In social vespid wasps, colony activity varies at many temporal scales. We studied the peak season activity (number of individuals entering the nest per min) of colonies of the social vespine wasp Dolichovespula saxonica in its native range in boreal Finland. Six colonies were monitored non-stop for a full day, starting before sunrise and ending after sunset. Shorter monitoring was carried out before and/or after the full-day monitoring. All colonies were active before sunrise and after sunset, and the overall activity was positively linked with colony size. Activity showed irregular minute-to-minute cycles in all colonies. The broader within-day dynamics were idiosyncratic among the colonies: activity varied generally between 40–100% of the peak, there were usually a few peaks per day, and the timing of the peaks varied. Ambient temperature was not related to activity dynamics consistently. Our study provides high-resolution information about the all-day activity of D. saxonica and underscores high among-colony variability in the dynamics of vespine wasps.