Recent political trends in many countries have sparked renewed interest in populism. Despite general agreement that the affective/emotive aspects of political communication are particularly important in this, there is little recent analysis of how populists operationalise emotion or how they genuinely differ from mainstream parties in this sense. This article applies mixed methods to explore the 'affective-discursive practices' that characterise the discourses of two opposition parties in the United Kingdom: United Kingdom Independence Party (UKIP) and Labour. Comparison of the frequency of semantic subcategories related to emotion in corpora of press releases published by these parties on their websites is complemented by qualitative analysis of how specific emotional areas such as fear, anger and anxiety are invoked by the two parties. Different 'affective-discursive practices' underpin their discourses, since Labour characteristically frames reactions to social phenomena in terms of worry and concern, while UKIP legitimates fear and anger, but also projects more positive emotions.