A Down Duvet is generally considered to be the best you can get. Down is the collective name for the small, light and very warm feathers that come from the breast of duck, geese and other water fowl. They usually form a layer underneath exterior feathers which are tougher and coarser. As well as insulating the birds against heat loss they also help the birds to float, in part because they trap many small pockets of air.

The two main sources of down feathers are ducks and geese. For many farmers, the down is a by-product of breeding birds to eat. There have been some cases of inhumane treatment against birds involving plucking down and feathers whilst they are still alive. After public concern, IKEA was forced to change the way that it sourced down from suppliers to stop this happening.

Whilst geese are vegetarian, ducks eat a variety of different food and this can give duck feathers an unusual smell. Also in favour of goose down is that the bird produces more down (so they should be less small feathers mixed in) and the down produces a warmer filling for duvets.

The down used in making fillings for duvets is typically sources from the following parts of the World: Asia, Europe (particularly Hungary) and Siberia. Down from Siberia is warmer than others and generally considered to be the best quality. This also makes it the most expensive to buy.

Down duvets are considered the best for their combination of warmth and light weight. This gives the sleeper optimal conditions for sleeping and as it is also a natural material allows the skin to breathe easily.