ObjectiveTo determine the effectiveness of a person-centred intervention, including advice on physical activity, for improving pain intensity, physical activity, and other health-related outcomes in persons with chronic widespread pain, when delivered with digital eHealth support compared with standard telephone follow-up.DesignRandomized controlled trial.SubjectsIndividuals with chronic widespread pain (n = 139), aged 20–65 years, who had previously participated in a pain educational programme at primary healthcare units, were contacted during the period 2018–19 and randomized to an intervention group (n = 69) or an active control group (n = 70).MethodsTogether with a physiotherapist, participants in both groups developed person-centred health plans for physical activity. The intervention group was supported via a digital platform for 6 months. The active control group received support via one follow-up phone call. Primary outcome was pain intensity. Secondary outcomes were physical activity and other health-related outcomes.ResultsNo significant differences were found between the groups after 6 months, except for a significant decrease in global fatigue in the active control group compared with the intervention group.ConclusionFuture development of interventions supporting persons with chronic pain to maintain regular exercise is warranted.LAY ABSTRACTDespite documented positive effects of physical activity in treating persons with chronic widespread pain, it is challenging for many individuals with chronic widespread pain to independently continue to be physically active over time. This study measured the effects of a person-centred health plan to promote physical activity, delivered using eHealth support compared with standard follow-up by telephone, in persons with chronic widespread pain. Participants with chronic widespread pain (n = 139) were randomized into 2 groups: an intervention group, in which participants created an individual health plan together with a physiotherapist and were provided with digital eHealth support for 6 months; and an active control group, who also created an individual health plan together with a physiotherapist, and received one follow-up support phone call. The results showed no significant difference between the groups regarding change in the primary outcome, pain intensity. The active control group showed a significant decrease in global fatigue compared with the intervention group. Future development of interventions supporting persons with chronic pain to maintain regular exercise is warranted.