On 16 th February 2016, the launch of the Sentinel-3A satellite marked the first step towards a new era of operational Delay-Doppler altimetry over ice sheets. Given the provision of these novel altimeters for decades to come, and the long-term benefits they can offer to a range of glaciological applications, it is important to establish their capacity to monitor ice sheet elevation and elevation change. Here, we present the first analysis of Sentinel-3 Delay-Doppler altimetry over the Antarctic Ice Sheet, and assess the accuracy and precision of retrievals of ice sheet elevation across a range of topographic regimes. Over the ice sheet interior, we find that the instrument achieves both an accuracy and a precision of the order of 10 cm, with ~ 98 % of the data validated being within 50 cm of co-located airborne measurements. Across coastal regions, which exhibit steeper and more complex topography, the accuracy decreases slightly, although ~ 60–85 % of validated data are still within 1 meter of co-located airborne elevation measurements. Finally, we explore the utility of the instrument for mapping elevation change, and show that, with less than 2 years of available data, it is possible to resolve known signals of ice dynamic imbalance. Our analysis demonstrates a new, long-term source of measurements of ice sheet elevation and elevation change, and the early potential of this novel operational system for monitoring ice sheet imbalance for decades to come.