New-onset left bundle branch block (LBBB) can develop after transcatheter aortic valve replacement (TAVR) resulting in worse outcomes.Describe clinical and echocardiographic outcomes with new-onset LBBB after TAVR.We included consecutive patients who underwent transfemoral-TAVR with SAPIEN-3 (S3) valve between April 2015 and December 2018. Exclusion criteria included pre-existing LBBB, right BBB, left anterior hemiblock, left posterior hemiblock, wide QRS ≥ 120ms, prior permanent pacemaker (PPM), and nontransfemoral access.Among 612 patients, 11.4% developed new-onset LBBB upon discharge. The length of stay was longer with new-onset LBBB compared with no LBBB [3 (2-5) days versus 2 (1-3) days; p 0.001]. New-onset LBBB was associated with higher rates of 30-day PPM requirement (18.6% vs. 5.4%; p 0.001) and 1-year heart failure hospitalizations (10.7% vs. 4.4%; p = 0.033). There was no difference in 3-year mortality between both groups (30.9% vs. 30.6%; p = 0.829). Further, new-onset LBBB was associated with lower left ventricular ejection fraction (LVEF) at both 30 days (55.9 ± 11.4% vs. 59.3 ± 9%; p = 0.026) and 1 year (55 ± 12% vs. 60.1 ± 8.9%; p = 0.002). These changes were still present when we stratified patients according to baseline LVEF (≥50% or50%). New-onset LBBBs were associated with a higher 1-year LV end-diastolic volume index (51.4 ± 18.6 vs. 46.4 ± 15.1 ml/mNew-onset LBBB after S3 TAVR was associated with higher PPM requirement, worse LVEF, higher LV volumes, and increased heart failure hospitalizations, with no difference in mortality.