How to Wash a Christmas Jumper Without Ruining It

A Christmas jumper survives one thing badly: the wash after the party. Gravy, mulled wine, a battery pack nobody remembered to remove — the jumper usually makes it through December and then dies in a machine in January.

Most of this is avoidable, and the rules differ sharply depending on what you own.

First: work out what it actually is

Knitted, printed, light-up and sequinned jumpers each fail in a different way, so the single most useful thing is knowing which you have. If you are unsure, knitted or printed covers how to tell at a glance.

Knitted acrylic jumpers

Acrylic is hard-wearing and takes machine washing better than wool. Its weakness is heat and weight.

Wash cool — 30 degrees, gentle cycle. Heat is what makes acrylic go hard and slightly shiny, and that change is permanent.
Never tumble dry. This is the one that actually destroys them.
Dry flat, not on a hanger. A wet knit is heavy and will stretch at the shoulders under its own weight, giving you the drooping-shoulder look that no amount of washing reverses.
Turn it inside out to protect any raised pattern.

One environmental note worth knowing: research at the University of Plymouth found acrylic sheds close to 730,000 microfibres in a single wash — more than polyester or a poly-cotton blend. Washing less often, on a full load and at a lower temperature, genuinely reduces that. A jumper worn for an evening rarely needs washing at all; airing it usually does the job.

Source: CNN, reporting Hubbub and University of Plymouth research

Printed sweatshirts

These are the easiest to wash and the easiest to ruin, because the print is the entire product and it sits on the surface.

Inside out, every time. This is the whole trick. The print then rubs against itself rather than against the drum.
Cool wash, low spin.
Never iron the print. If you must iron, do it inside out and avoid the design entirely.
Air dry. Tumble drying is what makes all-over prints crack at the shoulders first, where the fabric moves most.

Light-up jumpers

This is where the genuine disasters happen, and there is really only one rule.

Take the battery pack out before it goes anywhere near water. On almost every light-up jumper the pack unclips from a small pocket in the lining, usually near the hem. Find it when the jumper arrives, not when you are loading the machine at eleven at night.

Check whether the light unit itself detaches, or only the batteries. If the wiring is sewn in, the jumper is hand wash only regardless of what the label suggests.
Remove the batteries entirely if you are putting it away until next year — cells left in a pack for eleven months leak and corrode the contacts.
Never tumble dry a jumper with wiring in it, under any circumstances.
Dry it completely before storing. Damp plus electronics is how a working jumper becomes a broken one over the summer.

The rest of the light-up failure modes are covered in six things that go wrong with light-up Christmas jumpers.

Sequins and glitter

Sequinned jumpers look superb under evening lighting and are the least durable thing in the category. Treat them as occasion wear.

Hand wash if you can face it. Cold water, gentle detergent, no wringing.
If it goes in the machine: inside out, in a mesh laundry bag, on the most delicate cycle available.
Dry flat and away from radiators. Heat warps the sequins themselves.
Store folded rather than hung — hanging drags on the stitching that holds each sequin.

The party stains, specifically

Red wine. Blot, do not rub. Cold water from the back of the fabric, pushing the stain out rather than through. Heat sets it permanently, so no hot water and no dryer until it has gone.
Gravy and grease. Let it dry, scrape off what lifts, then a little washing-up liquid worked in gently before a cool wash.
Candle wax. Harden it with something cold from the freezer, crack it off, then lift the residue with a warm iron through brown paper — on plain knit only, never over a print.
Anything glittery from a cracker. Sticky tape before washing. It will otherwise redistribute itself across every other item in the machine.

Putting it away in January

Clean, completely dry, batteries out, folded rather than hung, and somewhere that is not the loft if you can manage it — temperature swings and damp are what ruin stored knitwear.

Do that once and a good knitted jumper will still be doing the job in ten years, which is the entire argument for buying one properly in the first place.