The dynamics of feeding and other behavioural activities of pigs in large social groups are not well understood. Therefore, the objective of this study was to gain a better understanding of feeding and other behavioural activities and the impacts of larger social groups on social stress in grower finisher pigs. One main concern of large group sizes for pigs is the potential for increased social stressors. Results from this experiment do not support this concern as no short or long-term responses of social stress were observed. Overall it was found that feeding behaviour was disturbed immediately following regrouping into large group sizes. Larger groups also seemed to take additional time to adapt feeding behaviours. Other behaviours such as eating/drinking, standing/walking and resting as well as diurnal patterns of these activities were not affected by large group housing. It is suggested that management of feeding behaviour in terms of accessing feeders may be critical immediately following formation of pigs into larger groups.