Background: In atrial fibrillation patients undergoing left atrial appendage occlusion with a Watchman device, surveillance imaging with a transesophageal echocardiogram (TEE) is typically performed at 45 days and 1 year to evaluate for device-related thrombus (DRT) and peri-device leak (PDL) before cessation of oral anticoagulation. The incidence of these complications is relatively low, and the ideal timing and duration of surveillance is unknown. We sought to evaluate the incidence of DRT and PDL after Watchman placement at 45 days and 1 year to determine the necessity of surveillance TEEs. Methods: We retrospectively analyzed 361 patients who received a Watchman device between January 2016 and January 2020. Baseline clinical and echocardiographic data, post-procedure antithrombotic therapy and surveillance echocardiographic data were collected from the NCDR LAAO Registry. Nested backward variable elimination regression was performed to derive independent predictors of the composite outcome of DRT and PDL. Results: A total of 286 patients who had post-procedure TEEs were included in the analysis. At 45 days, 9 patients had DRT (3.2%) and 44 patients had PDL (15.0%). At 1 year, 5 patients had DRT (5.6%) and 8 patients had PDL (8.9%). All DRT at 45 days was treated with continued anticoagulation while no change in protocol occurred with PDL. All DRT at 1 year occurred in new patients without prior thrombus. A history of prior transient ischemic attack (TIA) and thromboembolism were significantly associated with DRT or PDL at 1 year. Conclusions: We identified several patients with device-related complications at 45 days and 1 year despite appropriate device sizing and adequate use of antithrombotic therapy. The incidence of DRT increased from 45 days to 1 year and occurred in patients without prior thrombus. These findings highlight the importance of surveillance imaging and suggest the potential need for extended surveillance in select patients.