Aims. The aims of this study were to investigate whether 1) multispecialist tertiary intervention for complex spinal pain lead to reductions in spine-related healthcare costs and 2) baseline characteristics are related to health care consuming costs. Patients and methods. A cost study in a natural prospective cohort was carried out to investigate healthcare data of patients admitted to the Groningen Spine Center (GSC) ranging from two years prior to referral until two year after discharge. GSC intervention consisted of a multi-professional and -specialist based diagnosis and treatment. Patients (18 and 80 years) were included, suffering from specific as well as multifactorial spinal pain. Clinical data was merged with Health Care Insurance data and included questionnaires on demographics, work, pain, disability, quality of life and psychosocial functioning. Univariable (paired sample t-tests) and multivariable analyses (pooled OLS Regression and fixed effects models) were carried out. Results. Included were 997 patients (mean age 52 years) filing a total of 700.533 health care declarations. The findings suggest that the intervention had a significant negative effect on spine-related healthcare costs (predominantly on medical specialist and allied care). Reduction in healthcare costs after treatment was predicted by lower age, lower duration, lower BMI, high education, high job satisfaction, low physical workload, high mental health, better coping, lower pain intensity, high EQ-5D score and low financial worries at baseline (all p<0.01). Conclusion. This observational study showed that spine-related healthcare consuming can be effectively reduced after tertiary multi-specialist intervention for patients with complex spinal pain. The results are robust when controlling for background characteristics and are unlikely to be driven by regression to the mean. No conflicts of interest. No funding obtained