Background: Despite evidence of sex-based divergences in the natural history of aortic stenosis (AS), there is limited data on the sex differences in the hemodynamic progression and long-term outcomes of early-stage AS. Methods: This is a retrospective longitudinal study of patients aged ≥ 60 years with mild to moderate native AS who were identified from a tertiary care referral center between 2008-2016 and followed until 2018. All patients had at minimum 2 echocardiograms. The primary outcomes of all-cause mortality and aortic valve replacement (AVR) were both assessed by time-to-event analyses with multivariable-adjusted Cox regression. The secondary outcome of AS progression was assessed by annualized changes in echocardiographic parameters in a 1:1 propensity-matched group of males and females. Results: Of 2,660 included patients followed over a median duration of 5.6 years, the mean age was 74 years and 1,128 (42%) were female. There was no difference in all-cause mortality between sexes, irrespective of age, baseline AS severity, and receipt of AVR. Relative to males, females had a lower risk of AVR (aHR=0.77, 95% CI [0.65-0.92]; p=0.004) irrespective of age, type of aortic valve and baseline severity of AS (Figure). This finding persisted on sensitivity analyses excluding patients with a history of coronary artery disease, prior coronary bypass surgery (CABG), and who underwent concomitant CABG and AVR. On 1:1 propensity-matched analysis, females had significantly slower annualized decrease in indexed aortic valve area (-0.039 vs. -0.021 cm 2 /m 2 /year, p=0.04) and slower increase in mean gradient (1.60 vs. 1.01 mmHg/year, p<0.001),and maximum transvalvular velocity (0.08 vs. 0.11 m/s/year; p=0.04). Conclusion: In patients with mild to moderate AS, females had slower hemodynamic progression of AS and lower incidence of AVR despite similar mortality between sexes. Our findings suggest the need for sex-specific evaluation and management of native AS.