Both inert and calculatively committed customers express somewhat similar behaviours that include repeat purchasing despite having negative perceptions and associating in opportunistic behaviours. These characteristics have however resulted in some researchers conceptualising interchangeably the related yet distinct constructs. This paper aims to extend the knowledge on inertia and calculative commitment by examining the extent to which they are distinct. An analysis of data collected online from 376 businesses using a key informant approach indicate that these two constructs demonstrate discriminant validity. Whilst switching costs impact both inertia and calculative commitment, they have differential effects. The implications of these findings are discussed.