Last Updated on October 4, 2026 by Umar Farooq
The short version of how to wash a backpack: empty every pocket, strip anything rigid or removable, seal it in a pillowcase, throw in three or four old towels, and run a gentle cycle with a small amount of mild detergent. Then hang it up to dry, because the dryer is what actually kills backpacks.
Every other page on this subject is written by someone thinking about the bag. This one is written by someone thinking about the drum. A backpack is not laundry — it is a semi-rigid, buckle-covered object with load-bearing straps, and you are about to spin it inside a thin steel basket at a speed luggage was never designed for. The bag will usually survive. Whether the machine does comes down to three precautions the outdoor blogs mention in passing, if at all.
Three things a wet backpack does that laundry does not
A duvet, a pair of jeans and a bath towel all behave the same way in a drum: they soak, they deform, they spread out, and they let the machine do its job. A backpack does none of those things, and understanding why is what turns the mesh-bag advice from a nicety into a rule. It also explains most of the “my washer banged and stopped” reports that follow a backpack wash.
The hardware hits the drum. Sternum clips, hipbelt buckles, ladder-lock adjusters and metal zip pulls are hard points with no give, thrown against stainless steel repeatedly for the length of the cycle. On a front-loader they can also work into the fold of the door gasket, which is the last place you want an abrasive object living (how to clean a washing machine gasket).
Unusually, both sides agree on the fix. Whirlpool, who make the machine, say to “place the backpack inside a pillowcase or laundry bag to prevent straps or zippers from getting tangled or caught inside the washer” (how to wash a backpack in 5 steps). JanSport, who make the bag, describe the same event from the other end: “If a strap gets caught in the washing machine’s agitator, it could stretch, rip, or even break off completely” (how to clean a school backpack). The pillowcase is not protecting the fabric. It is stopping a strap finding something.
It cannot balance. This is the one nobody covers, and it is why the cycle goes wrong. A soaked backpack is a single dense mass with a fixed shape, so wherever it settles is where the weight stays — and a drum with all its mass on one side is the textbook aborted-spin condition. The machine attempts the spin, senses the imbalance, stops, redistributes and tries again, which is why a backpack wash so often runs long or ends with the bag still dripping.
Samsung gives the same instruction for shoes, which are the same problem in a smaller package: use a mesh bag or pillowcase “to prevent them from causing damage to the washing machine tub”, and add “a few towels or other soft items” “to prevent excessive noise and vibration” (wash sneakers in your washer). If the banging has already happened, washing machine shakes during spin covers what the machine is doing about it.
It holds water. Foam back panels, padded straps and doubled fabric hold water a low spin will not pull out, so the bag comes out considerably heavier than it went in and stays damp far longer than laundry would. That is normal for a backpack, not a symptom — but if the towels from the same load come out soaked too, that is a different problem (clothes soaking wet after wash).
Backpacks that must never go in the machine
None of these categories are about how dirty the bag is. They are about whether it contains something that cannot bend.
| Bag type | Machine? | Why |
|---|---|---|
| School bookbag, nylon or canvas | Usually yes | Soft-sided, nothing rigid, no coating to strip |
| Hiking pack with an internal frame | No | Aluminium stays and framesheets do not deform |
| Any leather or suede trim | No | Water marks and stiffens it permanently |
| Anything with a battery or wiring | No | Soaked cells crushed against a drum are a fire risk |
| Wheeled or hard-backed packs | No | A rigid plate concentrates every impact in one spot |
A frame is the clearest case. An aluminium stay is a stiff rod sewn into a sleeve, and because it cannot flex it turns the whole pack into a lever hammering one point of the drum wall instead of a soft mass rolling over. Whirlpool’s own first step is “remove any metal frames and detachable straps and hip belts”. REI go further and rule the machine out entirely for technical packs: “Never wash a pack in a washing machine or dry it in a dryer” (REI, “how to clean a backpack” — its guidance is for hiking packs, not school bags). They are not contradicting Whirlpool. They are describing a different object.
The battery case deserves saying plainly, because charging backpacks are ordinary now and the power bank usually lives in a zipped sleeve people forget exists. A lithium cell that has been soaked and then repeatedly compressed against a drum wall is a genuine fire risk. Check the sleeve, pull the bank and the cable, and check again.
How to wash a backpack in the washing machine, step by step
Read the care label first — it outranks everything below. Whirlpool limit their machine advice to “basic school backpacks and bookbags made of nylon or canvas”, and treat it as a once-or-twice-a-year job rather than routine laundry.
- Empty every pocket and leave every zip open. Water has to reach the inside, and a closed pocket carries a litre of it through the spin.
- Strip everything removable. Hipbelt, sternum strap, rain cover, frame, laptop sleeve, keyrings, clip-on bottles. Wash the straps by hand.
- Shake it out and vacuum the seams. Grit left in the bag ends up in the pump filter.
- Cut any loose threads around the zippers and spot-treat stains with a soft brush first.
- Seal it in a pillowcase or mesh laundry bag, and tie it closed. An open pillowcase lets a strap out, which is the whole failure this step exists to prevent.
- Add three or four old towels. This is the step that makes the load work. Two is not enough for a full-size pack.
- Gentle cycle, mild detergent, lowest spin available. Whirlpool say to “add a small amount of mild detergent (fill to the first line of the detergent cap) and run a gentle cycle”. Skip fabric softener — it coats water-repellent finishes.
Whirlpool’s machine steps do not name a water temperature. Mountain Warehouse’s rucksack guidance does: “Wash the backpack on a gentle cycle in cold water” (Mountain Warehouse, “how to clean a backpack”, read live on 2 September 2026). Cold is the safer default for anything glued, coated or printed, so use it unless the label says otherwise. Do not fill the rest of the drum with a normal wash either — the towels are ballast, not a laundry opportunity (washer load size and how full to fill it).
Drying, which is where backpacks actually die
The dryer is the one thing every manufacturer on this topic agrees about, and they agree because heat destroys the parts of a backpack that water never touches. Whirlpool are blunt: “Never put a backpack or bookbag in the dryer, as the heat can damage the fabric and accessories like zipper pulls.” Adhesives soften, laminates separate, plastic buckles distort, and none of it comes back.
Hang the bag upside down with every pocket open, indoors or in shade rather than direct sun. Give it a full day, then check the padded back panel and the shoulder straps specifically — they dry last, and a bag put away damp comes out of the cupboard smelling worse than it went in.
Is it worth putting it in the machine at all?
For a nylon bookbag, bagged and padded with towels: yes, once or twice a year. For a hiking pack with a frame, a hipbelt and a water-repellent finish: no, and the company that made it will tell you so. The dividing line is not how filthy the bag is. It is whether anything inside it cannot bend — which is the same reasoning that makes washing shoes in a washing machine a bag-and-towels job too.
FAQ
Can you wash a backpack in the washing machine?
Nylon and canvas bookbags, usually yes — bagged, cushioned with towels, on a gentle cycle. Framed hiking packs, leather-trimmed bags and anything with a battery, no. The care label overrules any general rule.
What cycle should I use?
A gentle or delicates cycle with the lowest spin available. Whirlpool specify a gentle cycle and a small amount of mild detergent; Mountain Warehouse add cold water. Spin speed is what turns hardware into an impact problem.
Do I really need a laundry bag or pillowcase?
Yes, and it is the step not to skip. An appliance maker and a bag maker independently describe the same failure — a strap escaping and catching something. The pillowcase is what stops that.
Can I put a backpack in the dryer?
No. Heat damages fabric, coatings, adhesives and zip pulls, and it does not come back. Hang it upside down and give it a day.
My washer banged loudly and stopped mid-cycle. What happened?
The balance system found a load it could not spin. Add towels, spread the bag against the drum wall rather than leaving it in a heap, and restart on a lower spin.
How often should a backpack be washed?
Whirlpool frame it as a deep clean “once or twice a year”. Everything in between is a damp cloth, which is gentler on the bag and involves no drum at all.
