In a randomized controlled trial, we studied low-income adults newly covered by a primary care program to determine whether a cash incentive could encourage them to make an initial visit to a primary care provider. Subjects were randomly assigned to one of four groups: three groups whose members received $10 to complete a baseline survey during an interview and who were randomized to incentives of $50, $25, or $0 to visit their assigned primary care provider within six months after enrolling in the study; and a nonincentivized control group not contacted by the research team. Subjects in the $50 and $25 incentive groups were more likely to see a primary care provider (77 percent and 74 percent, respectively), compared to subjects in the $0 incentive group (68 percent). The effects of the intervention were about twice as large when we compared the proportions of subjects in the $50 and $25 incentive groups who visited their providers and the proportion in the nonincentivized group (61 percent). Cash incentive programs may steer newly covered low-income patients toward primary care, which could result in improved health outcomes and lower costs.