Early-life stress alters brain function and increases the risk of suffering psychiatric disorders later in life. Sustained stress affects the response of the mesolimbic dopaminergic (DA) system. That system regulates the activational component of motivated behavior, including effort-based decision-making. The aim of our study was to evaluate the impact of social distancing starting at PND28 (SD - two mice per cage separated by a wall with holes) on the willingness to exert effort during adulthood in an operant procedure. In this task, mice of both sexes were trained in different schedules that required different levels of effort to obtain a preferred drink (10% sucrose solution). Finally, in the Progressive/choice procedure, mice had to choose to work hard to obtain 10%, or freely drink 3% sucrose solution. Additionally, the impact of SD on pharmacological DA manipulations were also evaluated. SD decreased lever pressing in effortful schedules but only in female mice. DA depletion decreased the number of lever presses in mice of both sexes, inducing an anergic pattern. The administration of a DA-uptake-blocker after DA depletion restored the number of lever presses in all groups, but not in SD females. Finally, the preference for interacting with novel conspecifics rather than novel objects was evaluated. SD animals, independently of sex, had a clear increased preference for social interaction compared to non-separated animals. Thus, SD seems to affect social behavior in both sexes, although only females showed an anergic pattern and seem to be more vulnerable to DA manipulations.