A pilot-randomised controlled trial (RCT) examined the effects of a brief mindfulness-based intervention (MBI) on persistent pain patients and assessed the feasibility of conducting a definitive RCT. A brief (15 min) mindfulness body-scan audio was compared with an active control administered in a clinic and then used independently over 1 month. Immediate effects of the intervention were assessed with brief measures of pain severity, distraction and distress. Assessments at baseline, 1 week and 1 month included pain severity and interference, mood, pain-catastrophizing, mindfulness, self-efficacy, quality of life and intervention acceptability. Of 220 referred patients, 147 were randomised and 71 completed all assessments. There were no significant immediate intervention effects. There were significant positive effects for ratings of intervention 'usefulness' at 1 week (p = 0.044), and pain self-efficacy at 1 month (p = 0.039) for the MBI group compared with control. Evidently, it is feasible to recruit persistent pain patients to a brief MBI study. Strategies are needed to maximise retention of participants.Trial registration Current controlled trials ISRCTN61538090. Registered 20 April 2015.