Lung cancer screening programs with computed tomography of the chest reduce mortality by more than 20%. Yet, they have not been implemented widely because of logistic and cost implications. Here, we sought to: (1) use real-life data to compare the outcomes and cost of lung cancer patients with treated medically or surgically in our region and (2) from this data, estimate the cost-benefit ratio of a lung cancer screening program (CRIBAR) soon to be deployed in our region (Catalunya, Spain). We accessed the Catalan Health Surveillance System (CHSS) and analysed data of all patients with a first diagnosis of lung cancer between 1 January 2014 and 31 December 2016. Analysis was carried forward until 30 months (t = 30) after lung cancer diagnosis. Main results showed that: (1) surgically treated lung cancer patients have better survival and return earlier to regular home activities, use less healthcare related resources and cost less tax-payer money and (2) depending on incidence of lung cancer identified and treated in the program (1-2%), the return on investment for CRIBAR is expected to break even at 3-6 years, respectively, after its launch. Surgical treatment of lung cancer is cheaper and offers better outcomes. CRIBAR is estimated to be cost-effective soon after launch.