People struggling with chronic pain may benefit from different types of non-pharmacological interventions such as self-management courses. Self-management courses aim to increase participants' skills and knowledge in managing chronic conditions. Community health-care services in Norway have increasingly established Healthy Life Centres (HLCs) to offer easily accessible interventions to people in need of support to better handle a life with chronic illness. The aim of this trial is to investigate the expectations, effect and experience of an easily accessible, group-based self-management course delivered at a HLC for people with chronic pain. This is an open pragmatic two-armed randomised controlled trial with an embedded qualitative study. The intervention is a self-management course comprising education, discussions, exchange of experiences between the participants, and physical movement exercises. The control group is offered a drop-in outdoor physical activity. The intervention period is 6 weeks. The primary outcome is patient activation measured by the patient activation measure (PAM). The secondary outcomes include measures of self-efficacy, pain and quality of life. Data will be collected at baseline, and after 3, 6 and 12 months. Using a mixed linear model, the number needed in each arm to achieve a power of 80 % becomes 55. To allow for dropout, the aim is to include 120 participants. Analysis will be done using mixed linear models. In the embedded qualitative study, we will perform semi-structured face-to-face interviews with a sample from both trial arms before randomisation and after 3 and 12 months. The topics elaborated will be motivation for participation and experiences with the activity related to possible changes in managing and coping with chronic pain. There is need for more knowledge on interventions delivering self-care support in an easily accessible way that aim to reach those in need of this kind of health service. This trial will produce important knowledge on the effect and the experiences of participants in such an easily accessible self-management course delivered in Norwegian public primary care. ClinicalTrials.gov: NCT02531282 . Registered on 21 August 2015.