To wash a backpack, empty it, brush out the debris, then hand-wash it in a bath or large sink with lukewarm water, a pH-neutral or technical soap and a soft brush, rinse it thoroughly and hang it upside down with every zip open to air-dry away from sun and heat. Do not put a trekking rucksack in the washing machine or tumble dryer: Osprey, Deuter and Gregory all advise against it because it can damage the frame, padding and waterproof coatings.
Below you will find when a quick spot clean is enough, how to deep-clean step by step, how to treat shoulder straps and hip belts, how to tackle mould and smells, how to re-proof, and how to store a pack so it lasts for years.
Quick answer: how to clean a backpack
| Situation | What to do | Time |
|---|---|---|
| After every trip | Empty, shake out, vacuum seams, wipe inside and out with a damp sponge, air-dry open | 10–15 minutes |
| Small stain or mark | Spot clean with lukewarm water, mild soap and a soft brush; rinse the area | 5–10 minutes |
| Sweaty straps, muddy base, smells | Full hand-wash in a bath or sink, thorough rinse, hang to dry | About an hour, plus 1–2 days drying |
| Water soaks into fabric instead of beading | Wash, then apply a spray-on DWR re-proofer | Plus drying time |
| Mould spots | Hand-wash, gently treat affected areas, dry thoroughly in a ventilated space | Varies |
Why you should not machine-wash or tumble-dry a rucksack
A trekking pack is not just fabric. It has a frame sheet or alloy stays, foam in the hip belt and shoulder straps, a polyurethane (PU) coating on the inside of the fabric that makes it water-resistant, and a DWR finish on the outside. A washing machine twists and pummels all of these at once.
- Deuter says to never wash a backpack in a washing machine, as agitation stresses the material and coating, and that machine washing or tumble drying will damage the PU coating.
- Osprey advises against machine washing because it can harm the pack’s structure and fabric.
- Gregory says not to use a washing machine, detergents or solvents, and warns against dryers, hair dryers and heat guns, which damage the protective coatings.
A machine can also damage the drum: buckles and frame stays bang around inside it. Small, unstructured daypacks may carry a label allowing a gentle machine wash, and if yours does, follow it. For any framed trekking pack, wash by hand.
What you need
- A bath, shower tray or large sink.
- Lukewarm water (around 30°C is a good upper limit).
- A mild, pH-neutral soap or a technical gear wash. Avoid biological detergents, bleach and fabric softener.
- A soft brush or sponge, and an old toothbrush for zips and seams.
- A vacuum cleaner with a nozzle attachment (optional).
- Towels for blotting.
- A spray-on DWR re-proofer if the fabric no longer beads water.
How to spot clean a backpack
For a light refresh or a single mark, spot cleaning avoids soaking the foam and back system.
- Empty every pocket and shake the pack upside down.
- Vacuum the inside seams and the base, where grit collects.
- Dip a soft brush or sponge in lukewarm water with a little mild soap and work the mark gently. Gregory warns that excessive brushing can damage the fabric’s protective coatings, so be gentle.
- Wipe the area with a clean, damp cloth to remove soap.
- Leave the pack open to air-dry.
How to hand-wash a backpack step by step
1. Empty and prepare the pack
Empty every pocket, including the hip-belt and lid pockets, and check for forgotten food, sun cream or a leaking bottle. Shake out crumbs and grit and vacuum the seams. Remove the hydration bladder, any rain cover and items that are designed to come off, such as a detachable lid or daypack.
2. Check the care label and the frame
Makers differ on removable parts. Osprey suggests removing the harness and hip belt where they are designed to come off, so they can be washed and dried separately. Deuter, by contrast, says not to remove the frame or rods, because its back systems are not designed to be taken out and refitted and doing so can cause damage. The safe rule: remove only parts your pack’s manual says are removable. Leave internal frames and stays in place.
3. Wash in lukewarm water
Fill the bath with a few centimetres of lukewarm water and a small amount of soap or gear wash. Lay the pack in it and scrub the inside and outside gently with a soft brush or sponge. Concentrate on the base, which picks up mud, and on high-contact areas.
Do not leave the pack submerged for long, and do not submerge the rain cover, which Deuter says can have its colours run even at hand-washing temperature; wipe it with a damp cloth instead.
4. Clean the shoulder straps, hip belt and back panel
Sweat leaves salt in the foam and mesh, which stiffens the fabric, smells and can irritate skin. Deuter recommends squeezing soapy water through the padding by hand to remove salt deposits. Work the soap into the mesh with a soft brush, then squeeze clean water through repeatedly until it runs clear. This is the part that most often smells, so take your time.
5. Clean zips and buckles
Brush grit out of zip teeth with an old toothbrush and rinse buckles under running water, as Gregory recommends. Sand and dust in zips are the main reason they fail on a trek. Work each zip open and closed while rinsing. Once dry, a zip lubricant can help stiff zips run smoothly.
6. Rinse thoroughly
Drain the bath and rinse the pack with clean, cool water inside and out until no suds remain. Leftover soap attracts dirt, can affect water repellency and, on the shoulder straps, can irritate skin.
7. Blot and dry
Press out excess water with towels; do not wring the pack, which can crease the frame sheet and padding. Then dry it as described below.
How to dry a backpack properly
- Open every zip, pocket and drawcord.
- Hang the pack upside down, or lay it flat, so water drains out of the base and pockets.
- Choose a dry, well-ventilated place out of direct sunlight. UV degrades nylon and coatings over time.
- Keep it away from radiators, heaters, fires and hair dryers.
- Allow time: thick hip belts and back panels can take a day or two to dry completely.
- Do not store the pack until every part, including foam padding, is dry. Damp foam is where mould starts.
Mould and odours
Mould grows on packs stored damp, often in a loft, garage or car boot. Prevention is easy: dry the pack fully after every trip, including after rain, and store it in a dry cupboard.
If mould has already appeared:
- Take the pack outside and brush off loose mould with a soft brush (wear a mask if you are sensitive to mould spores).
- Hand-wash as above, working the affected areas gently with soap and a soft brush.
- Dry thoroughly in a well-ventilated space out of direct sun.
- Avoid bleach and other harsh chemicals, which Osprey and Gregory advise against and which can weaken fabric and coatings.
Mould often leaves a stain even after it is gone. If the PU coating inside has started to flake, peel or smell of vinegar, that is coating breakdown (hydrolysis) rather than dirt, and washing will not reverse it. Contact the manufacturer; Osprey, Deuter and Gregory all run repair and warranty services.
For ordinary sweaty smells, a technical gear wash and a thorough soak of the straps and back panel usually solves the problem. Odour-neutralising products made for outdoor kit are an option; avoid scented household sprays, which only mask the smell.
Re-proofing your backpack
Most pack fabrics have a DWR (durable water repellent) finish that makes rain bead and roll off. Deuter suggests a simple test: drop water on the fabric. If it soaks in rather than beading, the pack needs re-proofing.
- Wash the pack first; proofers bond poorly to dirty fabric.
- Apply a spray-on DWR product for fabrics and gear to the outside, following the label. Osprey suggests a spray-on product for UV and water resistance after cleaning.
- Avoid spraying the shoulder straps and back panel; Deuter notes waterproofing agents can irritate skin where they touch.
- Let it dry as directed.
Remember that no rucksack is fully waterproof. Seams and zips let water in during sustained rain, so use a rain cover and pack sleeping bags and clothes in dry bags. That matters a great deal on monsoon-season treks such as Annapurna Base Camp, where rain can be daily.
How to store a backpack
- Make sure it is completely dry and empty.
- Store it somewhere cool and dry, out of sunlight. Avoid damp basements, garages and lofts that get hot in summer.
- Loosen compression straps and fasten buckles so they do not get crushed or snagged, as Deuter recommends.
- Hang it or store it upright with plenty of space, rather than squashed under heavy items, so the foam keeps its shape.
- Do not store it in a sealed plastic bag.
How often should you wash a backpack?
| Task | How often |
|---|---|
| Empty, shake out and air-dry | After every trip |
| Wipe down inside and out | After every trip, as Gregory recommends |
| Spot clean | As needed |
| Full hand-wash | After a long or very muddy trek, when straps smell, or once or twice a year with regular use |
| Re-proof | When water stops beading, usually after a thorough wash |
Do not over-wash. Every full wash puts some wear on coatings, so a wipe after each trip and a proper wash only when needed is the right balance.
Cleaning your pack before flying home
If you are travelling to Australia or New Zealand after a trek, your pack counts as outdoor equipment. Australia’s biosecurity guidance names camping gear, including backpacks, as potentially risky if it has been used in rural areas, and New Zealand treats used hiking equipment as a risk item to declare. Brush and wipe the base and straps clean of soil and seeds, empty pockets of any food or plant material, and declare the gear on arrival. Our guide to cleaning trekking boots covers the rules in more detail.
Next steps
A clean, well-maintained pack carries better and lasts far longer. If yours is past saving, our guide on how to choose a backpack for trekking explains sizing and fit. While you are cleaning kit, also see how to clean water bottles and hydration bladders.
Planning to put your pack to use? Our trek packing checklist and Everest Base Camp packing list show what to carry, and our Everest Base Camp trek and Annapurna Base Camp trek are good places to start. For other routes, see plan your trip.
Frequently asked questions
Can I put my backpack in the washing machine?
Not a framed trekking rucksack. Osprey, Deuter and Gregory all advise against machine washing because it can damage the frame, padding and the PU coating that makes the fabric water-resistant. Some small, unstructured daypacks allow a gentle machine wash; check the label.
Can you tumble dry a backpack?
No. Deuter says tumble drying damages the PU coating, and Gregory warns against dryers, hair dryers and heat guns. Hang the pack upside down with zips open in a well-ventilated place, out of direct sun and away from heaters.
What soap should I use to wash a backpack?
A mild, pH-neutral soap or a technical gear wash. Deuter suggests pH-neutral soap, and Osprey recommends mild soap and warm water. Avoid biological detergents, bleach, solvents and fabric softener, and rinse thoroughly so no residue is left.
How do I get the smell out of my backpack straps?
Squeeze lukewarm soapy water through the shoulder straps, hip belt and back panel padding repeatedly, then rinse until the water runs clear. This removes salt and sweat that cause odour. Dry the pack completely before storing it.
How do I remove mould from a backpack?
Brush off loose mould outdoors, hand-wash the pack with mild soap and lukewarm water, scrub affected areas gently and dry it thoroughly in a ventilated place. Avoid bleach. Mould can leave a stain, and if the inner coating is flaking or sticky, contact the manufacturer.
Should I remove the frame before washing my backpack?
Only if your pack’s manual says it is designed to be removed. Deuter advises against removing frames or rods because its back systems are not designed to be taken out and refitted. Detachable hip belts and harnesses can be removed if the maker allows it.
How long does a backpack take to dry?
Usually one to two days, depending on the thickness of the padding and the airflow. Hang it upside down with every zip open and do not store it until the foam in the straps and hip belt is completely dry.
How do I waterproof my backpack again?
Wash it first, then apply a spray-on DWR re-proofer for fabrics and gear to the outside, avoiding the shoulder straps and back panel. Re-proof when water soaks in instead of beading. Use a rain cover and dry bags too, as no rucksack is fully waterproof.
