Background Race and sex disparities in catheter ablation (CA) utilization for atrial fibrillation (AF) have been documented. Less is known about race and sex differences in comorbidity burden and quality of care outcomes after CA. Objectives We sought to characterize race and sex differences in patient and procedural characteristics and their impact on prolonged length of stay (LOS) after CA for AF. Methods A retrospective cohort of patients that received CA for AF between 2018-2024 was developed from our single center NCDR registry. The analysis was restricted to Non-Hispanic White (NHW) and Non-Hispanic Black (NHB) patients due to small sample sizes for other groups. The association between race, sex, and prolonged LOS was evaluated using a multivariate stepwise regression model. A sensitivity analysis was performed with the composite outcome of complications given its sparsity. Causal mediation analysis was performed to assess whether race differences in prolonged LOS were mediated by complications. Results Between 2018-2024, 3,345 patients were included in the cohort. NHB patients were younger and more likely to have Medicaid insurance, higher BMI, higher comorbidity burden, history of atrial flutter, prolonged LOS, and complications after ablation. They were less likely to have prior CA. Female patients were older, less likely to have private insurance and prior CA, and more likely to have paroxysmal AF, transient ischemic attack, and chronic lung disease. NHB race [aOR 1.90 (95% CI 1.24-2.88), p=0.003] and a composite outcome of procedural complications [aOR 156 (95% CI 72.5-377), p<0.001] were independently associated with prolonged LOS. The higher odds of prolonged LOS for NHB patients was not mediated by a higher level of complications in this group. Conclusion Prolonged LOS was more frequent among NHB patients undergoing CA. The higher odds of prolonged LOS among NHB patients was not mediated by a higher incidence of complications, suggesting that other factors like comorbidity burden and social determinants of health (SDOH) are more significant contributors. Policies focused on improving comorbidity management and addressing sociocultural disparities may reduce prolonged hospitalizations after CA for AF.