The aim of this study was to assess the subjective instrumentality and immediate process benefits afforded by regenerative, productive, and consumptive activities and thus to extend the microeconomic perspective on time use. Method: For six consecutive days, 33 women and 48 men aged between 72 and 97 provided signal-contingent self-reports on everyday activities, the reasons for performing them, their contexts and concurrent affect. Results: The dominant reason given for performing productive activities reflected Reid's (1934) third-party criterion. With aggregated data, we found consumptive activities to be associated with higher positive affect. This finding was not corroborated on the occasion level, where social context (in company vs. alone) rather than activity type had a reliable effect on positive affect in situ. The main effect was a function of the individual level of neuroticism, and the association between social context and positive affect was a function of the proportion of time spent alone. Results indicated that the level of neuroticism moderates the association between social context and positive affect, but this was not statistically reliable. Conclusion: Being alone or in company makes a difference to positive affect. This may explain the protective effect that social relationships have on health and well-being. Compared to earlier phases of life, the relationship between personality dispositions and indicators of social relationships may not be as strong in late life.