PurposeTo determine if Medicaid expansion is associated with increased volumes of lung cancer screenings. MethodsA quasi-experimental study was performed to compare the annual growth rates in lung cancer screenings between states that expanded Medicaid (n = 31) versus those that did not (n = 17). Using the American College of Radiology Lung Cancer Screening Registry, we calculated the average annual growth rate between 2016 and 2019 for both groups. Secondary analyses between these two groups also included calculations of the percentages of studies considered appropriate by USPSTF criteria. ResultsNo significant difference was identified in the average annual growth in lung cancer screenings between Medicaid expanding and non-expanding states (57.6%, 50.3%, P = 0.51). No difference was observed in the percentage of studies considered appropriate (Medicaid expanding = 89.6%, non-expanding = 90.2%, P = 0.72). At baseline, there were socioeconomic differences between both groups of states. Medicaid expanding states had a more urban population (76.5% versus 67.9%, P = 0.05) and higher average incomes ($56,947, $49,876, P < 0.05). ConclusionNo association is found between Medicaid expansion and increasing volumes of lung cancer screening exams. Although no data is available in the registry for screening exams before the implementation of Medicaid expansion (2014), most nationwide estimates of lung screening rates report a low baseline (<5%). Furthermore, despite being advantaged in other ways, such as with a more urban population or with higher incomes, the Medicaid expansion cohort does not demonstrate a higher growth rate. These findings suggest Medicaid expansion alone will not increase lung cancer screenings.