Introduction Understanding primary care practices’ ‘readiness’ to engage in trials and their experience is important to inform trial procedures and supports. Few studies report on the feasibility of study procedures though this is a central part of pilot trials. We explored the acceptability and feasibility of study procedures of a cluster randomised pilot trial of an intervention in primary care to improve uptake of Ireland’s national diabetic retinopathy programme. Methods As part of the embedded mixed-methods process evaluation, quantitative and qualitative data were gathered across four general practices participating in the intervention. Interviews were conducted with a purposive sample of staff. Research logs on time spent on intervention delivery, staff assignment, resources, problems/changes, and reasons for drop-outs, were maintained over the course of intervention rollout, and practice audit data were analysed. Quantitative outcomes included recruitment, retention, completion, and data quality and completeness. Qualitative data on perceptions and experience of the pilot trial procedures were analysed using the Framework Method. Findings Nine staff (3 GPs, 4 nurses, 2 administrators) were interviewed. An interest in the topic area or in research motivated practices to take part in the trial. Reimbursement meant they could ‘afford’ to participate. Staff valued the researcher briefing at the start of the trial, to avoid ‘going in slightly blind’. While staff varied in audit skills and confidence, and some found this aspect of data collection challenging, a ‘step-by-step’ audit manual and regular researcher contact, helped them stay on track and troubleshoot during data collection. Audit quality was acceptable overall, however there were some issues, incorrect assignment of patient status being most common. Conclusion The IDEAs trial procedures were acceptable and feasible for primary care staff, however, challenges with conducting the audit may reflect staff skills gaps and the need for greater guidance and support from researchers.