Background <p>Obesity is associated with an increased risk of postoperative morbidity. We aimed to analyze the impact of BMI on surgical complications in patients undergoing thyroidectomy.</p> Methods <p>This retrospective study was conducted in a single academic center. A total of 484 patients with open total thyroidectomy were considered eligible. These patients were divided in the non-obese (BMI &lt; 30&#xa0;kg/m²) and obese (BMI ≥ 30&#xa0;kg/m²) groups. A 1:2 case matching based on demographic (age and gender) and clinical (benign/malignant disease) variables was performed to generate homogenous study groups. A comparative analysis was carried out to show the differences between the two groups in terms of the occurrence of surgery-related outcomes.</p> Results <p>After case matching, 193 non-obese and 98 obese patients were included in the final analysis. There was no statistically significant difference in the rate of primary outcomes in the non-obese and obese groups: hypoparathyroidism (transient: 29% versus 21.4%, <i>p</i> = 0.166; permanent: 11.4% versus 15.3%, <i>p</i> = 0.344, respectively) and recurrent laryngeal nerve palsy (transient: 13.9% versus 11.2%, <i>p</i> = 0.498; permanent: 3.1% versus 2.0%, <i>p</i> = 0.594, respectively). A BMI ≥ 30&#xa0;kg/m² was associated with a significantly longer operative time (<i>p</i> = 0.018), while other secondary outcomes were not significantly affected by BMI.</p> Conclusions <p>Despite prolonged operative times in obese patients, total thyroidectomy could be performed safely and without increased risk of surgery-related morbidity, regardless of BMI.</p> Clinical trial number <p>Not applicable.</p>