This article examines how citizens categorize political activities and investigates to what extent, and how, the modes of activities that citizens engage in relate to the activities they consider to be political. Our analyses, relying on an online survey organized by YouGov in 2014 among a representative sample of British citizens (N = 1859), indicate that citizens categorize political activities along party and non-party lines. While a broad consensus exists about the extent to which party activities can be categorized as being political, this is less the case for non-party modes of participation. Furthermore, regression analyses reveal that citizens who participate in non-party activities are significantly more likely to consider both party activities and non-party activities to be political than those who do not engage in such activities. Those engaging in party-related activities are also slightly more likely to consider non-party activities to be political than those not participating in party activities.