Dimitrov et al. argue that nonregimes are a worthy object of research attention that can contribute to international regime theory. Case studies, however, are still sparse. In this article, I examine Arctic haze, an issue area where a transnational environmental problem existed but no regime formed. Arctic haze was (re‐)discovered in 1971 but by 2000, the window of opportunity to form a regime had closed. What factors explain why an Arctic haze regime was not formed between 1971 and 2000? I claim science‐based factors play the dominant role. An analytical approach applicable to the science‐policy interface was employed. Using this approach, I conclude that the Arctic haze nonregime is best explained by the absence of scientifically documented and compelling transboundary consequences to ecosystems and humans. This is a product of the unique nature of the Arctic atmosphere.