Assemblages composed of Heleobia parchappii and H. australis constitute the dominant elements in Quaternary deposits of the Pampean Region in the province of Buenos Aires. This study describes and analyzes the degree of preservation of shells of both species recovered from nine Holocene localities in order to describe and quantify taphonomic alterations, evaluate if preservation varied during the Holocene, and assess their utility as paleoenvironmental bioindicators. Heleobia parchappii displayed better overall preservation than H. australis, with little evidence of fragmentation, limited principally to levels with highest densities. On a temporal scale, no significant differences in fragmentation were found, whereas corrasion and luster displayed temporal differences.