Patients with atrial fibrillation (AF) were excluded from the trials evaluating carotid artery stent placement (CAS) or carotid endarterectomy (CEA). We identified the prevalence of atrial fibrillation and how it might be associated with outcomes in patients with symptomatic internal carotid artery (ICA) stenosis. We analyzed the data from the National Inpatient Sample between 2016 and 2021 with stenosis of ICA who underwent CAS or CEA. We compared the end points of intra- and post-procedural cerebral infarction, hemorrhage, discharge home and death based on the presence or absence of AF. We also compared the outcomes in AF patients who had CAS with those who had CEA. Atrial fibrillation was present in 3,785 (18.3%) of 20,645 patients who underwent either CAS or CEA between 2016 and 2021, while 16,860 did not have atrial fibrillation. The proportion of patients who developed acute myocardial infarction, respiratory failure, acute kidney injury, or required blood transfusion was higher in patients with atrial fibrillation among both CAS- and CEA-treated patients. There was no difference in odds of post-procedural stroke and/or death in patients with atrial fibrillation (compared with those without atrial fibrillation) who were treated with CAS (odds ratio [OR] 0.99, 95% confidence interval [CI] 0.62-1.60, p = 0.98) and those treated with CEA (OR 1.09, 95% CI 0.69-1.73, p = 0.72 in the multivariate analysis after adjusting for potential confounders. The length of stay and hospitalization cost were significantly higher in patients with atrial fibrillation. There was no difference in post-procedural stroke and/or death (10.7% versus 8.7%, p = 0.41) and discharge home (32.4% versus 26.8%, p = 0.13) in patients with atrial fibrillation who underwent CEA compared to those who underwent CAS in propensity-matched analysis. One in five patients with symptomatic ICA stenosis who undergo CAS or CEA have AF. We did not identify higher risk of post-procedural stroke and/or death irrespective of the procedure, but resource utilization was higher in AF patients.