We studied the associations between psychosocial variables and sick-leave among patients with musculoskeletal pain. Patients (n = 586) seeking care to relieve their pain at health care and physiotherapy centres, completed a questionnaire about such variables as clinical characteristics (e.g. pain intensity), psychological well-being (e.g. burnout, depression) and coping strategies. The results show that the patients who had been on sick-leave for >30 days (n = 217), were significantly more often divorced, immigrants, blue-collar workers and less educated than the rest of the sample. Compared with the rest of the patients, they rated their pain as significantly more severe, frequent, complex and functionally impairing. They reported using more pain medication and tranquillizers, and having undergone more somatic treatments. These patients also showed higher scores on job strain, more symptoms of burnout, anxiety/depression and posttraumatic stress reactions, and poorer coping capacity. Logistic regression analyses revealed that an index related to perceived disability was a major predictor of sick-leave within the group. After controlling for possible confounders, multivariate regression analyses showed that the strongest predictors of the disability index were symptoms of burnout and posttraumatic stress reactions. The results confirm that emotional distress, coping style and perceived disability are associated with sick-leave, after controlling for pain parameters and sociodemographic variables. The high levels of emotional distress and the poor coping capacity reported by the patients with a long history of absence due to illness suggest that cognitive behavioural interventions ought to be integrated in the treatment of musculoskeletal pain.