sheepskin boots in winter. Road salt (calcium chloride or sodium chloride) deposits create white tide marks that become very hard to remove if allowed to dry and set. Treatment must begin with water to redissolve the salt before it bonds permanently to the suede. Suede protector spray applies a fluoropolymer coating to the surface of the suede. The fluoropolymer makes the surface hydrophobic without filling or matting the nap — water beads off rather than being absorbed. This significantly slows salt and water staining and should be applied to new boots before first wear.
Step-by-step
- 1
Dry brush with a suede brush before any moisture
Use a rubber-tipped or wire suede brush to remove loose dirt, mud, and dried surface debris. Brush in one direction along the nap. Never apply any moisture to the boot until loose dirt is removed — wet mud smears into the suede fibres and is much harder to remove.
- 2
Lightly dampen the entire boot — not just the stained area
Using a clean cloth barely damp with cold water, lightly dampen the entire outer surface of the boot evenly. This step is critical — if only the stain is dampened, water will evaporate unevenly from the rest of the boot and create a new tide mark around the wet area. Even dampening prevents tide marks by ensuring the whole surface dries at the same rate.
- 3
Clean with a suede cleaner or a tiny amount of mild soap
Apply a small amount of suede-specific cleaner to a soft cloth and gently work into the stained area using circular motions. For mild dirt, a drop of dish soap highly diluted in water works — no enzyme detergents. Never apply cleaning product directly to the suede. Never scrub aggressively — this permanently mats the nap.
- 4
For salt stains: dissolve with water before they set
Salt tide marks must be treated while still damp if possible. Dampen the affected area with a cloth dipped in cold water and gently blot — do not scrub. The water re-dissolves the salt and the cloth wicks it out. Dried and set salt stains require a 1:1 mix of white vinegar and water — the acetic acid dissolves calcium and sodium chloride salt crystals.
- 5
Stuff and air dry away from any heat source
Stuff the boots with newspaper or a boot shaper to maintain the shape as they dry. Dry at room temperature in a well-ventilated area, away from radiators, heaters, and direct sunlight. Heat desiccates the collagen fibres and causes permanent cracking and nap matting. Drying time is typically 24–48 hours.
- 6
Restore nap with a suede brush when completely dry
Once completely dry, use a suede brush to restore the nap. Brush firmly in one direction to lift the flattened fibres. For badly matted areas, a suede eraser can gently abrade the surface to free compacted fibres. Finish with a coat of suede protector spray to restore the fluoropolymer water-resistant layer.
Issue guide
| Issue | Cause | Treatment | Prevention |
|---|---|---|---|
| Salt tide marks | Road salt (NaCl/CaCl₂) crystallises on suede as water evaporates | Dampen evenly + cold water blot while fresh; vinegar solution for dried marks | Suede protector spray before winter wear; clean within 24 hours of exposure |
| Water staining (tide marks) | Uneven drying concentrates tannins and dissolved compounds at the waterline | Dampen entire boot evenly and allow to dry uniformly | Even dampening technique; suede protector spray |
| Nap matting | Collagen fibres bond when wet and dry flat under pressure | Suede brush when fully dry; suede eraser for compacted areas | Never dry near heat; stuff with newspaper during drying |
| Shearling interior odour | Bacteria metabolise sweat deposits; lanolin stripped by regular detergent | Baking soda inside overnight to adsorb odour; air in sunlight (UV kills bacteria) | Wear socks; allow to dry fully between wears |
| Sole delamination | Water penetrates adhesive bond line when submerged | Resole with suede/leather boot adhesive; press firmly and allow to cure | Never submerge or machine wash; protect sole edge with sealant |
| Shearling felting | Wool fibre scale interlocking from hot water + agitation | Irreversible — once felted, the texture cannot be restored | Never machine wash; no warm water; no enzyme detergent on interior |
Frequently asked questions
Can you put UGG boots in the washing machine?
No. Machine washing sheepskin boots causes multiple irreversible problems: the suede nap mats permanently, the wool shearling felts (shrinks and clumps irreversibly from hot water + agitation), the lanolin in the wool is stripped by detergent, and the sole adhesive bond separates from water penetration. UGG boots must be spot cleaned by hand only.
How do you remove salt stains from UGG boots?
Act quickly — salt stains are much easier to remove while still fresh. Lightly dampen the entire boot surface with cold water first (not just the stain — this prevents new tide marks). Blot the stained area with a cloth dipped in cold water. For dried salt stains, mix equal parts white vinegar and cold water — the acetic acid dissolves the calcium and sodium chloride crystals. Apply, blot, rinse with damp cloth, air dry stuffed with newspaper away from heat.
How do you clean the inside of sheepskin boots?
For odour: sprinkle baking soda inside and leave overnight — baking soda adsorbs VOCs without damaging the wool. For stains: a barely damp cloth with a drop of mild woolite-type detergent, blotted gently. Allow to dry completely with boots upside down. Never wet the interior heavily — the wool can take days to dry and mould can grow inside. Direct sunlight is helpful for UV bacterial kill.
How do you waterproof UGG boots?
Apply a fluoropolymer suede and nubuck protector spray to clean, dry boots. Hold 15–20cm away and apply an even coat. Allow to dry fully (1–2 hours) before wearing. The fluoropolymer creates a hydrophobic layer that makes water bead off rather than absorb into the suede. Reapply every season or after cleaning, as cleaning removes the coating.