OBJECTIVES: The Belgian community pharmacist-led PHARMACOP intervention provided educational inhalation training sessions and motivational interviewing regarding medication use in patients with Chronic Obstructive Pulmonary Disease (COPD). The program significantly improved medication adherence and inhalation techniques compared with usual care. This study aimed to evaluate its cost-effectiveness. METHODS: An economic analysis was performed from the Belgian healthcare payer’s perspective. A Markov model was constructed in which a cohort of 1,000 patients with COPD receiving the 3-month PHARMACOP-intervention or usual care, was followed. This cohort had a mean age of 70 years, 66% were male, 43% current smokers and patients had a mean Forced Expiratory Volume in 1 second of % predicted of 50. Three types of costs were calculated: intervention costs, medication costs and exacerbation costs. Outcome measures included the number of hospital-treated exacerbations, cost per prevented hospital-treated exacerbation and cost per Quality Adjusted Life-Year (QALY) gained. Follow-up was 1 year in the basecase analysis. Univariate-, probabilistic sensitivity- and scenario analyses (including long-term follow-up) were performed to assess uncertainty. RESULTS: In the basecase analysis, the average overall costs per patient for the PHARMACOP-intervention and usual care were €2,221 and €2,448, respectively within the 1-year time horizon. This reflects cost savings of €227 for the PHARMACOP-intervention. The PHARMACOP-intervention resulted in the prevention of 71 hospital-treated exacerbations (167 for PHARMACOP versus 238 for usual care), i.e. 0.07 (95%CI: 0.04-0.10) incremental hospital-treated exacerbations per patient. In addition, a small (<0.001 QALYs) increase in QALYs was observed. Results showed robust cost-savings in various sensitivity analyses. CONCLUSIONS: Optimization of current pharmacotherapy (e.g. close monitoring of inhalation technique and medication adherence) has been shown to be cost-saving and should be considered before adding new therapies.