In this article, we introduce and showcase how social media can be used to implement experiments in public administration research. To do so, we pre-registered a placebo-controlled field experiment and implemented it on the social media platform Facebook. The purpose of the experiment was to examine whether government funding to nonprofit organizations has an effect on charitable donations. Theories on the interaction between government funding and charitable donations stipulate that government funding of nonprofit organizations either decreases (crowding-out), or increases (crowding-in) private donations. To test these competing theoretical predictions, we used Facebook’s advertisement facilities and implemented an online field experiment among 296,121 Facebook users nested in 600 clusters. Through the process of cluster-randomization, groups of Facebook users were randomly assigned to different nonprofit donation solicitation ads, experimentally manipulating information cues of nonprofit funding. Contrary to theoretical predictions, we find that government funding does not seem to matter; providing information about government support to nonprofit organizations neither increases nor decreases people’s propensity to donate. We discuss the implications of our empirical application, as well as the merits of using social media to conduct experiments in public administration more generally. Finally, we outline a research agenda of how social media can be used to implement public administration experiments.