Circulus was named by Jeffreys (1842) [Sepkoski's age data: T Than-l R Sepkoski's reference number: 794]. It is extant. Its type is Circulus duminyi.

It was reranked as Vitrinella (Circulus) by Maury (1917).

It was assigned to Vitrinella by Maury (1917); to Cyclostrematidae by Harris and Palmer (1947), Gardner (1948); to Adeorbinae by Marquet (1997); to Adeorbiidae by Lozouet (1998); to Vitrinellidae by Gardner (1947), Todd (2001), Wienrich (2001); and to Archaeogastropoda by Sepkoski (2002).