Filament yarn is made by forcing a liquid substance through the spinneret thus making an endless yarn. A smooth spinneret makes the fibre smooth and shiny. Spinnerets with a texture give the yarn a different look, for instance with more volume.

There are filament yarns of a synthetic origin, like polyester and those of a natural origin like viscose or latex
Silk-worms use this method for making their cocoon. Their filament yarn can reach up to 900 metres