How to Wash a Duvet at Home

⚠

Completely dry before use. Damp filling grows mould within 1–2 days. Squeeze the filling through the cover in multiple spots — any cool or damp area means more drying time needed.

Machine Capacity Check — Do This First

The biggest obstacle to home duvet washing is machine capacity. A compressed duvet forced into a too-small drum will not wash properly — the water and detergent cannot penetrate fully, the duvet gets unevenly wet, and the filling clumps permanently. As a guide: a single duvet (4.5–7 tog) typically needs a 7kg drum. A double duvet (10–13.5 tog) needs a 9–10kg drum minimum. A king-size duvet often needs a 10–12kg drum. Many standard home washing machines have a 7–8kg drum — fine for single duvets but often too small for a double or larger. The test: try to push the duvet into the drum. If it is fully compressed and there is no free space for it to move, it is too large for that machine. A launderette or communal laundry with a 12–15kg capacity machine is the correct solution for large duvets.

Synthetic Duvet — Step by Step

Check the care label

Most synthetic (hollowfibre, microfibre, polyester) duvets are machine washable. The care label will show the maximum washing temperature. Many can be washed at 60°C, which kills dust mites. Check before assuming.

Verify machine capacity (see above)

A squashed duvet in an undersized drum will not wash effectively. The duvet must have room to move in the drum. If in doubt, use a launderette.

No detergent drawer — add liquid detergent directly to the drum

Place the duvet in the drum. Add a half-dose of liquid detergent directly into the drum alongside the duvet — not in the detergent drawer. Powder detergent at the drawer can leave residue when the duvet absorbs so much water that flow through the drawer is restricted.

Wash at 60°C (or 40°C for colour or delicate label)

60°C kills dust mites — the most hygienically effective temperature for bedding. Synthetic fibre duvets typically tolerate 60°C. Check the label — some microfibre duvets specify 40°C maximum. Run a full cycle including spin.

Tumble dry low with dryer balls — or air dry completely

Place the duvet in a large-capacity tumble dryer with 2–3 dryer balls or clean tennis balls. The balls keep the filling moving, preventing it from clumping and felting together. Run on low heat for 1.5–3 hours. Check midway and pull apart any clumps by hand before returning to the dryer. Critical: the duvet must be completely dry on the inside before use. Squeeze the filling through the fabric — if any part feels damp or cold, dry for longer. Incomplete drying allows mould to grow inside the filling.

Check for mould before putting on the bed

After drying, press the filling in different sections and smell. Damp smell = not dry enough. Mould smell = mould has started growing inside. If mould is detected, wash again immediately with a cup of white vinegar added to the drum, then dry fully.

Down Duvet — Step by Step

30–40°C only — see also: How to wash down

Check the fill weight and machine capacity

Down duvets are significantly heavier when wet than synthetic ones. A 4.5 tog double down duvet absorbs a large amount of water and becomes very heavy — this matters for machine drum size and for the dryer capacity.

Wash at 30–40°C with a down-safe or gentle liquid detergent

Down needs gentle washing. Use a low temperature (30–40°C) and a delicates or down-specific detergent (Nikwax Down Wash, Grangers Down Wash). Biological detergent can degrade the natural proteins in down feathers over repeated washes. No fabric softener — it clogs the down clusters and reduces loft.

Rinse twice

Down requires thorough rinsing to remove detergent residue, which reduces loft significantly. Run an extra rinse cycle.

Tumble dry LOW with 2–3 tennis balls — long cycle

Down takes significantly longer to dry than synthetic filling. Expect 2–4+ hours in a large-capacity tumble dryer on LOW heat. Tennis balls are essential for down — they break up the clumped wet clusters that prevent drying and restore loft. Check every 30–40 minutes: remove the duvet, shake vigorously by hand, and pull apart any large damp clumps before returning to the dryer. The duvet will feel compressed and flat when wet — it should expand back to its original loft when fully dry.

Air dry finish in a ventilated space

After tumble drying, lay the duvet flat in a well-ventilated room for 4–6 additional hours to ensure complete drying through to the centre. Down retains moisture at the core of the clusters long after the surface feels dry.

By Duvet Type

Synthetic hollowfibre / polyester

Every 6–12 months

Most forgiving. Machine wash 40–60°C in a large drum. Low tumble dry with dryer balls. Very common, affordable, and durable.

Microfibre

Every 6–12 months

Similar to hollowfibre. Check the label — some specify 40°C maximum due to finer fibre structure. Gentle cycle may be recommended.

Down (feather and down mix)

Every 2–3 years (with regular airing)

Requires careful gentle washing. 30–40°C. Down-safe detergent. Extended drying with tennis balls. See the separate down washing guide for full detail.

Wool-filled duvet

Every 1–2 years

Check the label carefully — some wool duvets are hand-wash or dry-clean only. If machine washable: 30–40°C, wool cycle, gentle spin. Lay flat to dry — never tumble dry.

Silk-filled duvet

Every 1–2 years

Usually dry clean only or very gentle cold hand wash. The silk filling can be damaged by agitation. Follow the care label — if it says dry clean, use a professional.

Anti-allergy synthetic

Every 3–6 months

Designed for allergy sufferers — wash more frequently. 60°C kills dust mites. Same washing process as standard synthetic.

How Often to Wash

Most duvets should be washed every 6–12 months. Duvets used without a duvet cover: every 3–6 months. Anti-allergy duvets for dust mite sufferers: every 3–6 months at 60°C. Down duvets: every 1–3 years if cared for properly and regularly aired (down is a natural temperature-regulating material that benefits from regular outdoor airing rather than frequent washing). Between washes, air the duvet outside for a few hours regularly — this reduces moisture buildup and freshens the filling without washing stress.

What to Avoid

Machine too small for the duvet

A compressed duvet washes unevenly and the filling may clump permanently. Use a launderette for oversized duvets.

Incomplete drying

This is the most common and most serious mistake. Even a slightly damp core grows mould inside the filling within 1–2 days. Mould inside a duvet is almost impossible to remove without professional treatment. Dry until completely dry on the inside.

High heat for down

High heat melts the protein structure of down feathers, permanently reducing loft and insulating properties. Low heat only for down.

Fabric softener

Coats down clusters and synthetic fibres with a film that reduces loft (for down) or blocks the moisture-wicking properties of synthetic filling.

Powder detergent

At the reduced water flow through an overstuffed drum, powder often fails to dissolve fully and leaves residue in the filling. Liquid detergent added directly to the drum is more reliable.

FAQ

Can you wash a duvet in a washing machine?

Yes, if your machine is large enough. A double duvet typically needs a 9–10kg drum capacity; a king duvet needs 10–12kg. If the duvet fills the drum completely with no room to move, it will not wash properly. Launderettes with 12–15kg commercial machines are the right choice for large duvets. Most synthetic duvets can be washed at 60°C; down duvets need 30–40°C.

How do you dry a duvet at home?

Place in a large-capacity tumble dryer with 2–3 dryer balls or clean tennis balls. Set to low heat. Run for 1.5–4 hours (down takes longer than synthetic). Check every 30–40 minutes — remove, shake, pull apart clumps, return to dryer. The most important rule: ensure the filling is completely dry on the inside before use. Squeeze the filling through the cover — if any part feels damp or cold, dry for longer. Incomplete drying leads to mould growing inside the duvet.

How often should you wash a duvet?

Synthetic duvets: every 6–12 months. Anti-allergy duvets: every 3–6 months at 60°C. Down duvets: every 1–3 years if regularly aired (outdoor airing every few months reduces the need for washing). Regular washing stresses the filling — air regularly between washes and use a duvet cover that is washed every 2–4 weeks.

How do you get mould smell out of a duvet?

If mould smell develops inside a duvet, wash immediately with a cup of white vinegar added directly to the drum alongside the duvet. Use a 60°C cycle if the filling tolerates it (synthetic: yes; down: 30–40°C maximum). Then dry completely, pressing the filling in all sections to confirm no damp areas remain. If the mould smell persists after two washes, the filling may be too deeply contaminated — professional cleaning or replacement may be needed.

Got a stain on bedding?

Use the stain picker →