The purpose of this European Heart Rhythm Association survey was to assess the current practice concerning the use of oral anticoagulation in patients with post-operative atrial fibrillation (pre-existing or new-onset). The survey highlights the considerable heterogeneity of the type of anticoagulation, with 25% of the centres never using the non-vitamin K antagonist oral anticoagulants (NOACs) in this setting, as well the timing of oral anticoagulation initiation, the use and dosing of low-molecular-weight heparins, and the duration of anticoagulation when sinus rhythm is restored. One-third of the centres stated that they perceived that the risk of major pericardial bleeding requiring pericardiocentesis was higher when NOACs were used compared with vitamin K antagonists. Overall, the responding centres estimated the incidence of major pericardial haemorrhage to be 2.4%. More data are needed to inform practice guidelines in this field.