How to Wash a Wool Blanket Without Shrinking It
Updated July 2026
The short answer
Wool felts (shrinks into dense, matted fabric) when it gets heat and agitation together. A blanket-sized piece of wool is a blanket-sized opportunity for that mistake, which is why the method is: cold water, wool-safe detergent, the gentlest possible handling, and flat drying. No hot water, no normal cycle, no dryer. Machine route: wool or delicate cycle, cold, low spin, wool detergent (only if the label allows machine washing). Hand route (always safe): the bathtub method: soak, press gently, drain, press out water without wringing, and dry flat on towels. Slower, and kinder to a blanket you'd miss.
Before you start
Read the label: "superwash" or machine-washable wool tolerates the machine's wool cycle; anything vintage, hand-loomed, or labeled dry-clean/hand-wash gets the tub or a professional.
You need wool-safe (enzyme-free) detergent; regular detergent's protease enzymes literally digest protein fibers like wool.
Air the blanket and shake it out first; wool self-freshens remarkably, and many "needs washing" blankets really need an afternoon outside. Wash wool rarely; once or twice a season is plenty for a blanket in normal use.
Spot-clean small marks instead of full washes when possible: cold water, a drop of wool detergent, gentle dabbing.
Steps
Machine method (label permitting):
- 1Wool or delicate cycle, cold water, lowest spin, with wool-safe detergent at a small dose.
- 2Wash the blanket alone: it needs the room, and companions add agitation.
- 3Pull it out immediately when the cycle ends and move to drying.
Bathtub method (always safe):
- 1Fill the tub with cold water and a capful of wool detergent, lay the blanket in, and press it under gently.
- 2Soak 15–20 minutes, pressing occasionally. No swirling, no scrubbing.
- 3Drain, refill with cold, and press to rinse; repeat until the water runs clear.
- 4Press the water out against the tub, never wring, then roll sections in dry towels and press again.
Drying, either method:
- 1Dry flat on a rack or clean towels, reshaped to size, away from sun and heat. Rotate and flip daily; a blanket takes a day or three.
- 2Never the dryer. Even air-only tumbling agitates; heat felts. This is the step that ruins wool blankets.
What not to do
- Do not use hot or even warm water: cold only, both washing and rinsing.
- Do not use regular detergent; enzymes eat wool. Wool-safe only.
- Do not wring, twist, or hang a soaked wool blanket; it stretches under its own water weight.
- Do not tumble dry under any setting.
- Do not dry in direct sun or on a radiator; both stiffen and yellow wool.
- Do not wash on a schedule; wool wants airing often and washing rarely.
Frequently asked questions
Can I put a wool blanket in the washing machine?
If the label says machine washable or superwash: yes. Use the wool/delicate cycle, cold, lowest spin, with wool detergent, washed alone. No such label means the bathtub method or a professional. When the label is missing on a blanket you care about, assume hand wash.
How do you dry a wool blanket without stretching it?
Flat, supported everywhere: across a drying rack, over two parallel rails, or on towels on the floor, reshaped to size and flipped daily. Hanging a soaked wool blanket from a line stretches it under its own water weight; press the water out thoroughly first no matter where it dries.
How often should a wool blanket be washed?
Once or twice a season in regular use, and some years never, if it lives over a top sheet. Wool self-freshens with airing: a few hours outside on a dry breezy day resets most blankets better than a risky wash would.
My wool blanket shrank and felted. Can it be saved?
Felting is permanent, honestly. A borderline case may relax slightly with a lukewarm soak in hair conditioner and firm reshaping, but densely felted wool has physically locked its fibers. The traditional consolation: felted wool is durable; a shrunken blanket often retires well as a pet bed or picnic blanket.
Spill on the wool blanket? Spot-treat before committing to a full wash; the Stain Rescue Tool will flag what's wool-safe.
Use the Stain Rescue Tool