Motility (sometimes referred to as ‘mobility capital’ or ‘mobility potential’) is a still understudied and underutilised concept in both migration and sociolinguistic literature. Perhaps even more than actual mobility, it can shed an important light on the possible connection between language and migration. This theoretical article argues that motility can both be a potential catalyst for language shift, but can in other instances also contribute to language maintenance. Inspired by Fishman’s Graded Intergenerational Disruption Scale (GIDS) and Simon and Lewis’ Expanded Graded Intergenerational Scale (EGIDS), it is assumed that the most important factor in processes of language shift is the attitude of parents, in particular their willingness to transmit their heritage language to their children. This willingness is connected with the perception of the value of the heritage language, which might be, in addition to other factors, influenced by the mobility capital the heritage language might give future generations. The interplay between migrant networks in different countries and the country of origin is key in understanding the parents’ decision-making process. Furthermore, the three main features of motility (access, competence and appropriation) fit quite logically in the already existing EGIDS scale. This article thus argues that motility is a valuable and necessary concept for sociolinguistic research and migration scholars alike.