Adult symptomatic lumbar scoliosis is a difficult condition, and it is unclear whether operative or non-operative treatment is ideal. Cost-effectiveness is an important consideration for any intervention. The authors of this study used data from a prior multi-centre RCT to perform a cost-utility analysis with 5-year follow-up. At all time points, the operative group had more quality-adjusted life years gained, but this came at a higher cost. The overall incremental cost-effectiveness ratio was below the $50,000 threshold in years 4 and 5 of the study, but neither treatment was dominant. Thus, both treatments are acceptable in terms of cost and benefit from an economic perspective.