BACKGROUND: Avolition is associated cross-diagnostically with extensive functional impairment. Participants with schizophrenia and bipolar disorder (BD) engage in fewer productive activities than healthy controls, with more sedentary activities such as sitting. We examined the temporal variability in activities of participants with schizophrenia and bipolar disorder, focusing on persistence of activities and the likelihood of performing more than one activity at a time. METHODS: 101 participants with schizophrenia and 76 participants with BD were sampled 3 times per day for 30 days utilizing Ecological Momentary Assessment surveys. Each survey queried current activities along with questions about who they were with and if they were home or away and moods. We separated activities into productive, unproductive, or passive recreational categories. RESULTS: Participants with schizophrenia and bipolar disorder reported one activity on most surveys, with that activity commonly being passive or unproductive. No participant reported engaging in more than one productive activity. Productive activities were more likely to occur away from home, with 17 % of surveys from home reporting productive activities. All three activities were persistent, but passive and unproductive activities were more likely than productive activities to be persistent at home. Negative mood states predicted unproductive and passive activities in BD participants only. DISCUSSION: The low numbers of activities, combined with persistence of unproductive and passive activities highlights the impact of avolition. Most persistent activities reflected sedentary behavior. People with schizophrenia or bipolar disorder may benefit from interventions targeting leaving home more often to improve their general levels of functioning and overall health.