Abstract In June 1979, the Royal Commission on the National Health Service published its report. Chaired by Sir Alec Merrison, the Commission covered England, Scotland, Wales and Northern Ireland. In 1976, the Royal Commission published and broadcast calls, asking the public to put forward their views on the NHS. In response, they received around 2,460 written evidence submissions, held fifty-eight oral evidence sessions, and met with about 2,800 individuals. In soliciting evidence, the Commission called on people to comment on their experience of the health service, submit that experience as evidence, and contribute suggestions for the NHS’s improvement. These submissions of evidence, mostly in the form of letters written to Merrison, are rich and revealing sources. While NHS staff, trade unionists, and professional organizations were invited to contribute their perspectives, patients and other non-clinical members of the British public also penned letters. In this article, I use the evidence submitted by self-proclaimed ‘ordinary’ people to contribute to emerging discussions about post-war British citizenship, and its intimate or quotidian relationship to the welfare state. I use these submissions as evidence for popular anxieties in the 1970s, and to explore the various ways that British citizens experienced and engaged with the NHS; investigate how they felt about its services; and consider the affective and political function of complaint.