Aims Atrial fibrillation (AF) is associated with numerous cardiovascular complications. We sought to estimate the annual burden of cardiovascular complications in AF patients in French hospitals. Methods and results All AF patients hospitalized in France in 2012 were identified from the national public/private hospital database. Comorbid conditions and medical histories were documented using medical records dating back 5 years. Reasons for hospitalization, type of admission (emergency or otherwise), length of stay, rehabilitation transfers, and death at discharge were identified and costs of acute and rehabilitation care determined (2012 Euros). In total, 533 044 AF patients (mean age ± SD 78.0 ± 11.4 years, 47.1% women) were hospitalized in 2012 for any reason. Hospitalizations were cardiovascular-related in 267 681 patients [22.5% cardiac dysrhythmia, 18.3% heart failure, 7.1% vascular/ischaemic diseases, 6.9% stroke/transient ischaemic attack (TIA)/systemic embolism (SE), and 1.3% haemorrhages]. Patients with stroke/TIA/SE had higher rates of emergency admission (68.1%), transfer to rehabilitation unit (28.1%), and death at discharge (13.7%) than those with other cardiovascular complications, with the exception of haemorrhages, where emergency admission rates were similar. They also had longer mean lengths of stay (12.6 ± 13.2 days for acute care and 46.8 ± 42.5 days for rehabilitation). The annual total cost (acute care and rehabilitation) for all hospitalized cardiovascular events was €1.94 billion, of which heart failure represented €805 million, vascular/ischaemic diseases €386 million, stroke €362 million, cardiac dysrhythmia €341 million, and haemorrhage €48 million. Conclusion Half a million patients with AF were hospitalized in France in 2012. Cardiovascular-related hospitalizations involved half of these admissions, for a global burden of almost €2 billion, equivalent to 2.6% of total expenditure in French hospitals. Among these hospitalizations stroke/TIA/SE represented costly, but potentially preventable, complications.