How a health emergency is defined and presented through the news media matters for public understanding and health outcomes. Previous studies have endeavored to identify the patterns of news sourcing in crisis coverage, specifically the interplay between political sources and health expert sources, but yielded inconclusive results. This study analyses the types and roles of actors (those entities mentioned in a story) and sources cited in news coverage of COVID-19 by surveying social media posts published by 15 UK news outlets coverage across Facebook, Twitter, and Instagram between 1 January to December 31 2020. Overall, the findings show the prominence of political sources in UK news and that the most frequently named sources were representatives of the UK government. Moreover, when stories involved political actors, they were more likely to be given a voice as a source. This demonstrates how COVID-19 was a generalized crisis for the UK, which cascaded beyond health and into other economic, social, and cultural domains. The data show some variations in sourcing patterns between the different social media platforms. The analysis suggests that this may reflect the conventions of presenting news on each platform, with some tending toward the model of consensus by prioritizing political and government sources, and others contributing to a sphere of legitimate controversy by giving voice to a wider range of sources. This is distinctive and opens up the possibility for further research on how journalists adapt stories for social media and the consequences for public health communication.