We study how regulatory fragmentation, the overlap of oversight across multiple regulatory agencies, affects product quality failures among U.S. firms from 1996 to 2023. Using a comprehensive hand-collected dataset of product recalls and a firm-level text-based measure of regulatory fragmentation, we show that firms facing more fragmented regulation are significantly more likely to experience product quality failures. The effect is economically meaningful: a one–standard deviation increase in fragmentation raises recall likelihood by about 15% relative to the unconditional recall rate. To address endogeneity, we exploit Trump’s 2016 election and ensuing deregulation as a shock to regulatory fragmentation and show that more exposed firms experience fewer product quality failures. Mechanism analyses indicate that fragmentation operates primarily through internal organizational channels, weakening quality culture and reducing innovation, rather than through external supply-chain adjustments. The effects are stronger for firms operating in more competitive markets, with broader operational scope, and facing greater policy uncertainty.