OBJECTIVES: The purpose of this study conducted in France was to describe the direct costs to society of COPD per severity grades using the “Echantillon Generaliste de Beneficiaires”(EGB). EGB is a database which contains all health care resources used by a random 1/97 permanent sample of the French population covered by the national healthcare insurance system. METHODS: Several algorithms were developed to identify patients with COPD and to distinguish patients between four severity grades (1-4) based on health care consumption. These algorithms were based on age, rate and history of hospitalizations, treatments and tests received by the individuals. Exacerbations as well as their severity were identified through both antibiotics/corticosteroids drugs prescribed and hospitalizations. Total health care costs were calculated and a case-control approach was then used to estimate the cost of COPD. Exacerbations costs were calculated through a linear regression analysis including age and gender. RESULTS: Based on the 10,715 COPD patients identified in the EGB, its prevalence was estimated to 4.2% of the population beyond 40 years. The mean annual overall direct health care cost in this population was estimated to be €9,382. Annual average costs were €7,628; 10,770, 14,979 and 20,747 for severity grade 1-4 (severity data-base defined) respectively. The yearly cost of COPD itself was 5,516€: 45.5% related to hospital care and 20.0% to pharmaceuticals  (6.0% to long-acting bronchodilators). The average exacerbation cost was €1,664 (SD: €86.6). The global economic burden of COPD in France was therefore estimated over €7 billions (4% of the national health care expense). CONCLUSIONS: Our study provides new solutions to estimate the burden of COPD in France using existing national databases. It confirms that COPD is associated with significant economic burden and the striking direct relationship between the cost of care and severity of the disease.