BACKGROUND: Evaluations of complex interventions compared to usual care provided in palliative care are increasing. Not describing usual care may affect the interpretation of an intervention's effectiveness, yet how it can be described remains unclear. AIM: To demonstrate the feasibility of using multi-methods to describe usual care provided in randomised controlled trials (RCTs) of complex interventions, shown within a feasibility cluster RCT. DESIGN: Multi-method approach comprising usual care questionnaires, baseline case note review and focus groups with ward staff completed at study end. Thematic analysis of qualitative data, descriptive statistics of quantitative data, followed by methodological triangulation to appraise approach in relation to study aim. SETTING/PARTICIPANTS: Four general medical wards chosen from UK hospitals. Purposive sampling of healthcare professionals for usual care questionnaires, and focus groups. Review of 20 patients' notes from each ward who died during admission or within 100 days of discharge. RESULTS: Twenty-three usual care questionnaires at baseline, two focus groups comprising 20 healthcare professionals and 80 case note reviews. Triangulation of findings resulted in understanding the usual care provided to the targeted population in terms of context, structures, processes and outcomes for patients, families and healthcare professionals. Usual care was described, highlighting (1) similarities and embedded practices, (2) heterogeneity and (3) subtle changes in care during the trial within and across sites. CONCLUSIONS: We provide a feasible approach to defining usual care that can be practically adopted in different settings. Understanding usual care enhances the reliability of tested complex interventions, and informs research and policy priorities.