Cancer is most curable when it’s detected at its earliest stages. An analysis of nearly 273,000 patients showed that between 2013 and 2014 there was a 1% increase in the percentage of breast, lung, and colorectal cancers diagnosed at the earliest, most treatable stage. Following full implementation of the Affordable Care Act (ACA), this study is the first to explore changes in the proportion of cancers – those that can be detected through screening – diagnosed at stage I.