Surgical aortic valve replacement (SAVR) is associated with an increased mortality risk in elderly or high-risk patients. Transcatheter aortic valve implantation (TAVI) is an alternative to surgery in patients with symptomatic severe aortic stenosis who are inoperable or at high operative risk. The impact of diabetes mellitus (DM) on patients referred to TAVI merits further investigation. The aim of our study was to evaluate the clinical characteristics and the impact of DM status on the updated Valve Academic Research Consortium 2-defined outcomes of TAVI and to stratify patient outcomes according to their initial glycated hemoglobin (HbA1c) levels. We enrolled and stratified patients who underwent TAVI at our institution according to DM status. A total of 586 patients were enrolled: 348 (59%) without DM and 238 (41%) with DM. There were no significant differences in 30-day mortality patients with diabetes compared to patients without diabetes (3.3% vs 2.9%, p = 0.974). Insulin-treated DM was not associated with adverse outcome in comparison to orally treated DM. To delineate the prognostic power of HbA1C in these patients, the cohort was divided into 3 groups according to HbA1C levels (<5.7%, 5.7% to 6.49%, and ≥6.5%). Patients with HbA1C ≥6.5% were at increased risk for mortality during follow-up (hazard ratio 2.571, 95% confidence interval 1.077 to 6.136, p = 0.033) compared to patients with HbA1C <5.7%. In conclusion, unlike SAVR, DM is not associated with an increased mortality risk after TAVI, nor is it associated with increased complications rates. A more poorly controlled disease, as manifested by elevated HbA1c levels, may be associated with increased mortality during long-term follow-up.