Coleophora argentula is a moth of the Coleophoridae family. It is found in most of Europe, Russia and Asia Minor. It occurs in meadow-steppe and dry meadows. The wingspan is 9.5–13 mm. Adults are on wing in June and July. The larvae feed on Achillea millefolium and Achillea ptarmica. They feed on the flowers and fruit of their host plant. Early instars live within the seedhead. Each forming a silken case. This case is initially white, but becomes brown when fully formed. It reaches a length of about 5–6 mm. Pupation takes place within the case.