Purpose Major depression is associated with high levels of absence and reduced productivity. Therefore the costs to society are high. The aim of this study was to evaluate the cost-utility of collaborative care for major depressive disorder (MDD) compared to care as usual in an occupational healthcare setting. A societal perspective was taken. Methods In this randomised controlled trial, 126 sick-listed workers with MDD were included (65 collaborative care, 61 care as usual). Baseline measurements and follow up measures (3, 6, 9 and 12 months) were assessed by questionnaire. We applied the Trimbos/iMTA questionnaire for costs associated with psychiatric illness, the SF-HQL and the EQ-5D respectively measuring the health care utilization, production losses and general health related quality of life. Results The average annual healthcare costs in the collaborative care group were <euro>3,874 (95 % CI <euro>2,778-<euro>5,718) compared to <euro>4,583 (95 % CI <euro>3,108-<euro>6,794) in the care as usual group. The average quality of life years (QALY's) gained were lower in the collaborative care group, 0.05 QALY. The majority of the ICERS (69 %) indicate that collaborative care is less costly but also less effective than care as usual. Including the productivity costs did not change this result. Conclusions The cost-utility analysis showed that collaborative care generated reduced costs and a reduction in effects compared to care as usual and was therefore not a cost-effective intervention.