Pachychilidae, common name pachychilids, is a taxonomic family of freshwater snails, gastropod molluscs in the clade Sorbeoconcha.

All species in the family inhabit freshwater except Faunus ater, which is a brackish water snail found in estuaries and other coastal habitats.

Most 20th-century authors did not recognize Pachychilidae as an independent family, but affiliated species under different groups, such as Thiaridae and Pleuroceridae.

However, recent revisions based on molecular and morphological evidence have proven their independent and distinct status from the former.

[9] Genera within the family Pachychilidae include: A cladogram based on sequences of mitochondrial 16S ribosomal RNA sequences showing phylogenic relations of Pachychilidae:[12] Faunus ater Potadoma freethi Doryssa consolidata Sulcospira hainanensis Sulcospira testudinaria Sulcospira housei Brotia pagodula Brotia sumatrensis Paracrostoma martini Paracrostoma tigrina Pseudopotamis supralirata Pseudopotamis semoni Tylomelania perfecta Tylomelania neritiformis Jagora dactylus Jagora asperata Pachychilus indiorum Pachychilus conicus Madagasikara madagascariensis Madagasikara spinosa Madagasikara zazavavindrano Madagasikara vazimba Madagasikara vivipara