This study aims at determining the temporal trends and the socioeconomic differences in treatment and mortality following a diagnosis of aortic stenosis. Methods and results: A total of 45,026 patients with a first-time diagnosis of aortic stenosis were identified in the Danish National Patient Registry in the period 2000-17. The risk of AVR within the first year after diagnosis decreased (OR = 1.84 in 2000-02 compared to 2015-16) and the risk was lower in the low-level educational group (OR = 0.85) and in the medium-level group (OR = 0.94) compared to high-level education. The risk of death after AVR within the first year decreased (OR = 2.25 in 2000-02 compared to 2015-16) and the risk was higher in the low-level educational group (OR = 1.32) and in the medium-level group (OR = 1.28) compared to highlevel education. The risk of death within the first year after diagnosis, for those patients who did not get an AVR during the follow-up, decreased (OR = 3.08 in 2000-02 compared to 2015-16) and the risk was higher in the low-level educational group (OR = 1.21) and in the medium-level group (OR = 1.10) compared to high-level education. Conclusion: Since 2000 there has been a decrease in both AVR treatment rate, mortality rate after AVR and mortality rate in patients not receiving AVR. For patients with lower-level education there is lower AVR treatment rate, higher mortality rate after AVR and higher mortality rate in patients not receiving AVR.