Information overload in online environments leads individuals to be more likely to rely on heuristic cues to make decisions about (mis)information sharing. Drawing on dual-process models of information processing, namely the heuristic–systematic model and the elaboration likelihood model, we conducted a meta-analysis of 31 individual studies to examine the combined effects of five major heuristic cues on misinformation sharing. The results revealed that the affective heuristic of anxiety exerted the strongest impact on misinformation sharing ( r = .343), followed by three cognitive heuristics: the self-confirmation heuristic ( r = .249), endorsement heuristic ( r = .125), and fact-checking heuristic ( r = -.115)—but not the authority heuristic. The endorsement misinformation receives, consistency between misinformation and individuals’ prior attitudes or beliefs, anxiety people feel, and absence of fact-checking labels all make people more likely to share misinformation. Moderation analyses also highlight the importance of considering contextual and cultural factors in future research.